System for safety syringes

Abstract

We provide a system for continuously injecting liquids. [Solution] The system includes a syringe body defining a proximal opening and a distal needle interface; a proximal stopper member and a distal stopper member forming a proximal and distal chamber; a first liquid in the distal chamber and a second liquid in the proximal chamber; a plunger configured to be manually operated to insert the proximal stopper member distally; and a needle hub assembly coupled to the syringe body, the needle assembly including a needle. The needle has an internal structure and defines a distal opening, an intermediate opening, and a proximal opening, which are fluid-coupled through the internal structure of the needle. By operating the plunger member to insert the proximal stopper member, the first liquid is first discharged from the distal chamber, and then, continuously, the second liquid is discharged from the proximal chamber.

Description

Technical Field

[0001] The present invention generally relates to injection systems, devices, and processes for facilitating various levels of control over fluid injection, and more particularly to systems and methods related to serial injection in a healthcare environment.

Background Art

[0002] Millions of syringes, such as those shown in (2) of FIG. 1A, are consumed daily in a healthcare environment. A typical syringe (2) includes a tubular body (4), a plunger (6), and an injection needle (8). As shown in FIG. 1B, such a syringe (2) can be used not only to inject fluid into a patient, but also to draw fluid from or discharge fluid into a container (10), such as a vial, ampule, bag, or other drug containment system. In fact, due to regulatory constraints and concerns about maintaining sterility in some countries, such as the United States, using a vial (10) with a syringe (2) as shown in a particular patient's environment results in such a vial being usable by only one patient and then having to be discarded, generating significant medical waste from the vial and the remaining discarded drug, and further contributing to the periodic shortage of certain critical drugs.

[0003] Referring to Figure 2A, three Luer syringes (12) are shown, each having a distally positioned Luer fitting shape (14) so ​​that they can be coupled with other devices having similar mating shapes, such as the Luer manifold assembly (16) shown in Figure 2B. The Luer manifold assembly in Figure 2B can be used to intravenously administer a liquid to a patient with or without the use of an intravenous injection bag. The Luer fitting (14) of the syringe in Figure 2A may be referred to as a “male” Luer fitting, and the one in Figure 2B (18) may be referred to as a “female” Luer fitting, and one of their Luer interfaces may be threaded so that the two sides can be coupled by relative rotation which can be combined with a compressive load (in which case the configuration may be referred to as a “Luer lock” configuration). In other words, in one Luer lock embodiment, rotation, sometimes combined with compression, can be used to engage threads in a male fitting (14) configured to engage with a flange on a female fitting (18), thereby bringing the devices together to form a fluid tight coupling. In another embodiment, a tapered interface shape can be used to provide a Luer engagement using compression without using threads or rotation (such configurations may be referred to as “slip-on” or “conical” Luer configurations). While such Luer couplings are considered relatively safe for the operator, there is a risk of chemical spills / leaks and component breakage during assembly of the Luer coupling.

[0004] On the other hand, using a needle injection configuration carries the risk of the sharp needle coming into contact with or piercing an undesirable person or structure. For this reason, so-called "safety syringes" have been developed. One embodiment of a safety syringe (20) is shown in Figure 3, in which a tubular shielding member (22) is spring-biased to cover the needle (8) when released from the locked position relative to the syringe body (4). Another embodiment of a safety syringe (24) is shown in Figures 4A-4B. In such a configuration, after the plunger (6) is fully inserted into the syringe body (4), the retractable needle (26) is retracted backward into a safe position within the tubular body (4) (28, 26), as shown in Figure 4B. Such configurations, which are themselves configured to contract, may be associated with issues of blood splatter / aerosolization, the unsafe storage of preload energy which may malfunction and act before the desired time, loss of accuracy when delivering total volume injection due to residual dead space in the spring compression volume, and / or loss of retraction rate control which may be associated with pain and patient anxiety.

[0005] The increasing demand for pre-filled syringe assemblies, such as those shown in Figures 5A and 5B, is further complicating the syringe market. Pre-filled syringe assemblies generally comprise a syringe body or "drug enclosure containing and delivering system" (34), a plunger tip, plug, or stopper (36), and a distal seal or cap (35) that can be fitted onto a Luer interface (Figure 5A shows a cap 35 in place, and in Figure 5B the cap has been removed to illustrate the Luer interface 14). The drug solution may be present in the volume between the distal seal and the distal end (37) of the plunger tip (36) or in a drug reservoir (40). The plunger tip (36) may include a standard butyl rubber material and may be coated with a biocompatible lubricating coating (e.g., polytetrafluoroethylene ("PTFE")) to facilitate a preferred seal and relative motion characteristics with respect to the associated syringe body structure and material. The proximal end of the syringe body (34) in Figure 5B includes a conventional integrated syringe flange (38) integrally formed with the material of the syringe body (34). The flange (38) is configured to extend radially from the syringe body (34) and may be configured to surround the syringe body (34) in full or partial circumference. A partial flange is known as a "clip flange," while, The other is known as a “full flange.” The flange is used to provide support for gripping the syringe with the fingers and pushing the plunger to perform an injection. The syringe body (34) preferably comprises a transparent material such as glass or polymer. The plunger tip (36) may be positioned within the syringe body (34) to form a volume within the chamber or reservoir (40) and to assist in the discharge of the associated fluid through the needle. The syringe body (34) may be defined as substantially cylindrical in shape (i.e., such that the plunger tip 36 having a circular cross-sectional shape can establish a seal with the syringe body (34)) or may be configured to have other cross-sectional shapes such as elliptical.

[0006] Such assemblies are desirable because they can be precisely volumetricated, standardized, and manufactured by a small number of manufacturers worldwide, who can afford to meet all of the world's ever-changing regulations regarding filling, packaging, and the selection of materials that come into contact with the drug / medicine, as well as the use of ingredients. However, such simple configurations generally fail to meet new global standards for single use, safety, auto-deactivation, and needle-stick prevention. Therefore, certain suppliers are moving towards more “vertical” solutions, such as those depicted in Figure 5C (41), which attempt to meet all or at least some of the above standards in a single solution, and as a result of attempting to meet these standards for many different scenarios, such products may have significant limitations (including some of those mentioned above with reference to Figures 3-4B) and relatively high inventory and utilization costs.

[0007] Furthermore, as the number of injectable liquids (e.g., drugs) increases, the requirement arises that two or more components are preferably injected sequentially (e.g., into the patient) within a short time (e.g., a few seconds) from one another. Multiple components can be injected sequentially using separate injection devices (e.g., pre-loaded syringes), or by sequentially drawing multiple components from separate open containers using the same injection device and injecting them sequentially. However, in this way, sequential injection using separate injection devices, or sequentially drawing and injecting multiple components, results in the needle being inserted into the patient multiple times, which can be inaccurate and lead to component loss. In addition, sequential injection using separate injection devices, or sequentially drawing multiple components into syringes, may unnecessarily expose the user to one or more uncapped needles. Moreover, sequential injection using separate injection devices, or sequentially drawing and injecting multiple components, may cause unacceptable delays between the injections of multiple components.

[0008] In some cases, chemical reactions may occur between the components of a multi-component injection. The use of conventional dual-chamber syringes, where components are mixed together inside the syringe, may not be suitable for these reactive components, as the mixed components may become unsuitable for injection. Some specific examples of this phenomenon include an increase in the viscosity of the combined drugs when the components are mixed together, resulting in difficulty in easily injecting the drugs through the needle. Other reactions, such as exothermic and endothermic reactions, may also occur, potentially interfering with the use of conventional dual-chamber injection systems.

[0009] Existing dual-chamber injection systems (see, for example, U.S. Patent No. 4,874,381) utilize an external bypass channel formed within the outer wall of the syringe body. The external bypass channel is positioned such that as the plunger moves distally, the distal stopper moves distally, exposing the external bypass channel to both the proximal and distal chambers, allowing the fluid to move from the proximal to the distal chamber around the distal stopper and mix with the drug components in the distal chamber. When the needle or syringe is capped for drug storage, these external bypass channel dual-chamber injection systems experience an increase in pressure in the distal chamber during transfer and mixing. This increase in pressure causes resistance to transfer, making it difficult to transfer all the fluid from the proximal to the distal chamber. Additionally, the increase in pressure increases the force that must be maintained on the plunger rod during mixing. To minimize the effects of increased pressure, external bypass dual-chamber injection systems require the syringe to be opened and the needle cap removed before the fluid is transferred and mixed, or after mixing has occurred, in order to allow the pressure in the distal chamber to dissipate during transfer and mixing. These requirements increase the risk of needle stick injury and / or require an additional step by the user. It is beneficial to incorporate a shielded and ventilated pre-installed needle with built-in needle retraction into the dual-chamber injection system. The shielded and ventilated needle shield invention disclosed herein is applicable to external bypass dual-chamber injection systems. Additionally, it is beneficial to incorporate a plunger position control methodology to maintain precise control of the distal stopper position during transfer and mixing.

[0010] In addition, as the number of injectable fluids (e.g., drugs) increases, another requirement arises: the time the injectable fluids are exposed to metal (e.g., the stainless steel of the needle) must be minimized. Yet another requirement is that the system should be suitable for patient self-injection.

[0011] It is also desirable to incorporate needle-stick prevention technology into the injection system. By being able to retract at least partially the tip of the needle into the inside of the syringe, the person administering the injection is protected, and the patient is protected from accidental needle-stick injuries.

[0012] An injection system is needed that addresses the shortcomings of currently available configurations. In particular, a multi-chamber safe injection solution is required that can utilize the existing, relatively well-controlled supply chain of conventionally delivered pre-filled syringe assemblies, such as those described with reference to Figures 5A and 5B.

[0013] By retracting the needle assembly, the distal end of the sharp needle moves inside the needle hub or injection system body / syringe body, preventing accidental needle stick injuries.

[0014] Some existing injection and / or needle retraction systems include a needle assembly having an opening that can be blocked if other parts of the needle assembly are crushed during assembly and / or use. Some existing injection and / or needle retraction systems include a needle assembly that can become structurally non-functional during assembly and / or use. Some existing injection and / or needle retraction systems include a needle assembly that may allow the injectable agent and / or components of the injectable agent to be inadvertently discharged from inside the injection system body to outside the injection system body through the distal opening of the injection system body.

[0015] Needle retraction systems and their components are needed to address the shortcomings of currently available configurations. In particular, needle assemblies are needed that have openings that resist occlusion when other parts of the needle assembly are crushed during assembly and / or use. Needle assemblies that resist structural failure during assembly and / or use are also needed. Needle assemblies that prevent accidental discharge of the injectable drug through the distal opening of the injection system body are further needed. By addressing these and other limitations of needle retraction systems, it will be possible to manufacture injection and / or needle retraction systems cost-effectively and easily. [Overview of the Initiative]

[0016] Some embodiments relate to injection systems. In particular, embodiments relate to multi-chamber continuous injection systems and multi-chamber safety injection systems that move needles to a protective configuration to minimize accidental user injury and contamination by used needles.

[0017] In one embodiment, a system for continuously injecting a liquid includes a syringe body defining a proximal opening and a distal needle interface at its distal end. The system also includes a proximal stopper member and a distal stopper member located within the syringe body, with a proximal chamber formed between the proximal and distal stopper members, and a distal chamber formed between the distal stopper member and the distal end of the syringe body. The system further includes a first liquid in the distal chamber and a second liquid in the proximal chamber. Furthermore, the system includes a plunger configured to be manually operated to insert the proximal stopper member distally relative to the syringe body. In addition, the system includes a needle hub assembly containing a needle, coupled to the distal needle interface of the syringe body. The needle defines a needle interior, a distal end opening, an intermediate opening, and a proximal opening. The distal end opening, intermediate opening, and proximal opening are fluid-coupled through the needle interior. By operating the plunger member to insert the proximal stopper member distally to the syringe body, first, a first liquid is dispensed from the distal chamber through the needle, and then, continuously, a second liquid is dispensed from the proximal chamber through the needle.

[0018] In one or more embodiments, the needle includes a tubular member and a solid proximal end feature connected thereto. The needle interior, distal end opening, intermediate opening, and proximal opening can be formed within the tubular member. The solid proximal end feature may be joined to the tubular member by welding. The welding may be a fillet weld configured to reduce the cutting of the proximal stopper member when the needle penetrates the proximal stopper member, compared to a needle without fillet welding. The weld may be tapered in the proximal direction. The proximal opening may be adjacent to the weld. The solid proximal end feature may be cold-formed. The distal end of the solid proximal end feature may be located within the proximal end of the tubular member. The distal end of the solid proximal end feature and the proximal end of the tubular member can define an annular lumen that fluidly connects the proximal opening to the needle interior, intermediate opening, and distal end opening.

[0019] In one or more embodiments, the proximal opening has a rounded edge configured to reduce the cutting of the proximal stopper member when the needle penetrates the proximal stopper member compared to a needle without a rounded edge. The proximal opening may be an elongated slot. The length of the elongated slot can provide a tolerance for variations related to the proximal stopper member and / or the distal stopper member. Variations related to the proximal stopper member and / or the distal stopper member may be selected from the group consisting of strain on the proximal surface of the distal stopper member, the position of the proximal stopper member relative to the elongated slot, and the position of the distal stopper member relative to the elongated slot. The length of the elongated slot may be about 1 / 32 inch to about 1 / 16 inch. The distance between the elongated slot and the solid proximal end can minimize backflow leakage of the first and second fluids to the plunger. The elongated slot may be formed using a grinding wheel. The first and second sizes of the distal and proximal chambers can be changed by moving the proximal and distal stopper members relative to the syringe body.

[0020] In one or more embodiments, the plunger member includes a needle retention feature located inside the plunger, an energy storage member located inside the plunger, and an energy storage member latch member located inside the plunger. The needle hub assembly may include a hub and a needle retaining member configured to connect the needle to the hub. The needle may be made at least partially retractable into the plunger when the plunger member is operated relative to the syringe body to convert the energy storage member latch member from a latched state to an unlatched state. The needle may be configured to fully puncture at least the distal stopper member so that it is at least partially retracted into the plunger. The energy storage member latch member may be configured to convert from a latched state to an unlatched state, after the second fluid has been discharged from the proximal chamber through the needle, thereby at least partially retracting the needle into the plunger. The needle retention feature may be configured to activate the conversion of the energy storage member latch member from a latched state to an unlatched state when the plunger member is operated to insert the proximal stopper member into the distal end of the syringe body.

[0021] In one or more embodiments, the distance between the proximal opening and the distal end of the syringe body is substantially equal to the length of the distal stopper member, and as a result, when the distal stopper member is inserted into the distal end of the syringe body, the proximal stopper member is inserted distally to the needle, and the proximal opening is positioned within the proximal chamber. The proximal stopper member, the distal stopper member and the syringe body can be configured such that distal forces applied to the proximal stopper member are transmitted to the distal stopper member through the second fluid until the proximal stopper member is inserted distally to the needle and the proximal opening is positioned within the proximal chamber.

[0022] In one or more embodiments, the system includes a first injection configuration in which the proximal opening is located within the distal chamber or within a distal stopper member, and a second injection configuration in which the proximal opening is located within the proximal chamber, thereby allowing a second liquid to be transferred from the proximal chamber through the proximal opening and the inside of the needle to exit through the distal end opening. The proximal stopper member and the distal stopper member may include a first polymer coating and a second polymer coating on their respective distal and proximal surfaces, respectively, so that the proximal chamber is defined by the syringe body and the first and second polymer coatings. The distal stopper member may have a funnel that tapers in the proximal direction and a space located at the tapered proximal end of the funnel. An intermediate opening may be adjacent to the distal end of the syringe body.

[0023] In another embodiment, a method for sequentially injecting a first liquid and a second liquid into a patient includes providing a system comprising a syringe body defining a proximal opening of the syringe and a distal needle interface at its distal end. The system also includes a proximal stopper member and a distal stopper member disposed within the syringe body, with a proximal chamber formed between the proximal and distal stopper members and a distal chamber formed between the distal stopper member and the distal end of the syringe body. The system further includes a first liquid in the distal chamber and a second liquid in the proximal chamber. Furthermore, the system includes a plunger configured to be manually operated to insert the proximal stopper member distally to the syringe body. In addition, the system includes a needle having a needle interior, a distal end opening, an intermediate opening, and a proximal opening, the distal end opening, the intermediate opening, and the proximal opening being fluid-coupled through the needle interior. The method also includes advancing the plunger member to discharge a first portion of the first liquid from the distal chamber through the needle interior and the distal end opening. The method also further includes advancing the plunger member to discharge a second liquid from the proximal chamber through the proximal opening, the inside of the needle, and the distal end opening. Furthermore, the method includes advancing the plunger member to discharge a second portion of the first liquid from the proximal chamber through the inside of the needle and the distal end opening.

[0024] In one or more embodiments, the method also includes automatically retracting the distal needle tip into the needle hub or syringe body when the second portion of the first liquid is discharged through the distal end opening. The method may also include fully puncturing at least the distal stopper member and at least partially retracting the needle into the plunger. The method may also include inserting the distal end of the needle into the patient before advancing the plunger member to discharge the first portion of the first liquid from the distal chamber, thereby positioning the distal end opening of the needle into the patient before the first portion of the first liquid is discharged. The method may also include removing air from the distal chamber before inserting the distal end of the needle into the patient. Removing air from the distal chamber may include holding the syringe body in a substantially vertical position and manipulating the plunger member to insert the proximal stopper member distally to the syringe body. By advancing the plunger member, the proximal stopper member can be inserted distally to the syringe body, thereby applying a distal force through the second liquid, inserting the distal stopper member distally to the syringe body, and causing the first portion of the first liquid to be discharged from the distal chamber through the inside of the needle and the distal end opening.

[0025] In one or more embodiments, the system includes a first injection configuration in which the proximal opening is located within the distal chamber or within the distal stopper member; a second injection configuration in which the proximal opening is located within the proximal chamber, thereby enabling the transfer of a second liquid from the proximal chamber through the proximal opening and the inside of the needle to exit through the distal end opening; and a third injection configuration in which the proximal stopper member and the distal stopper member are in contact with each other, and the proximal opening is closed by the proximal stopper member and / or the distal stopper member. The system may be in the first injection configuration when the plunger member is advanced so that a first portion of the first liquid is discharged from the distal chamber through the inside of the needle and the distal end opening. The system may be in the second injection configuration when the plunger member is further advanced so that the second liquid is discharged from the proximal chamber through the proximal opening, the inside of the needle and the distal end opening. The system can be in a third injection configuration when the plunger member is advanced and the second portion of the first liquid is discharged from the distal chamber through the inside of the needle and the distal end opening.

[0026] In one or more embodiments, the needle includes a tubular member and a solid proximal end feature portion coupled thereto, wherein the needle interior, distal end opening, intermediate opening, and proximal opening are formed within the tubular member. The solid proximal end feature portion may be joined to the tubular member by welding. The welding may be a fillet weld configured to reduce the cutting of the proximal stopper member when the needle penetrates the proximal stopper member compared to a needle without fillet welding. The distal end of the solid proximal end feature portion may be located within the proximal end of the tubular member. The distal end of the solid proximal end feature portion and the proximal end of the tubular member can define an annular lumen that fluidly couples the proximal opening to the needle interior, intermediate opening, and distal end opening.

[0027] In one or more embodiments, the proximal opening has a rounded edge configured to reduce cutting of the proximal stopper member when the needle passes through the proximal stopper member, as compared to a needle without a rounded edge. The proximal opening may be an elongated slot. The length of the elongated slot can provide a tolerance for variations related to the proximal stopper member and / or the distal stopper member. Variations related to the proximal stopper member and / or the distal stopper member can be selected from the group consisting of distortion of the proximal surface of the distal stopper member, the position of the proximal stopper member relative to the elongated slot, and the position of the distal stopper member relative to the elongated slot. The length of the elongated slot may be from about 1 / 32 inch to about 1 / 16 inch. The length of the elongated slot can minimize back leakage of the first liquid and the second liquid into the plunger.

[0028] In one or more embodiments, the distal stopper member has a funnel that tapers in the proximal direction and a space disposed at the tapered proximal end of the funnel. The method can also include guiding the needle into the space at the tapered proximal end of the funnel, thereby aligning the needle proximal end feature with the needle retention feature inside the plunger. The intermediate opening may be adjacent to the distal end of the syringe body.

[0029] In yet another embodiment, a system for continuously injecting a liquid includes a syringe body that defines a proximal opening of the syringe and a distal needle interface at its distal end. The system also includes a proximal stopper member, an intermediate stopper member, and a distal stopper member disposed within the syringe body, with a proximal chamber formed between the proximal stopper member and the intermediate stopper member, an intermediate chamber formed between the intermediate stopper member and the distal stopper member, and a distal chamber formed between the distal stopper member and the distal end of the syringe body. The system further includes a first liquid within the distal chamber, a second liquid within the intermediate chamber, and a third liquid within the proximal chamber. Additionally, the system includes a plunger configured to be manually operated to insert the proximal stopper member distally relative to the syringe body. In addition, the system includes a needle hub assembly coupled to the distal needle interface of the syringe body, and the needle assembly includes a needle. The needle can define a needle interior, a distal end opening, an intermediate opening, and a proximal opening. The distal end opening, the intermediate opening, and the proximal opening can be fluidly coupled through the needle interior. By operating the plunger member to insert the proximal stopper member distally relative to the syringe body, the first liquid, the second liquid, and the third liquid can be continuously ejected through the needle.

[0030] In one or more embodiments, by operating the plunger member to insert the proximal stopper member distally relative to the syringe body, the first liquid, the second liquid, and the third liquid are continuously ejected through the needle in the order of a first portion of the first liquid from the distal chamber, the second liquid from the intermediate chamber, a second portion of the first liquid from the distal chamber, and the third liquid from the proximal chamber.

[0031] In one or more embodiments, by operating a plunger member to insert a proximal stopper member distally to the syringe body, a first liquid, a second liquid, and a third liquid are continuously discharged through the needle in the order of the first liquid from the distal chamber, the second liquid from the intermediate chamber, and the third liquid from the proximal chamber. The needle may include a tubular member and a solid proximal end feature connected thereto, and the needle interior, distal end opening, intermediate opening, and proximal opening may be formed within the tubular member. The solid proximal end feature may be joined to the tubular member by welding. The welding may be a fillet weld configured to reduce the cutting of the proximal and intermediate stopper members when the needle penetrates them, compared to a needle without fillet welding. The weld may be tapered in the proximal direction. The solid proximal end feature may be cold-formed. The distal end of the solid proximal end feature may be located within the proximal end of the tubular member. The distal end of the solid proximal end feature and the proximal end of the tubular member can define an annular lumen that fluidly connects the proximal opening to the inside of the needle, the intermediate opening, and the distal end opening.

[0032] In one or more embodiments, the proximal opening has a rounded edge configured to reduce the risk of cutting the proximal and intermediate stopper members when the needle penetrates them, compared to a needle without a rounded edge. The proximal opening may be an elongated slot. The length of the elongated slot can provide tolerance for variations related to the proximal stopper member, the intermediate stopper member, and / or the distal stopper member. Variations related to the proximal and / or distal stopper members may be selected from the group consisting of strain on the proximal surface of the distal stopper member, strain on the proximal surface of the intermediate stopper member, the position of the proximal stopper member relative to the elongated slot, the position of the intermediate stopper member relative to the elongated slot, and the position of the distal stopper member relative to the elongated slot. The length of the elongated slot may be about 1 / 16 inch to about 1 / 8 inch. The distance between the elongated slot and the solid proximal end can minimize backflow leakage of the first, second, and third liquids into the plunger. The elongated slots may be formed using a grinding wheel.

[0033] In one or more embodiments, the first, second, and third sizes of the distal, intermediate, and proximal chambers can be changed by moving the proximal stopper member, intermediate stopper member, and distal stopper member relative to the syringe body. The plunger member may include a needle placement feature located inside the plunger, an energy storage member located inside the plunger, and an energy storage member latch member located inside the plunger. The needle hub assembly may include a hub and a needle holding member configured to connect the needle to the hub. The needle may be made at least partially retractable into the plunger when the plunger member is operated relative to the syringe body to convert the energy storage member latch member from a latched state to an unlatched state. The needle may be configured to fully puncture at least the distal stopper member and the intermediate stopper member so that it is at least partially retracted into the plunger. The energy storage member latch member may be configured to convert from a latched state to an unlatched state that at least partially retracts the needle into the plunger after the third fluid has been discharged from the proximal chamber through the needle. The needle placement feature can be configured such that when the plunger member is operated to insert the proximal stopper member into the distal end of the syringe body, it activates the conversion of the energy storage member latch member from a latched state to an unlatched state.

[0034] In one or more embodiments, the proximal stopper member, intermediate stopper member, distal stopper member, and syringe body can be configured such that, until the proximal stopper member is inserted distally to the needle and the proximal opening is positioned within the intermediate chamber, distal forces applied to the proximal stopper member are transmitted to the intermediate stopper member through a third liquid and to the distal stopper member through a second liquid. The system may have a first injection configuration in which the proximal opening is located within the distal chamber or within the distal stopper member; a second injection configuration in which the proximal opening is located within the intermediate chamber, thereby enabling the second liquid to be transferred from the intermediate chamber through the proximal opening and the inside of the needle to exit the distal end opening; and a third injection configuration in which the proximal opening is located within the proximal chamber, thereby enabling the third liquid to be transferred from the proximal chamber through the proximal opening and the inside of the needle to exit the distal end opening. The proximal stopper member and the intermediate stopper member may include a first polymer coating and a second polymer coating on their respective distal and proximal surfaces, respectively, so that the proximal chamber is defined by the syringe body and the first and second polymer coatings. The distal stopper member may have a funnel that tapers in the proximal direction and a space located at the tapered proximal end of the funnel. The intermediate opening may be adjacent to the distal end of the syringe body.

[0035] In yet another embodiment, a method for sequentially injecting a first liquid and a second liquid into a patient includes providing a system comprising a syringe body defining a proximal opening of the syringe and a distal needle interface at its distal end. The system also includes a proximal stopper member, an intermediate stopper member, and a distal stopper member disposed within the syringe body, with a proximal chamber formed between the proximal stopper member and the intermediate stopper member, an intermediate chamber formed between the intermediate stopper member and the distal stopper member, and a distal chamber formed between the distal stopper member and the distal end of the syringe body. The system further comprises a first liquid in the distal chamber, a second liquid in the intermediate chamber, and a third liquid in the proximal chamber. Furthermore, the system includes a plunger configured to be manually operated to insert the proximal stopper member distally relative to the syringe body. In addition, the system includes a needle having a needle interior, a distal end opening, an intermediate opening, and a proximal opening, the distal end opening, the intermediate opening, and the proximal opening being fluid-coupled through the needle interior. The method also includes advancing the plunger member to discharge a first portion of the first liquid from the distal chamber through the inside of the needle and the distal end opening. The method also further includes advancing the plunger member to discharge a second liquid from the intermediate chamber through the proximal opening, the inside of the needle and the distal end opening. Furthermore, the method includes advancing the plunger member further to discharge a second portion of the first liquid from the proximal chamber through the inside of the needle and the distal end opening. In addition, the method includes advancing the plunger member further to discharge a third liquid from the proximal chamber through the proximal opening, the inside of the needle and the distal end opening.

[0036] In one or more embodiments, the method also includes automatically retracting the distal needle tip into the needle hub or syringe body when the second portion of the first liquid is dispensed through the distal end opening.

[0037] In another embodiment, a method for sequentially injecting a first liquid and a second liquid into a patient includes providing a system comprising a syringe body defining a proximal opening of the syringe and a distal needle interface at its distal end. The system also comprises a proximal stopper member, an intermediate stopper member, and a distal stopper member disposed within the syringe body, with a proximal chamber formed between the proximal stopper member and the intermediate stopper member, an intermediate chamber formed between the intermediate stopper member and the distal stopper member, and a distal chamber formed between the distal stopper member and the distal end of the syringe body. The system further comprises a first liquid in the distal chamber and a second liquid in the intermediate chamber. Furthermore, the system comprises a third liquid in the proximal chamber. In addition, the system comprises a plunger configured to be manually operated to insert the proximal stopper member distally relative to the syringe body, and a needle having a needle interior, a distal opening, an intermediate opening, and a proximal opening, the distal opening, the intermediate opening, and the proximal opening being fluid-coupled through the needle interior. The method also includes advancing the plunger member to discharge a first liquid from the distal chamber through the inside of the needle and the distal end opening. The method further includes advancing the plunger member to discharge a second liquid from the intermediate chamber through the proximal opening, the inside of the needle and the distal end opening. Furthermore, the system includes advancing the plunger member to discharge a third liquid from the proximal chamber through the proximal opening, the inside of the needle and the distal end opening.

[0038] In one or more embodiments, the method also includes automatically retracting the distal needle tip into the needle hub or syringe body when the third liquid is dispensed through the distal end opening.

[0039] Some embodiments relate to injection systems. In particular, some embodiments relate to safety injection systems having a needle assembly with an internal channel that resists crushing and structural failure. Other embodiments relate to safety injection systems having a needle assembly with a distal valve for preventing accidental discharge of the injectable drug through a distal opening of the injection system body.

[0040] In one embodiment, the syringe assembly includes a syringe body having an internal syringe, a proximal end and a distal end, and a needle attachment interface located at the distal end. The assembly also includes a needle assembly having a proximal portion, an intermediate connector, and a distal portion. The assembly further includes a needle latch assembly configured to prevent the needle assembly from moving proximal in a closed state and to release the needle assembly to allow the needle assembly to move proximal in an open state. The proximal portion has a crescent or dumbbell-shaped cross-section. The needle assembly is configured to retract into the syringe body after injection using the syringe assembly.

[0041] In one or more embodiments, the proximal portion includes a plurality of lobes, two of which form an angle of about 90°. The proximal portion may include a section having a taper of about 12° to 15°. The proximal portion may include a diameter reduction section and a proximal tip having a distal projection facing the diameter reduction section of about 0.0075”. The distal portion may include a sharp distal end.

[0042] In one or more embodiments, the assembly includes a proximal stopper member and a distal stopper member. The proximal stopper member, the distal stopper member and the syringe body define the proximal chamber, and the distal stopper member and the syringe body define the distal chamber. The needle assembly may include a radially extending annular flange adjacent to the proximal end of the intermediate connector. The distal portion may include a radially enlarged portion defining a longitudinal tube having a squircle cross-sectional shape. The distal portion may include a radially smaller portion having a rounded triangular cross-sectional shape.

[0043] In one or more embodiments, the distal stopper member includes a stopper insert comprising a pair of tabs. The syringe assembly may be configured to transfer fluid from the proximal chamber to the distal chamber to mix with components in the distal chamber, and subsequently discharge the mixed fluid and components from the distal chamber. The syringe assembly may be configured to discharge fluid from the distal chamber and subsequently discharge fluid from the proximal chamber. The proximal portion may have two separate compartments, each having a crescent or dumbbell-shaped cross-section.

[0044] In another embodiment, the syringe assembly includes a syringe body having an internal syringe and a proximal and distal end, and a needle assembly including a flow regulator positioned adjacent to the distal end of the syringe body.

[0045] In one or more embodiments, the flow regulator includes a housing that defines a liquid port and a compliant pin. The flow regulator may include an elastic seal configured to form a fluid-tight seal between the housing and the distal end of the syringe body. The elastic seal may be configured to close the liquid port when low pressure is present in the internal chamber of the syringe body. The elastic seal may be configured to open the liquid port when high pressure is present in the internal chamber of the syringe body. The assembly may include a stopper member having a stopper insert. The stopper insert may have an internal shape complementary to the external shape of the flow regulator.

[0046] Some embodiments relate to injection systems. In particular, some embodiments relate to safety injection systems having needle assemblies with internal channels that resist crushing and structural failure. Some embodiments relate to multi-chamber continuous injection systems and multi-chamber safety injection systems that move needles into a protective configuration to minimize accidental user injury and contamination by used needles.

[0047] In one embodiment, a system for continuously injecting a liquid includes a syringe body defining a proximal opening and a distal needle interface at its distal end. The system also includes a proximal stopper member and a distal stopper member disposed within the syringe body, with a proximal chamber formed between the proximal and distal stopper members, and a distal chamber formed between the distal stopper member and the distal end of the syringe body. The system further includes a first liquid in the distal chamber and a second liquid in the proximal chamber. Furthermore, the system includes a plunger configured to be manually operated to insert the proximal stopper member distally to the syringe body. In addition, the system includes a needle assembly having a proximal portion, an intermediate connector, and a distal portion. The proximal portion has a crescent or dumbbell-shaped cross-section. By operating the plunger member to insert the proximal stopper member distally to the syringe body, the first liquid is first discharged from the distal chamber through the needle, and then, continuously, the second liquid is discharged from the proximal chamber through the needle.

[0048] In one or more embodiments, the distal portion includes a sharp distal end. The proximal portion and the intermediate connector may have substantially equal diameters. The proximal portion may include a solid proximal end feature, and the intermediate connector may include a tubular member. The solid proximal end feature may be cold-formed. The distal end of the solid proximal end feature may be located within the proximal end of the tubular member.

[0049] In one or more embodiments, the proximal portion defines a longitudinal channel on its surface. The length of the longitudinal channel may be substantially equal to the length of the distal stopper member, so that when the distal stopper member is inserted into the distal end of the syringe body, the proximal stopper member is inserted distally to the needle, and the proximal end of the longitudinal channel is positioned within the proximal chamber. The proximal stopper member, the distal stopper member, and the syringe body may be configured such that distal forces applied to the proximal stopper member are transmitted to the distal stopper member through the second fluid until the proximal stopper member is inserted distally to the needle and the proximal opening is positioned within the proximal chamber. The length of the longitudinal channel can provide tolerance for variations related to the proximal stopper member and / or the distal stopper member. The variations relating to the proximal stopper member and / or the distal stopper member may be selected from the group consisting of the strain on the proximal surface of the distal stopper member, the position of the proximal stopper member relative to the longitudinal channel, and the position of the distal stopper member relative to the longitudinal channel.

[0050] In one or more embodiments, the distance between the longitudinal channel and the solid proximal end minimizes backflow leakage of the first and second liquids to the plunger. The longitudinal channel may be formed by stamping or injection molding.

[0051] In one or more embodiments, the system includes a first injection configuration in which the proximal end of a longitudinal channel is located within a distal chamber or a distal stopper member, and a second injection configuration in which the proximal end of a longitudinal channel is located within a proximal chamber, thereby allowing a second liquid to be transferred from the proximal chamber through the longitudinal channel out of the distal end opening of the distal portion of the needle assembly. The first and second sizes of the respective distal and proximal chambers can be changed by moving the proximal and distal stopper members relative to the syringe body.

[0052] In one or more embodiments, the system also includes a needle hub assembly having a hub and a needle retaining member configured to removably couple a needle to the hub. The plunger member may include a needle retention feature located inside the plunger, an energy storage member located inside the plunger, and an energy storage member latch member located inside the plunger. The needle may be made at least partially retractable into the plunger when the plunger member is operated relative to the syringe body to convert the energy storage member latch member from a latched state to an unlatched state. The needle may be configured to fully puncture at least the distal stopper member so that it is at least partially retracted into the plunger. The energy storage member latch member may be configured to convert from a latched state to an unlatched state, which at least partially retracts the needle into the plunger after a second fluid has been discharged from the proximal chamber through the needle. The needle retention feature needle may be configured to activate the conversion of the energy storage member latch member from a latched state to an unlatched state when the plunger member is operated to insert the proximal stopper member into the distal end of the syringe body. The proximal stopper member and the distal stopper member may include a first polymer coating and a second polymer coating on their respective distal and proximal surfaces, respectively, so that the proximal chamber is defined by the syringe body and the first and second polymer coatings.

[0053] In another embodiment, a system for continuously injecting a liquid includes a syringe body defining a proximal opening and a distal needle interface at its distal end. The system also includes a proximal stopper member and a distal stopper member located within the syringe body, with a proximal chamber formed between the proximal and distal stopper members, and a distal chamber formed between the distal stopper member and the distal end of the syringe body. The system further includes a first liquid in the distal chamber and a second liquid in the proximal chamber. Furthermore, the system includes a plunger configured to be manually operated to insert the proximal stopper member distally relative to the syringe body. In addition, the system includes a fluid transfer assembly having a proximal portion and an intermediate connector. The proximal portion has a longitudinal channel formed on its surface. The intermediate connector has a distal anchor member. By operating the plunger member to insert the proximal stopper member distally to the syringe body, first, a first liquid is dispensed from the distal chamber through the needle, and then, continuously, a second liquid is dispensed from the proximal chamber through the needle.

[0054] In one or more embodiments, the proximal portion is a solid metal elongated body, and the intermediate connector is a polymer body having a recess configured to receive the distal end of the proximal portion. The fluid transfer assembly may be molded from polymer as a single piece. The fluid transfer assembly may be molded from metal as a single piece.

[0055] In one or more embodiments, the distal anchor member has a rectangular cross-sectional shape. The distal anchor member may include a slot having a biasing member located inside, the biasing member may be configured to apply a radially outward force against the inner wall of the distal needle interface. The distal anchor member may include a corrugated wire-like member configured to apply a radially outward force against the inner wall of the distal needle interface. The distal anchor member may include a pair of flexible arms configured to apply a radially outward force against the inner wall of the distal needle interface. The distal anchor member may include a rubber sleeve configured to increase friction between the distal anchor member and the inner wall of the distal needle interface. The distal anchor member may also include proximal and distal openings configured to bypass the rubber sleeve.

[0056] In yet another embodiment, a system for continuously injecting a liquid includes a syringe body defining a proximal opening and a distal needle interface at its distal end. The system also includes a proximal stopper member and a distal stopper member located within the syringe body, with a proximal chamber formed between the proximal and distal stopper members, and a distal chamber formed between the distal stopper member and the distal end of the syringe body. The system further includes a first liquid in the distal chamber and a second liquid in the proximal chamber. Furthermore, the system includes a plunger configured to be manually operated to insert the proximal stopper member distally to the syringe body. In addition, the system includes a fluid transfer assembly having a proximal portion and an intermediate connector. The intermediate connector has a distal anchor member. By operating the plunger member to insert the proximal stopper member distally to the syringe body, the first liquid is first discharged from the distal chamber through the needle, and then, continuously, the second liquid is discharged from the proximal chamber through the needle.

[0057] In one or more embodiments, the proximal portion is a polymer body having multiple arms defined as its distal ends, and the intermediate connector is a polymer body having an opening configured to receive the arms of the proximal portion. The multiple arms are tapered radially outward so that the proximal portion can be coupled to the intermediate connector. The multiple arms are tapered radially outward so that they can exert a radially outward force against the inner wall of the distal needle interface.

[0058] In one or more embodiments, the distal anchor member includes a slot having a biasing member located inside. The distal anchor member may define a pair of bumps within the slot. The biasing member may define a pair of notches configured to receive the pair of bumps. The biasing member may be configured to apply a radially outward force to the inner wall of the distal needle interface. The proximal portion may have a longitudinal channel formed on its surface.

[0059] In yet another embodiment, a system for continuously injecting a liquid includes a syringe body defining a proximal opening and a distal needle interface at its distal end. The system also includes a proximal stopper member and a distal stopper member located within the syringe body, with a proximal chamber formed between the proximal and distal stopper members, and a distal chamber formed between the distal stopper member and the distal end of the syringe body. The system further includes a powdered drug component in the distal chamber and a liquid drug component in the proximal chamber. Furthermore, the system includes a plunger configured to be manually operated to insert the proximal stopper member distally relative to the syringe body. In addition, the system includes a needle assembly having a proximal portion, an intermediate connector, and a distal portion. The system also includes a one-way valve partially located within the distal needle interface and configured to minimize the transfer of powdered drug components from the distal chamber into the needle assembly.

[0060] In one or more embodiments, by operating the plunger member to insert the proximal stopper member distally by a first distance relative to the syringe body, the liquid drug component is transferred from the proximal chamber to the distal chamber to form a mixed liquid drug with the powder drug component. By operating the plunger member to insert the proximal stopper member distally by a second distance relative to the syringe body, the mixed liquid drug can be discharged from the distal chamber and pass through a one-way valve and a needle assembly.

[0061] In one or more embodiments, the distal portion includes a sharp distal end. The system may also include a needle retraction system located within the plunger member and configured to retract the needle assembly at least partially into the plunger member after injection. The one-way valve may include a proximal valve portion and a distal valve portion, the proximal valve portion may include a sleeve extending distally from its center.

[0062] In one or more embodiments, the sleeve is configured to have a tight tolerance between the sleeve and the distal valve portion of the needle assembly through which powdered drug components pass, so as not to be able to pass between the sleeve and the distal valve portion of the needle assembly. The tight tolerance may allow liquid drugs to pass between the sleeve and the distal valve portion of the needle assembly under pressure. The sleeve may define a plurality of longitudinal channels on its surface.

[0063] In one or more embodiments, the proximal valve portion of a one-way valve defines an opening through which it passes, and when the liquid drug is under pressure in the distal chamber, a liquid flow path is formed between the proximal and distal valve portions of the one-way valve, along a longitudinal channel, through a needle assembly, and to the outside of the system, from the distal chamber through the opening. The proximal and distal valve portions of the one-way valve may be configured to have tight tolerances from each other so that powder drug components cannot pass between the proximal and distal valve portions of the one-way valve. Tight tolerances may allow the liquid drug to pass between the proximal and distal valve portions of the one-way valve under pressure. The proximal valve portion may be rigid, and the distal valve portion may be flexible. When the liquid drug is under pressure in the distal chamber, at least a portion of the distal valve portion may bend away from the proximal valve portion.

[0064] The aforementioned embodiments and other embodiments of the present invention are described in the following detailed description. [Brief explanation of the drawing]

[0065] The above-described and other embodiments of the embodiment will be further described in detail with reference to the accompanying drawings. In the drawings, the same elements in different figures are referred to by common reference numerals.

[0066] [Figure 1] Figures 1A and 1B show various configurations of conventional injection syringes. [Figure 2] Figures 2A and 2B show various configurations of conventional injection syringes. [Figure 3] Figure 3 shows various configurations of conventional injection syringes. [Figure 4] Figures 4A and 4B show various configurations of conventional injection syringes. [Figure 5] Figures 5A to 5C show various configurations of conventional injection syringes. [Figure 6]Figures 6A and 6B illustrate a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 7] Figure 7 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 8] Figures 8A and 8B illustrate a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 9] Figure 9 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 10] Figures 10A and 10B illustrate a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 11] Figure 11 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 12] Figure 12 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 13] Figures 13A and 13B illustrate a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 14] Figure 14 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 15] Figures 15A and 15B illustrate a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 16] Figure 16 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 17]Figures 17A and 17B illustrate a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 18] Figure 18 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 19] Figures 19A and 19B illustrate a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 20] Figure 20 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 21] Figures 21A and 21B illustrate a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 22] Figure 22 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 23] Figures 23A and 23B illustrate a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 24] Figure 24 shows a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 25] Figures 25A and 25B illustrate a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 26] Figure 26 shows a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 27] Figures 27A and 27B illustrate a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 28]Figure 28 shows a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 29] Figures 29A and 29B illustrate a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 30] Figure 30 shows a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 31] Figures 31A and 31B show a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 32] Figure 32 shows a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 33] Figures 33A and 33B show a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 34] Figure 34 shows a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 35] Figures 35A and 35B illustrate a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 36] Figure 36 shows a continuous injection method using a pre-filled triple-chamber continuous injection system according to several embodiments. [Figure 37] Figure 37 shows a multi-chamber injection system that includes a distal tubular member connected to the distal end of the syringe body by a connector / retainer according to several embodiments. [Figure 38] Figure 38 shows a multi-chamber injection system including a distal tubular member connected to the distal end of the syringe body by a connector / retainer according to several embodiments. [Figure 39]Figure 39 shows a multi-chamber injection system including a distal tubular member connected to the distal end of the syringe body by a connector / retainer according to several embodiments. [Figure 40] Figure 40 shows a multi-chamber injection system that includes a distal tubular member connected to the distal end of the syringe body by a connector / retainer according to several embodiments. [Figure 41] Figure 41 shows a multi-chamber injection system that includes a distal tubular member connected to the distal end of the syringe body by a connector / retainer according to several embodiments. [Figure 42] Figure 42 shows a multi-chamber injection system that includes a distal tubular member connected to the distal end of the syringe body by a connector / retainer according to several embodiments. [Figure 43] Figures 43A and 43B are perspective and side views of a safety injection system according to several embodiments. [Figure 44] Figure 44A is a perspective view of a needle hub assembly according to several embodiments. Figure 44B is a perspective view, exploded view, detailed longitudinal section view, and detailed perspective view of a needle assembly according to several embodiments. [Figure 45] Figures 45A and 45B are perspective views, exploded views, detailed longitudinal sections, and detailed perspective views of needle assemblies according to several embodiments. [Figure 46] Figure 46 shows perspective views, exploded views, detailed longitudinal sections, and detailed perspective views of needle assemblies according to several embodiments. [Figure 47] Figures 47A and 47B are perspective and side views of the proximal portion of a needle assembly according to several embodiments. [Figure 48] Figures 48A and 48B are perspective views, detailed perspective views, and axial cross-sectional views of the proximal portion of the needle assembly according to two embodiments. [Figure 49] Figures 49A and 49B are perspective views, detailed perspective views, and axial cross-sectional views of the proximal portion of the needle assembly according to two embodiments. [Figure 50] Figures 50A and 50B are perspective views, detailed perspective views, and axial cross-sectional views of the proximal portion of the needle assembly according to two embodiments. [Figure 51] Figure 51 is a schematic diagram of a logic pipe according to several embodiments. [Figure 52] Figures 52A and 52B are detailed perspective views of the proximal and intermediate connectors according to two embodiments. [Figure 53] Figure 53 shows a side view, detailed perspective view (front and rear), perspective view, axial view, and perspective view of the proximal portion of a needle assembly according to several embodiments, showing its proximal tip. [Figure 54] Figures 54A and 54B are a side view, detailed perspective view (front and rear), perspective view, axial view, and perspective view showing the proximal tip of the proximal portion of a needle assembly according to several embodiments. [Figure 55] Figure 55 shows a side view, detailed perspective view (front and rear), perspective view, axial view, and perspective view of the proximal portion of a needle assembly according to several embodiments, showing its proximal tip. [Figure 56] Figure 56 shows a side view, detailed perspective view (front and rear), perspective view, axial view, and perspective view of the proximal portion of a needle assembly according to several embodiments, showing its proximal tip. [Figure 57] Figure 57 shows a side view, detailed perspective view (front and rear), perspective view, axial view, and perspective view of the proximal portion of a needle assembly according to several embodiments, showing its proximal tip. [Figure 58] Figure 58 is a longitudinal cross-sectional view of various steps of injection and needle capture using a safety injection system according to several embodiments. [Figure 59] Figure 59 is a longitudinal cross-sectional view of various steps of injection and needle capture using a safety injection system according to several embodiments. [Figure 60] Figure 60 is a longitudinal cross-sectional view of various steps of injection and needle capture using a safety injection system according to several embodiments. [Figure 61]Figure 61 is a longitudinal cross-sectional view of various steps of injection and needle capture using a safety injection system according to several embodiments. [Figure 62] Figure 62 is a longitudinal cross-sectional view of various steps of injection and needle capture using a safety injection system according to several other embodiments. [Figure 63] Figure 63 is a longitudinal cross-sectional view of various steps of injection and needle capture using a safety injection system according to several other embodiments. [Figure 64] Figure 64 is a longitudinal cross-sectional view of various steps of injection and needle capture using a safety injection system according to several other embodiments. [Figure 65] Figure 65 is a longitudinal cross-sectional view of various steps of injection and needle capture using a safety injection system according to several other embodiments. [Figure 66] Figure 66 is a longitudinal cross-sectional view of various steps of injection and needle capture using a safety injection system according to several other embodiments. [Figure 67] Figures 67A and 67B show perspective and side views of a dual-chamber safety injection system according to several embodiments. [Figure 68] Figures 68A and 68B are perspective and exploded views of fluid transfer assemblies according to several embodiments. [Figure 69] Figures 69A and 69B are perspective and side views of the proximal portion of a fluid transfer assembly according to several embodiments. [Figure 70] Figure 70 shows perspective and side views of the proximal portion of a fluid transfer assembly according to several embodiments. [Figure 71] Figures 71A, 71C, and 71D are detailed perspective views of the proximal portion of a fluid transfer assembly according to several embodiments. Figure 71B is an axial view of the proximal portion of a fluid transfer assembly according to several embodiments. [Figure 72]Figures 72A and 72B are perspective, side, and axial cross-sectional views of distal connectors of fluid transfer assemblies according to several embodiments. [Figure 73] Figures 73A, 73B, and 73C are perspective, side, and axial cross-sectional views of distal connectors of fluid transfer assemblies according to several embodiments. [Figure 74] Figures 74A and 74B are detailed longitudinal and axial cross-sectional views of a distal connector for fluid transfer inserted into the distal end of a syringe body according to several embodiments. [Figure 75] Figures 75A and 75B are longitudinal cross-sectional views and exploded views of distal connectors of stopper members having stopper inserts according to several embodiments. [Figure 76] Figures 76A, 76B, and 76C are detailed perspective views of a stopper member having a stopper insert according to several embodiments. [Figure 77] Figure 77 is a schematic diagram of various steps of fluid transfer and injection using a dual-chamber injection system according to several embodiments. [Figure 78] Figures 78A and 78B show perspective and side views of a dual-chamber safe continuous injection system according to several embodiments. [Figure 79] Figure 79 is a detailed longitudinal cross-sectional view of a dual-chamber safety continuous injection system according to several embodiments. [Figure 80] Figure 80 is a schematic diagram of various steps of a continuous injection using a dual-chamber injection system according to several embodiments. [Figure 81] Figure 81 is a detailed longitudinal cross-sectional view of a dual-chamber safe continuous injection system according to several embodiments. [Figure 82] Figure 82 is a schematic diagram of various steps of injection using a dual-chamber injection system according to several embodiments. [Figure 83]Figure 83A is a detailed perspective view of a fluid transfer assembly according to several embodiments. Figure 83B is a detailed perspective view of the proximal portion of a fluid transfer assembly according to several embodiments. [Figure 84] Figure 84 is a detailed perspective view of the proximal portion of a fluid transfer assembly according to several embodiments. [Figure 85] Figure 85 is a schematic diagram of various steps of a continuous injection using a dual-chamber injection system according to several embodiments. [Figure 86] Figure 86 is a perspective view of a dual-chamber injection system with a flow regulator according to several embodiments. [Figure 87] Figure 87 is a detailed perspective view of a dual-chamber injection system with a flow regulator according to several embodiments. [Figure 88] Figure 88 is a detailed perspective view of a dual-chamber injection system with a flow regulator according to several embodiments. [Figure 89] Figure 89 is a detailed perspective view of a dual-chamber injection system with a flow regulator according to several embodiments. [Figure 90] Figure 90 is a detailed perspective view of a dual-chamber injection system with a flow regulator according to several embodiments. [Figure 91] Figure 91 is a detailed perspective view of a dual-chamber injection system with a flow regulator according to several embodiments. [Figure 92] Figure 92 is a longitudinal cross-sectional view of varying levels of detail illustrating a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 93] Figure 93 is a longitudinal cross-sectional view of varying levels of detail illustrating a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 94] Figure 94 is a longitudinal cross-sectional view of varying levels of detail illustrating a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 95] Figure 95 is a longitudinal cross-sectional view of varying levels of detail illustrating a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 96] Figure 96 is a longitudinal cross-sectional view of varying levels of detail illustrating a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 97] Figure 97 is a longitudinal cross-sectional view of varying levels of detail illustrating a safe continuous injection method using a pre-filled dual-chamber continuous safety injection system according to several embodiments. [Figure 98] Figure 98 is a perspective view of a needle hub assembly according to several embodiments. [Figure 99] Figure 99 is a perspective view of a needle assembly according to several embodiments. [Figure 100] Figure 100 is a detailed perspective view of the needle proximal member of a needle assembly according to several embodiments. [Figure 101] Figure 101 shows perspective views and longitudinal cross-sectional views of needle proximal members according to several embodiments. [Figure 102] Figure 102 shows perspective views and longitudinal cross-sectional views of the needle proximal member according to several embodiments. [Figure 103] Figures 103A and 103B are axial cross-sectional views of the distal ends of two needle proximal members according to several embodiments. [Figure 104] Figure 104 is a longitudinal cross-sectional view of varying levels of detail illustrating a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 105] Figure 105 is a longitudinal cross-sectional view of varying levels of detail illustrating a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 106] Figure 106 is a longitudinal cross-sectional view of varying levels of detail showing a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 107]Figure 107 is a longitudinal cross-sectional view of varying levels of detail illustrating a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 108] Figure 108 is a longitudinal cross-sectional view of varying levels of detail showing a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 109] Figure 109 is a longitudinal cross-sectional view of varying levels of detail illustrating a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 110] Figure 110 shows perspective and exploded perspective views of fluid transfer assemblies according to several embodiments. [Figure 111] Figure 111 shows perspective and exploded perspective views of fluid transfer assemblies according to several embodiments. [Figure 112] Figures 112A to 112C show perspective views, longitudinal cross-sectional views, and axial cross-sectional views of fluid transfer proximal members according to several embodiments. [Figure 113] Figure 113 is a longitudinal cross-sectional view of varying levels of detail showing a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 114] Figure 114 is a longitudinal cross-sectional view of varying levels of detail illustrating a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 115] Figure 115 is a longitudinal cross-sectional view of varying levels of detail showing a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 116] Figure 116 is a longitudinal cross-sectional view of varying levels of detail illustrating a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 117] Figure 117 is a longitudinal cross-sectional view of varying levels of detail illustrating a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 118] Figure 118 is a longitudinal cross-sectional view of varying levels of detail illustrating a continuous injection method using a pre-filled needleless dual-chamber continuous injection system according to several embodiments. [Figure 119] Figure 119 is a perspective view of a fluid transfer assembly according to several embodiments. [Figure 120] Figure 120 is a perspective view of a fluid transfer assembly according to several embodiments. [Figure 121] Figures 121A to 121C are longitudinal and axial cross-sectional views of the fluid transfer area in several embodiments. [Figure 122] Figure 122 is a perspective view of a fluid transfer assembly according to several embodiments. [Figure 123] Figure 123 is a perspective view of a fluid transfer assembly according to several embodiments. [Figure 124] Figure 124 is a detailed longitudinal cross-sectional view of an injection system including a fluid transfer joint member / part according to several embodiments. [Figure 125] Figures 125A and 125B are perspective and exploded perspective views of fluid transfer joint members / parts according to several embodiments. [Figure 126] Figures 126A and 126B are perspective and top views of fluid transfer distal anchors of fluid transfer joint members / parts according to several embodiments. [Figure 127] Figures 127A and 127B are perspective and side views of biasing members for fluid transfer joint members / parts according to several embodiments. [Figure 128] Figure 128 is a detailed longitudinal cross-sectional view of an injection system including a fluid transfer joint member / part according to several embodiments. [Figure 129] Figures 129A and 129B show perspective views, exploded perspective views, and exploded side views of fluid transfer joint members / parts according to several embodiments. [Figure 130] Figure 130 shows perspective views, exploded perspective views, and exploded side views of fluid transfer joint members / parts according to several embodiments. [Figure 131]Figure 131 is a detailed longitudinal cross-sectional view of an injection system including a fluid transfer coupling member / part according to several embodiments. [Figure 132] Figures 132A and 132B are perspective and side views of fluid transfer joint members / parts according to several embodiments. [Figure 133] Figure 133 is a detailed longitudinal cross-sectional view of an injection system including a fluid transfer joint member / part according to several embodiments. [Figure 134] Figures 134A and 134B show perspective views, exploded perspective views, and longitudinal cross-sectional views of fluid transfer joint members / parts according to several embodiments. [Figure 135] Figure 135 shows perspective views, exploded perspective views, and longitudinal cross-sectional views of fluid transfer joint members / parts according to several embodiments. [Figure 136] Figure 136 is a longitudinal cross-sectional view of a fluid transfer assembly installed inside a syringe body according to several embodiments. [Figure 137] Figure 137 shows perspective and longitudinal cross-sectional views of fluid transfer assemblies according to several embodiments. [Figure 138] Figure 138 shows perspective and longitudinal cross-sectional views of fluid transfer assemblies according to several embodiments. [Figure 139] Figures 139A to 139C show perspective views, axial cross-sectional views, and longitudinal cross-sectional views of fluid transfer proximal members according to several embodiments. [Figure 140] Figure 140 is a series of side views illustrating the assembly steps of a fluid transfer assembly according to several embodiments. [Figure 141] Figure 141 is a longitudinal cross-sectional view of a fluid transfer assembly installed inside a syringe body according to several embodiments. [Figure 142] Figure 142 is a perspective view showing the steps of assembling a fluid transfer assembly according to several embodiments. [Figure 143] Figure 143 is a longitudinal cross-sectional view of a fluid transfer coupling member / part installed inside a syringe body according to several embodiments. [Figure 144] Figures 144A and 144B are a series of perspective and longitudinal cross-sectional views illustrating the assembly steps of fluid transfer joint members / parts according to several embodiments. [Figure 145] Figures 145A to 145C are a series of perspective and longitudinal cross-sectional views illustrating the assembly steps of fluid transfer joint members / parts according to several embodiments. [Figure 146] Figure 146 shows a longitudinal section view and a detailed longitudinal section view of a dual-chamber safety injection system including a one-way valve according to several embodiments. [Figure 147] Figure 147 shows a longitudinal section view and a detailed longitudinal section view of a dual-chamber safety injection system including a one-way valve according to several embodiments. [Figure 148] Figures 148A to 148C are perspective, side, and exploded views of the use of a one-way valve for use in a dual-chamber safety injection system according to several embodiments.

[0067] To better understand how the various embodiments achieve the above and other advantages and objectives, a more detailed description of the embodiments is given with reference to the accompanying drawings. It should be noted that the drawings are not drawn to actual size, and similar structural or functional elements are represented by similar reference numerals throughout. It will be understood that these drawings depict only specific illustrative embodiments and should therefore not be considered as limiting the scope of the embodiments. [Modes for carrying out the invention]

[0068] Exemplary pre-filled multi-chamber continuous injection system and method I. Dual-chamber safety injection system and method Figures 6A, 6B, and 7 are longitudinal side view, longitudinal section view, and detailed longitudinal section view showing a pre-filled dual-chamber continuous safety injection system (100) according to several embodiments. The pre-filled dual-chamber continuous safety injection system (100) includes a conventional readily available pre-filled syringe body (34) in which conventional readily available proximal and distal stopper members (32, 36) are disposed. The proximal and distal stopper members (32, 36), together with the syringe body (34), define the proximal and distal chambers (40, 42). The first and second liquids (252, 254) are contained in the distal and proximal chambers (42, 40), respectively. The proximal and distal stopper members (32, 36) close the proximal and distal ends of the proximal chamber (40). The distal stopper member (36) closes the proximal end of the distal chamber (42). In some embodiments, the distal surface of the proximal stopper member (32) and the proximal surface of the distal stopper member (36) are each coated with a lubricating polymer coating (e.g., PTFE or ETFE), and the first and second polymer coatings of the proximal and distal stopper members (32, 36), together with the syringe body (34), define the proximal chamber (40). The lubricating polymer coating also serves to isolate the rubber of the proximal and distal stopper members (32, 36) from the second liquid (254). The proximal stopper member and the distal stopper member (32, 36) may be oriented as shown in Figures 6A and 6B, or the distal stopper (36) may be inverted so that the lubricating coating faces the distal chamber (42) so that the first liquid (252) in the distal chamber (42) comes into contact with the lubricating coating for storage.

[0069] A needle hub assembly (606) is positioned at the distal end of the distal chamber (42). The needle hub assembly (606) includes a needle hub (608) and a needle spine assembly ("needle") (76) detachably coupled thereto. In some embodiments, a needle cover member (not shown) may be placed on the needle hub assembly (606) for storage. The dual-chamber continuous safety injection system (100) facilitates the continuous injection of a first fluid (252) from the distal chamber (42) and then a second fluid (254) from the proximal chamber (40) when the plunger assembly (44) is continuously inserted into the syringe body (34) to varying degrees by the user. The plunger assembly (44) includes a plunger housing member (69) coupled to a proximal stopper member (32) and a plunger operating interface (128). The first and second liquids (252, 254) located in the distal and proximal chambers (42, 40), respectively, may be any liquid or gel, such as an aqueous or oily drug solution.

[0070] The dual-chamber continuous safety injection system (100) has a crimped needle configuration in which, when presented to the user, the needle hub assembly (606) is mounted in a ready-to-inject position after removing a needle cover member (not shown) which may include elastic sealing material on its inner surface to interface with the distal end (78) and / or distal hub (608) of the needle during storage. Although the crimped needle is shown mounted in a fixed position, the crimped needle can be removably coupled to the syringe body (34) using a Luer slip or Luer lock interface (not shown), with the proximal end (50, see Figure 7) of the needle (76) extending into the distal chamber (42) through the Luer interface. Alternatively, the needle may be fixedly or removably mounted to a flange on the cartridge body instead of the syringe.

[0071] The needle (76) includes a proximal end (50, see Figure 7) and a distal end (78, see Figures 6A and 6B) connected to opposing ends (i.e., the respective proximal and distal ends) of a needle connector member (83, see Figure 7). The needle connector member (83) is a tubular member connected to the sharp distal end (78), which also defines a distal opening (81). The needle connector member (83) also defines a proximal opening and an intermediate opening (85, 80). The intermediate opening (80) is located adjacent to the distal end of the syringe body (34). The proximal opening (85) is located adjacent to the proximal end of the needle connector member (83). The proximal end (50) is a solid proximal end feature.

[0072] As shown in Figure 12, the distal end (87) of the proximal end (50) of the solid needle is located inside the tubular needle connector (83). The proximal end (89) of the tubular needle connector (83) is welded to the proximal end (50) of the solid needle by fillet welding. The proximal end (89) of the tubular needle connector (83) is tapered in the proximal direction to facilitate the needle (76) through the rubber stopper, such as the distal stopper member (36), while reducing or eliminating the cutting / shredding of the rubber stopper (as described herein). Otherwise, the cutting / shredding of the rubber stopper could generate undesirable rubber particles that could interfere with the injection system and / or be injected into the patient. The proximal and distal edges (91) of the proximal opening (85) may also be rounded (e.g., by tumbling or grinding) to reduce or eliminate the cutting / shredding of the rubber stopper during its passage.

[0073] As also shown in Figure 12, the distal end (87) of the proximal end (50) of the solid needle and the tubular needle connecting member (83) define an annular lumen (93). The annular lumen (93) fluidly couples the proximal opening (85) to the interior of the needle (76), the intermediate opening (80, see Figure 7), and the distal opening (81). By fluidly coupling the proximal opening (85) to the interior of the needle through the annular lumen (93), it becomes possible to position the proximal opening (85) in close proximity to the proximal end (89) of the tubular needle connecting member (83), thereby enabling a more compact system design. By fluidly coupling the proximal opening (85) to the inside of the needle through the annular lumen (93), and by allowing a larger portion of the distal end (87) of the proximal end (50) of the solid needle to be positioned inside the tubular needle connector (83), the manufacturing of a pre-filled dual-chamber continuous safety injection system (100) is facilitated.

[0074] As also shown in Figure 12, the proximal opening (85) is an elongated slot that can be formed within the tubular needle joint member (83) using a grinding wheel. The use of a grinding wheel facilitates mass production of the tubular needle joint member (83). The length of the proximal opening (85) is configured to provide a tolerance for variations related to the proximal stopper member and / or distal stopper member (32, 36). Variations related to the proximal stopper member and / or distal stopper member (32, 36) may be distortion of the proximal surface of the distal stopper member, the position of the proximal stopper member relative to the elongated slot, and / or the position of the distal stopper member relative to the elongated slot (as described herein). The length of the proximal opening (85) also minimizes or eliminates backflow leakage of the first and second fluids (252, 254) to the plunger. In some embodiments, the length of the proximal opening (85) is about 1 / 32 inch to about 1 / 16 inch. The proximal and distal edges (91) of the proximal opening (85) may also be rounded (e.g., by tumbling or grinding) to reduce or eliminate cutting / shredding of the rubber stopper during penetration, as described herein.

[0075] In short, additional components of the dual-chamber continuous safety injection system (100) include a retraction system, needle retention features, energy storage members (e.g., springs), and energy storage member latches within the plunger member (44). In the embodiments shown in Figures 6A to 24, a substantial portion of the safety needle retraction hardware resides within the plunger housing (69). Additional components also include needle holder members (e.g., O-rings, needle latches, and / or detents) within the needle hub (608). Further additional components include a funnel within the distal stopper member (36) for guiding the proximal end of the needle (50) to the center of the distal stopper member (36).

[0076] Figures 6A to 18 illustrate safe continuous injection methods using the pre-filled dual-chamber continuous safety injection system (100) described herein, according to several embodiments. Figures 6A, 6B, and 7 show the pre-filled dual-chamber continuous safety injection system (100) in a first / ready-to-use configuration. The only difference between the first / ready-to-use configuration and the factory-shipped configuration (not shown) is that a needle cover member (not shown) present in the factory-shipped configuration is removed in the first / ready-to-use configuration. In the first / ready-to-use configuration, the proximal opening (85) is located within the distal chamber (42) together with the intermediate opening (80). Therefore, there is no flow path between the proximal chamber (40) and the distal opening (81). Therefore, any distal force applied to the plunger operating interface (128) is transferred through the plunger member (44), the proximal stopper member (32), and the incompressible second liquid (254) in the proximal chamber (40), causing the distal stopper member (36) to move distally relative to the syringe body (34). As the distal stopper member (36) moves distally relative to the syringe body (34), the pressure in the distal chamber (42) increases, which drives the first liquid (252) out of the distal chamber (42) through the intermediate and proximal openings (80, 85) and out of the distal opening (81).

[0077] Figures 8A, 8B, and 9 show the filled dual-chamber continuous safety injection system (100) after the distal stopper member (36) has been moved distally by a first distance relative to the syringe body (34). The distal chamber (42) has been partially crushed / reduced in size, and a portion of the first fluid (252) has been discharged from the filled dual-chamber continuous safety injection system (100) through the distal opening (81). The distal stopper member (36) has also been moved distally relative to the syringe body (34), causing the proximal end (50) of the needle (76) to penetrate the distal stopper member (36). As shown in Figure 9, the rubber material on which the distal stopper member (36) is made is deformed / protruded proximally when the proximal end (50) of the needle (76) penetrates the distal stopper member (36) in the proximal direction, due to friction between the distal stopper member (36) and the proximal end (50). This friction can be reduced by adding lubricants to the various components of the filled dual-chamber continuous safety injection system (100). The proximal opening (85) is still located within the distal chamber (42) or is blocked by the distal stopper member (36). Therefore, there is no flow path between the proximal chamber (40) and the distal opening (81), and the distal force applied to the plunger operating interface (128) is still transmitted to the distal stopper member (36) as described above.

[0078] Figures 10A, 10B, 11, and 12 show the filled dual-chamber continuous safety injection system (100) after the distal stopper member (36) has been moved distally by a second distance (further than the first distance) relative to the syringe body (34). The distal chamber (42) is almost completely crushed / almost completely ejected, and most of the first fluid (252) has been discharged from the filled dual-chamber continuous safety injection system (100) through the distal opening (81). Further distal movement of the distal stopper member (36) relative to the syringe body (34) also causes the proximal end (50) of the needle (76) to further penetrate the distal stopper member (36). As shown in Figures 11 and 12, the rubber material on which the distal stopper member (36) is made is deformed / protruded in the proximal direction when the proximal end (50) of the needle (76) penetrates the distal stopper member (36) in the proximal direction due to friction between the distal stopper member (36) and the proximal end (50). Also as shown in Figures 11 and 12, as the proximal end (50) of the needle (76) penetrates further, the proximal opening (85) is now positioned within the proximal chamber (40). Therefore, at this point, a flow path exists between the proximal chamber (40) and the distal opening (81), and the distal force applied to the plunger operating interface (128) moves the proximal stopper member (32) distal to the syringe body (34), causing the second liquid (254) to be discharged from the proximal chamber (40). Opening the flow path between the proximal chamber (40) and the distal opening (81) gives the filled dual-chamber continuous safety injection system (100) a second configuration that allows the second fluid (254) to be discharged from the proximal chamber (40).

[0079] As shown in Figure 12, the length of the proximal opening (85) provides a tolerance for variations in the degree of deformation / protrusion of the distal stopper member (36) when the proximal end (50) of the needle (76) penetrates the distal stopper member (36) in the proximal direction. In particular, even if the distal stopper member (36) is deformed / protruded more than expected, the proximal opening (85) still fluidly couples with the proximal chamber (40) at the distal opening (81). Figure 12 also shows that the proximal end (89) of the tubular needle joint member (83) is welded to the solid needle proximal end (50) by a fillet corner weld, and the proximal end (89) is tapered in the proximal direction to facilitate the needle (76) penetrating the distal stopper member (36) while reducing or eliminating the possibility of cutting / fractionating the distal stopper member (36). Otherwise, cutting / shredding of the rubber stopper could create undesirable rubber particles that could interfere with the injection system and / or be injected into the patient. The proximal and distal edges (91) of the proximal opening (85) can also be rounded (e.g., by tumbling or grinding) to reduce or eliminate cutting / shredding of the distal stopper member (36) during penetration.

[0080] Figures 13A, 13B, and 14 show the filled dual-chamber continuous safety injection system (100) after the proximal stopper member (32) has been moved distally by a first distance relative to the syringe body (34). The proximal chamber (40) has been partially crushed / reduced in size, and some of the second fluid (254) has been discharged from the filled dual-chamber continuous safety injection system (100) through the distal opening (81). As shown in Figure 14, the proximal opening (85) is inside the proximal chamber (40), so at this point, a flow path exists between the proximal chamber (40) and the distal opening (81). The flow path between the proximal chamber (40) and the distal opening (81) allows the proximal stopper member (32) to move distally toward the distal stopper member (36) by discharging a portion of the second fluid (254) through the proximal opening (85). The distal force applied to the plunger operating interface (128) is transmitted to move the proximal stopper member (32), so the distal stopper member (36) is substantially stopped moving at this point.

[0081] Figures 15A, 15B, and 16 show the filled dual-chamber continuous safety injection system (100) after the proximal stopper member (32) has been moved distally by a second distance (further than the first distance) relative to the syringe body (34). The proximal chamber (40) is completely collapsed / removed, and substantially the entire volume of the second fluid (254) has been discharged from the filled dual-chamber continuous safety injection system (100) through the distal opening (81). Further distal movement of the proximal stopper member (32) relative to the syringe body (34) also causes the proximal end (50) of the needle (76) to penetrate the proximal stopper member (32) and enter the plunger assembly (44). Penetration of the proximal stopper member (32) causes the proximal end (50) of the needle (76) to be captured by the needle retention feature.

[0082] As shown in Figure 16, the length of the proximal opening (85) provides tolerance for variations in the positions of the proximal and distal stopper members (32, 36) when the proximal chamber (40) is crushed. In particular, even if the proximal and distal stopper members (32, 36) are positioned slightly differently when the proximal chamber (40) is crushed, the proximal opening (85) still fluidly couples with the proximal chamber (40) at the distal opening (81). The length of the proximal opening (85) is also configured to prevent backflow leakage of the first and second fluids (252, 254) into the plunger assembly (44) by limiting the distance between the proximal opening (85) and the proximal end (50) of the solid needle, so that the proximal opening (85) never enters the plunger assembly (44).

[0083] Figures 17A, 17B, and 18 show the filled dual-chamber continuous safety injection system (100) after the proximal stopper member (32) has been moved distally by a third distance (further than the first and second distances) relative to the syringe body (34). As the proximal end (50) of the needle (76) is moved further proximal to the plunger assembly (44), the energy storage member latch is activated, releasing the energy storage member (spring), which pulls / retracts the needle (76) at least partially toward the plunger assembly (44), positioning the sharp distal end (78) of the needle (76) inside the syringe body (34). The retraction of the needle (76) makes the filled dual-chamber continuous safety injection system (100) a safe configuration for disposal after injection.

[0084] Figures 19A–22 show later portions of the safe continuous injection method using the pre-filled dual-chamber continuous safety injection system (100') described herein, according to several embodiments. Figures 19A, 19B, and 20 show the pre-filled dual-chamber continuous safety injection system (100') in the middle of the safe continuous injection method, in steps similar to those of the method shown in Figures 15A, 15B, and 16, using system (100). One difference between the pre-filled dual-chamber continuous safety injection systems (100, 100') is that the proximal end (50') and needle (76') of system (100') are longer than the corresponding proximal end (50) and needle (76) of system (100). Thus, the proximal opening (85) of system (100') enters the proximal chamber (not shown, see (40) in Figure 7) before the distal chamber (42) substantially collapses. Therefore, during the steps corresponding to those in Figures 6A to 14, only the first portion of the first liquid (252) is discharged from the distal chamber (42). As shown in Figure 20, when the proximal chamber (40) is completely collapsed / removed and substantially the entire amount of the second liquid (254) is discharged from the filled dual-chamber continuous safety injection system (100) through the distal opening (81), the second portion of the first liquid (252) remains in the distal chamber (42).

[0085] Figures 21A, 21B, and 22 show a filled dual-chamber continuous safety injection system (100') after the proximal and distal stopper members (32, 36) have been moved a certain distance distal to the syringe body (34). As the proximal and distal stopper members (32, 36) move distally to the syringe body (34), the second portion of the first liquid (252) is discharged from the distal chamber (42) through the intermediate opening (80). The discharge / injection pattern in the embodiments shown in Figures 19A to 22 is the first portion of the first liquid (252) in the distal chamber (42), followed by substantially the entirety of the second liquid (254) in the proximal chamber (40), and finally the second portion of the first liquid (252) in the distal chamber (42). After the second portion of the first liquid (252) is discharged, the needle (76') is at least partially retracted into the plunger assembly (44), as shown in Figures 17A, 17B, and 18 and described above. Specific portions of the first liquid (252) are shown in Figures 19A to 22, but the dimensions of the various portions of the needle (76') can be modified to adjust the portion of the first liquid (252).

[0086] Figures 23A, 23B, and 24 show a pre-filled dual-chamber continuous safety injection system (100") in a first / ready-to-use configuration according to several embodiments. Various components of the pre-filled dual-chamber continuous safety injection system (100") may be identical to the corresponding components of the pre-filled dual-chamber continuous safety injection system (100) shown in Figures 6A to 18. One difference between the pre-filled dual-chamber continuous safety injection systems (100, 100") is that the system (100") shown in Figures 23A, 23B, and 24 has a larger distal chamber (42") compared to the distal chamber (42) of the system (100) shown in Figures 6A to 18. Thus, the system (100") is configured to inject more of the first liquid (252) from the larger distal chamber (42). In fact, the distal chamber (42") is larger because more of the first liquid (252) is added during the manufacture of the system (100). The system (100") can be used to continuously inject the first liquid and the second liquid (252, 254) in a manner similar to that shown in Figures 6A to 18 and described above.

[0087] As shown in the pre-filled dual-chamber continuous safety injection system (100, 100', 100"), the various components of the system (100, 100', 100") and their positions can be modified to adjust the amounts of the first and second liquids (252, 254) injected, including portions of the first liquid (252) that can be injected before and after the second liquid (254).

[0088] II. Triple Chamber Injection System and Method Figures 25A, 25B, and 26 are longitudinal side view, longitudinal section view, and detailed longitudinal section view showing a pre-filled triple-chamber continuous injection system (200) according to several embodiments. The pre-filled triple-chamber continuous injection system (200) includes a conventional readily available pre-filled syringe body (34) in which conventional readily available proximal stopper members, intermediate stopper members, and distal stopper members (32, 33, 36) are disposed inside. The proximal stopper members, intermediate stopper members, and distal stopper members (32, 33, 36) together with the syringe body (34) define the proximal chamber, intermediate chamber, and distal chamber (40, 41, 42). A first liquid, a second liquid, and a third liquid (252, 253, 254) are contained in the distal chamber, intermediate chamber, and proximal chamber (42, 41, 40), respectively. The proximal stopper member and the intermediate stopper member (32, 33) close the proximal and distal ends of the proximal chamber (40). The intermediate stopper member and the distal stopper member (33, 36) close the proximal and distal ends of the intermediate chamber (41). The distal stopper member (36) closes the proximal end of the distal chamber (42). In some embodiments, the various surfaces of the proximal stopper member, the intermediate stopper member, and the distal stopper member (32, 33, 36) are each coated with a lubricating polymer coating (e.g., PTFE or ETFE), and as a result, the coating, together with the syringe body (34), defines the distal chamber, the intermediate chamber, and the proximal chamber (42, 41, 40). The lubricating polymer coating also serves to isolate the rubber of the proximal stopper member, intermediate stopper member, and distal stopper member (32, 33, 36) from the first liquid, second liquid, and third liquid (252, 253, 254), respectively. The proximal stopper member, intermediate stopper member, and distal stopper member (32, 33, 36) may be oriented as shown in Figures 6A and 6B, or the distal stopper (36) may be inverted.

[0089] A needle hub assembly (606) is positioned at the distal end of the distal chamber (42). The needle hub assembly (606) includes a needle hub (608) and a needle spine assembly ("needle") (76) coupled thereto. In some embodiments, a needle cover member (not shown) may be placed on the needle hub assembly (606) for storage. The pre-filled triple-chamber continuous injection system (200) facilitates the continuous injection of a first portion of the first fluid (252) from the distal chamber (42), then the second fluid (253) from the intermediate chamber (41), then the remaining portion of the first fluid (252) from the distal chamber (42), and then the third fluid (254) from the proximal chamber (40), as the plunger assembly (44) is continuously inserted into the syringe body (34) to varying degrees by the user. The plunger assembly (44) is coupled to the proximal stopper member (32) and includes a plunger operating interface (128). The first, second, and third liquids (252, 253, 254) located in the distal chamber, intermediate chamber, and proximal chamber (42, 41, 40), respectively, may be any liquid or gel, such as an aqueous or oily drug solution.

[0090] The pre-filled triple-chamber continuous injection system (200) has a crimped needle configuration in which, when presented to the user, the needle hub assembly (606) is mounted in a ready-to-inject position after removing a needle cover member (not shown) which may include elastic sealing material on its inner surface to interface with the distal end (78) and / or distal hub (608) during storage. Although the crimped needle is shown mounted in a fixed position, the crimped needle can be removably coupled to the syringe body (34) using a Luer slip or Luer lock interface (not shown), with the proximal end (50, see Figure 26) of the needle (76) extending into the distal chamber (42) through the Luer interface. Alternatively, the needle may be fixedly or removably mounted to a flange on the cartridge body instead of the syringe.

[0091] The needle (76) includes a proximal end (50, see Figure 26) and a distal end (78, see Figures 6A and 6B) connected to opposing ends (i.e., the respective proximal and distal ends) of a needle connector member (83, see Figure 7). The needle connector member (83) is a tubular member connected to the sharp distal end (78), which also defines a distal opening (81). The needle connector member (83) also defines a proximal opening and an intermediate opening (85, 80). The intermediate opening (80) is located adjacent to the distal end of the syringe body (34). The proximal opening (85) is located adjacent to the proximal end of the needle connector member (83). The proximal end (50) is a solid proximal end feature.

[0092] The pre-filled triple-chamber continuous injection system (200) contains many of the same components as the pre-filled dual-chamber continuous safety injection system (100) shown in Figures 6A to 18, and is assembled in a similar manner to the pre-filled dual-chamber continuous safety injection system (100). For example, the tubular needle joint member (83) is welded to the proximal end (50) of a solid needle by a fillet weld configured to facilitate the needle (76) through a rubber stopper such as a distal stopper member (36) while reducing or eliminating the cutting / shredding of the rubber stopper (as described herein). The proximal and distal edges of the proximal opening (85) may also be rounded (e.g., by tumbling or grinding) to reduce or eliminate the cutting / shredding of the rubber stopper during its passage.

[0093] An elongated slot can be formed within the tubular needle joint member (83) using a grinding wheel. The use of a grinding wheel facilitates mass production of the tubular needle joint member (83). The length of the proximal opening (85) is configured to provide tolerance for variations related to the proximal stopper member, intermediate stopper member, and / or distal stopper member (32, 33, 36). Variations related to the proximal stopper member, intermediate stopper member, and / or distal stopper member (32, 33, 36) may be distortion of the proximal surface of the distal stopper member, distortion of the proximal surface of the intermediate stopper member, position of the proximal stopper member relative to the elongated slot, position of the intermediate stopper member relative to the elongated slot, and / or position of the distal stopper member relative to the elongated slot (as described herein). In some embodiments, the length of the proximal opening (85) is about 1 / 16 inch to about 1 / 8 inch. The proximal and distal edges of the proximal opening (85) may also be rounded (e.g., by tumbling or grinding) to reduce or eliminate cutting / shredding of the rubber stopper during penetration, as described herein.

[0094] The additional components further include a funnel within the distal stopper member (36) for guiding the proximal end (50) of the needle to the center of the distal stopper member (36).

[0095] Figures 25A to 36 illustrate a continuous injection method using the pre-filled triple-chamber continuous injection system (200) described herein, according to several embodiments. Figures 25A, 25B, and 26 show the pre-filled triple-chamber continuous injection system (200) in a first / ready-to-use configuration. The only difference between the first / ready-to-use configuration and the factory-shipped configuration (not shown) is that a needle cover member (not shown) present in the factory-shipped configuration is removed in the first / ready-to-use configuration. In the first / ready-to-use configuration, the proximal opening (85) is located within the distal chamber (42) together with the intermediate opening (80). Therefore, there is no flow path between the intermediate and proximal chambers (41, 40) and the distal opening (81). Therefore, any distal force applied to the plunger operating interface (128) is transferred through the plunger member (44), the proximal stopper member (32), the incompressible third liquid (254) in the proximal chamber (40), the intermediate stopper member (33), and the incompressible second liquid (253) in the intermediate chamber (41), causing the distal stopper member (36) to move distally relative to the syringe body (34). As the distal stopper member (36) moves distally relative to the syringe body (34), the pressure in the distal chamber (42) increases, which drives the first liquid (252) out of the distal chamber (42) through the intermediate and proximal openings (80, 85) and out of the distal opening (81).

[0096] Figures 27A, 27B, and 28 show the filled triple-chamber continuous injection system (200) after the distal stopper member (36) has been moved distally by a first distance relative to the syringe body (34). The distal chamber (42) has been partially crushed / reduced in size, and a portion of the first fluid (252) has been discharged from the filled triple-chamber continuous injection system (200) through the distal opening (81). The distal stopper member (36) has also been moved distally relative to the syringe body (34), causing the proximal end (50) of the needle (76) to penetrate the distal stopper member (36). As shown in Figure 28, the rubber material on which the distal stopper member (36) is made is deformed / protruded proximally when the proximal end (50) of the needle (76) penetrates the distal stopper member (36) proximally, due to friction between the distal stopper member (36) and the proximal end (50). This friction can be reduced by adding lubricants to the various components of the filled triple-chamber continuous injection system (200). The proximal opening (85) is still located within the distal chamber (42) or is blocked by the distal stopper member (36). Therefore, there is no flow path between the intermediate chamber (41) and the distal opening (81), and the distal force applied to the plunger operating interface (128) is still transmitted to the distal stopper member (36) as described above.

[0097] Figures 29A, 29B, and 30 show the filled triple-chamber continuous injection system (200) after the distal stopper member (36) has been moved distally by a second distance (further than the first distance) relative to the syringe body (34). The distal chamber (42) is further compressed, and a first portion of the first fluid (252) is discharged from the filled triple-chamber continuous injection system (200) through the distal opening (81). Further distal movement of the distal stopper member (36) relative to the syringe body (34) also causes the proximal end (50) of the needle (76) to further penetrate the distal stopper member (36). As shown in Figure 30, the rubber material on which the distal stopper member (36) is made is deformed / protruded in the proximal direction when the proximal end (50) of the needle (76) penetrates the intermediate stopper member (33) in the proximal direction, due to friction between the distal stopper member (36) and the proximal end (50). Also as shown in Figure 30, as the proximal end (50) of the needle (76) penetrates the distal stopper member (36), the proximal opening (85) is positioned within the intermediate chamber (41) at this point. Therefore, at this point, a flow path exists between the intermediate chamber (41) and the distal opening (81), and the distal force applied to the plunger operating interface (128) moves the intermediate stopper member (33) distally relative to the syringe body (34), causing the second liquid (253) to be discharged from the intermediate chamber (41). Opening the flow path between the intermediate chamber (41) and the distal opening (81) gives the filled triple-chamber continuous injection system (200) a second configuration that allows the second liquid (253) to be discharged from the intermediate chamber (41).

[0098] Figures 31A, 31B, and 32 show the filled triple-chamber continuous injection system (200) after the intermediate stopper member (33) has been moved distally relative to the syringe body (34) until it contacts the distal stopper member (36). The intermediate chamber (41, see Figure 26) is collapsed, and substantially the entire volume of the second fluid (253) has been discharged from the filled triple-chamber continuous injection system (200) through the distal opening (81). Further distal movement of the intermediate stopper member (33) relative to the syringe body (34) also causes the proximal end (50) of the needle (76) to penetrate the intermediate stopper member (33). As shown in Figure 32, the rubber material on which the intermediate stopper member (33) is formed is deformed / protruded in the proximal direction when the proximal end (50) of the needle (76) penetrates the distal stopper member (36) in the proximal direction due to friction between the intermediate stopper member (33) and the proximal end (50). Also as shown in Figure 32, when the proximal end (50) of the needle (76) penetrates the intermediate stopper member (33), the proximal opening (85) is closed at this point by the intermediate stopper member and the distal stopper members (33, 36). Therefore, the only open channel in the system (200) is from the distal chamber (42) through the distal opening (80) to the distal opening, and the distal force applied to the plunger operating interface (128) at this point moves the intermediate stopper member and the distal stopper member (33, 36) distal to the syringe body (34) to discharge the second portion of the first liquid (252) from the distal chamber (42). Reopening the channel between the distal chamber (42) and the distal opening (81) results in a third configuration of the filled dual-chamber continuous safety injection system (100) that allows the second portion of the first liquid (252) to be discharged from the distal chamber (42).

[0099] Figures 33A, 33B, and 34 show the filled triple-chamber continuous injection system (200) after the intermediate and distal stopper members (33, 36) have been moved distally relative to the syringe body (34) until the distal stopper member (36) contacts the distal end of the syringe body (34). The distal chamber (42, see Figure 26) is collapsed, and substantially the entire volume of the first fluid (252) has been discharged from the filled triple-chamber continuous injection system (200) through the distal opening (81). Further distal movement of the intermediate stopper member (33) relative to the syringe body (34) also causes the proximal end (50) of the needle (76) to penetrate the intermediate stopper member (33). As also shown in Figure 34, the proximal end (50) of the needle (76) penetrates the intermediate stopper member (33), so that at this point the proximal opening (85) is positioned within the proximal chamber (40). Therefore, at this point, a flow path exists between the proximal chamber (40) and the distal opening (81), and the distal force applied to the plunger operating interface (128) moves the proximal stopper member (32) distally relative to the syringe body (34), causing the third liquid (254) to be discharged from the proximal chamber (40). The opening of the flow path between the proximal chamber (40) and the distal opening (81) creates a fourth configuration of the filled dual-chamber continuous safety injection system (100) that allows the third liquid (254) to be discharged from the proximal chamber (40).

[0100] Figures 35A, 35B, and 36 show the pre-filled triple-chamber continuous injection system (200) after the proximal stopper member (32) has been moved distally relative to the syringe body (34) until it contacts the intermediate stopper member (33). The proximal chamber (40, see Figure 26) is collapsed, and substantially the entire volume of the third fluid (254) has been discharged from the pre-filled triple-chamber continuous injection system (200) through the distal opening (81). Figures 35A, 35B, and 36 show the completed state of the continuous injection method using the pre-filled triple-chamber continuous injection system (200).

[0101] The dispensing / injection pattern of the embodiments shown in Figures 25A to 36 is a first portion of the first liquid (252) in the distal chamber (42), followed by substantially the entire amount of the second liquid (253) in the intermediate chamber (41), followed by a second portion of the first liquid (252) in the distal chamber (42), and finally substantially the entire amount of the third liquid (254) in the proximal chamber (40). While specific portions of the first liquid (252) are shown in Figures 25A to 36, the dimensions of various parts of the needle (76) can be modified to adjust the portion of the first liquid (252). Various components of the system (200) and their positions can be modified to adjust the amount of the first, second, and third liquids (252, 253, 254) injected, including the portion of the first liquid (252) that can be injected. The system (200) shown in Figures 25A to 36 did not include a safety needle retraction system, but the triple-chamber continuous injection system can be modified to include a safety needle retraction system. The system (200) shown in Figures 25A to 36 includes three chambers, but injection systems according to some embodiments may include four or more chambers.

[0102] Exemplary distal tube connector / retainer Figures 37 to 42 show a multi-chamber injection system (3700) including a distal tubular member (3783) connected to the distal end (3782) of a syringe body (3734) by a connector / retainer (3784). The distal end (3782) of the syringe body (3734) may be a Luer lock connector for connection to a needle (not shown). Figure 37 shows the distal end (3782) of the syringe body (3734) with a cap (3786) attached. Figure 38 shows the distal end (3782) of the syringe body (3734) without the cap (3786).

[0103] Figure 39 shows the connector / retainer (3784) in more detail. The connector / retainer (3784) includes a rhomboid portion (3788) and a flat portion (3790). The rhomboid portion (3788) is elastically compressible to fit inside the distal end (3782) of the syringe body (3734) from the proximal direction. Figures 41 and 42 show the insertion of the connector / retainer (3784), to which the distal tubular member (3783) is attached, into the distal end (3782) of the syringe body (3734) during assembly. When positioned inside the distal end (3782) of the syringe body (3734), the rhomboid portion (3788) is biased to expand to increase friction between the inner surface of the distal end (3782) of the syringe body (3734) and the rhomboid portion (3788) in order to resist longitudinal (e.g., proximal) movement of the connector / retainer (3784) and the distal tubular member (3783) coupled thereto relative to the syringe body (3734).

[0104] The flat portion (3790) of the connector / retainer (3784) is larger in at least one dimension than the opening in the distal end (3782) of the syringe body (3734). Therefore, the flat portion (3790) of the connector / retainer (3784) interferes with the distal end (3782) of the syringe body (3734) to restrict the distal movement of the connector / retainer (3784) and the distal tubular member (3783) coupled thereto relative to the syringe body (3734).

[0105] As shown in Figure 40, after assembly, a flow path (3792) opens between the inside of the syringe body (3734) and the outside past the connector / retainer (3784).

[0106] The connector / retainer (3784) may be cut or stamped as a single piece from a flat metal sheet (e.g., stainless steel), with the distal end of the rhombic portion (3788) located in the middle of the cut / stamped piece. The cut / stamped piece can then be bent to form the rhombic portion (3788). The material from which the cut / stamped piece is cut / stamped gives the rhombic portion (3788) elastic properties. Two pieces forming the flat portion (3790) can be overlapped. The free end of the flat portion (3790) may include one or more tongues configured to fit into a distal opening at the distal end of the distal tubular member (3783) to facilitate coupling (e.g., by welding) of the connector / retainer (3784) to the distal tubular member (3783).

[0107] III. Exemplary Safety Injection Systems Figures 43A and 43B show a single-chamber crimped needle safety injection system (600) according to several embodiments. The safety injection system (600) includes a needle hub assembly (610) coupled to a syringe body (620) and a plunger member (630) coupled to a stopper member (640) located inside the syringe body (620). The needle hub assembly (610) includes a needle assembly (650), such as one described later. The safety injection system (600) also includes a needle retraction system. The needle retraction system is located substantially inside the plunger member (630). The needle retraction system applies a proximal force to the needle assembly (650) after the injection is complete, pulling it at least partially inward into the needle hub assembly (610) and / or syringe body (620), so that the sharp distal tip (652) of the needle assembly (650) is positioned inside the needle hub assembly (610) and / or syringe body (620), preventing accidental needle stick injuries. In some embodiments, the proximal force is approximately 2 to 3 pounds.

[0108] Exemplary needle assembly Figures 44A to 58 show various needle assemblies and their features according to various embodiments.

[0109] Figure 44A shows a needle hub assembly (610) with a rigid needle shield (612) attached, according to several embodiments. Figure 44A also shows the proximal end of the needle assembly (650). Figure 44B shows a needle assembly (650) according to several embodiments.

[0110] Figure 45A is an exploded view of the needle assembly (650) shown in Figure 44B. The needle assembly (650) includes a proximal portion (660) and a distal portion (654), each configured to be partially positioned within the respective proximal and distal ends of an intermediate connector (670). The distal end of the distal portion (654) includes a sharp distal tip (652) configured to puncture target tissue for injection. The intermediate connector (670) includes an annular recess (672) configured to interfere with a needle latch to prevent the needle assembly (650) from being retracted proximal before the injection is completed.

[0111] The proximal portion (660) includes a proximal tip (680) at its proximal end and one or more longitudinal channels (662) extending from its distal end. Figure 45B is a longitudinal cross-sectional view of an intermediate connector (670) in which the proximal and distal portions (660, 654) are partially located, according to several embodiments. Figure 45B shows that the proximal portion (660) includes two longitudinal channels (662) formed within substantially opposing surfaces of the proximal portion (660). The longitudinal channels (662) enter the intermediate connector (670) from the outside of the needle assembly (650), then enter the distal portion (654), pass through a proximal opening (656) within the distal portion (654), and exit through the sharp distal tip (652) of the distal portion (654), forming two channels.

[0112] Figure 46 shows the proximal end of the intermediate connector (670), with the distal end of the proximal portion (660) inserted into the intermediate connector (670) until only the proximal end of the longitudinal channel (662) remains outside the intermediate connector (670). This proximal end of the longitudinal channel (662) forms an opening (664) that fluidly couples the inside and outside of the needle assembly (650).

[0113] Figures 47A and 47B are perspective and side views of the proximal portion (660) of a needle assembly (650) according to several embodiments. The proximal portion (660) may be formed by stamping a flat piece of sheet metal or metal wire to form various feature parts of the proximal portion (660) described herein. Forming the proximal portion (660) by stamping reduces manufacturing complexity and cost.

[0114] Figures 48A and 48B are perspective views of two proximal portions (660A and 660B) according to two embodiments. Figures 49A and 49B are detailed perspective views of the distal ends of the respective proximal portions (660A and 660B). Figures 50A and 50B are axial cross-sectional views of the distal ends of the respective proximal portions (660A and 660B).

[0115] As best illustrated in Figures 50A and 50B, the axial cross-sections of the distal ends of the proximal portions (660A, 660B) form crescent and dumbbell shapes, respectively. These crescent and dumbbell shapes define one and two longitudinal channels (662A, 662B), respectively. The longitudinal channels (662A, 662B) have rounded / circular cross-sections, which minimize fluid flow constraints through them. The circular cross-section is efficient for fluid flow because it minimizes fluid interaction with the channel walls, which would otherwise impose a zero-velocity boundary condition on the flowing fluid. Therefore, by minimizing wall exposure, the amount of shear resistance experienced by the fluid during flow is minimized. Hagen-Poiseuille equation:

[0116] According to TIFF2026065007000002.tif12170, the resistor of logic pipe 1400 (see Figure 51) is r 4Because it is inversely proportional, even if the cross-sectional area is maintained, the fluid flow resistance of a single round channel (662A) (see Figure 50A) can be lower than that of a double channel (662B) (see Figure 50B).

[0117] Even with the formation of longitudinal channels (662A, 662B) internally, the proximal portions (660A, 660B) have sufficient bending moment of inertia to improve stiffness and resistance to bending. In fact, the proximal portions (660A, 660B) are similar to steel I-beams and have similar stiffness characteristics. Resistance to bending is particularly important when the proximal portions (660A, 660B) drill through the stopper member (640). Minimizing bending when the proximal portions (660A, 660B) drill through the stopper member (640) increases the probability that the proximal tip (680) of the proximal portion (664) will be captured and the needle assembly (650) will be retracted (see Figures 58-62 and 63-66).

[0118] The diameters of the proximal portions (660A) and (660B) are also relatively large (e.g., about 0.026 inches compared to a cold-formed proximal portion having a diameter of about 0.020 inches). As a result of the larger diameter of the proximal portion (660), the overall bending moment of inertia is higher, the resistance to bending is greater, and this also improves the probability of capture. The proximal portions (660A) and (660B) are also very close in diameter to the intermediate portion (670), which may have a diameter of about 0.036 inches. Due to the similar diameters, the needle assembly (650) is more easily retracted through the stopper member during retraction, as the proximal opening of the intermediate portion (670) is less likely to get caught on the stopper member during retraction, resulting from the relatively small diameter difference between the intermediate portion (670) and the proximal portion (660).

[0119] Figures 52A and 52B are detailed perspective views of the distal ends of the proximal portions (660A, 660B), showing the cut-out sections of the intermediate connector (670) with their respective distal ends partially located internally. As shown in Figures 52A and 52B, the crescent and dumbbell cross-sectional shapes of the proximal portions (660A, 660B) provide a substantial amount of contact between the outer diameter of the proximal portions (660A, 660B) and the inner diameter of the tubular intermediate connector (670). This substantial amount of contact reduces the amount of welding force required to join the proximal portions (660A, 660B) and the tubular intermediate connector (670). The reduction in the amount of welding force required also minimizes the probability of channel occlusion resulting from crushed weld metal of the proximal portions (660A, 660B) and the tubular intermediate connector (670).

[0120] Figures 53 to 57 show the proximal tip (680) of the proximal portion (664) in more detail. The proximal tip (680) includes a pyramidal proximal puncture tip (682), a slightly tapered intermediate portion (684), and a toroidal distal flange (686). As shown in Figure 56, the pyramidal proximal puncture tip (682) includes four faces / lobes 683. As shown in Figure 53, the edges defining the lobes 683 of the pyramidal proximal puncture tip (682) form a tip with an angle of approximately 90° when viewed from the side. Compared to the more obtuse 90° angle tip, the intermediate portion (684) has a sharper taper of approximately 12° to 15°. The sharper taper of the intermediate portion (684) reduces the force required to puncture the stopper member.

[0121] The pyramidal proximal puncture tip (682) and the slightly tapered intermediate portion (684) form a composite tip shape of the proximal tip (680). The 90° pyramidal proximal puncture tip (682) may be convex and, in some embodiments, may be coated with a slippery hard coating, is configured to catch / grip the distal surface of the stopper member (640) without slipping off the distal surface of the stopper member (640). The 12° to 15° intermediate portion (684) is configured to reduce the puncture force required when the proximal tip (680) penetrates the stopper member (640) during puncture. The transition between the pyramidal proximal puncture tip (682) and the intermediate section (684) is smoothed, and is therefore configured to minimize snagging or sticking of the funnel components during capture of the proximal tip (680) by the proximal section (664) to allow for the retraction of the needle assembly (650) (see Figures 58-62 and 63-66).

[0122] The proximal portion (660) of the needle assembly (650) also includes a reduced diameter portion (664) located immediately distal to the proximal tip (680). In embodiments in which the proximal portion (660) of the needle assembly (650) is formed by stamping, the radial overhang between the outer diameter of the toroidal distal flange (686) and the reduced diameter portion (664) can be up to approximately 0.0075 inches. This relatively large overhang (compared to, for example, a cold-formed proximal tip) increases the probability and safety of the proximal tip (680) of the proximal portion (664) being caught, enabling the retraction of the needle assembly (650) (see Figures 58–62 and 63–66).

[0123] IV. Exemplary Safety Injection Systems Figures 58 to 62 illustrate injection and needle capture using the safety injection system (2100) according to several embodiments. Figure 58 shows the safety injection system (2100) in a pre-injection configuration, including a needle assembly (650) having a proximal portion (660) similar to that shown in the embodiments of Figures 53 to 57. The safety injection system (2100) includes a needle retraction system.

[0124] In Figure 59, the proximal tip (680) of the proximal portion (660) is about to puncture the stopper member (640), which is shown to have a convex distal surface. The 90° pyramidal proximal puncture tip (682) of the proximal tip (680) is configured to catch / grasp the distal surface (642) of the stopper member (640) without slipping off. As described above, the distal surface (642) of the stopper member (640) may also be coated with a slippery hard coating.

[0125] Figure 60 shows the continued distal movement of the stopper member (640) relative to the needle assembly (650). Needle retraction systems according to some embodiments include a funnel (632) configured to guide the proximal tip (680) to a needle catch cup (634). A smoothing transition between the pyramidal proximal puncture tip (682) and the intermediate portion (684) is configured to minimize snagging or sticking of the funnel (632) during the capture of the proximal tip (680) by the needle catch cup (634) of the proximal portion (664).

[0126] Figures 61 and 62 show the continued distal movement of the stopper member (640) relative to the needle assembly (650). The interaction between the proximal tip (680) and the funnel (632) guides the proximal tip (680) to the needle catch cup (634). The relatively large radial overhang (approximately 0.0075 inches) between the toroidal distal flange (686) of the proximal tip (680) and the tapered portion (664) increases the probability and safety of the proximal tip (680) being captured by the needle catch cup (634). The relatively large radial overhang also allows for a wider opening within the needle catch cup (634) without compromising the retention of the proximal tip (680) after capture. The wider opening and slightly tapered intermediate section (684) allow the proximal tip (680) to be inserted into the needle catch cup (634) without triggering the needle retraction mechanism (e.g., a spring release latch).

[0127] Figures 63–66 illustrate injection and needle capture using the safety injection system (2600) according to several embodiments. Figure 63 shows the safety injection system (2600) including a needle assembly (650) having a proximal portion (660) similar to that of the embodiments shown in Figures 53–57. The safety injection system (2600) includes a needle retraction system. The difference between the safety injection system (2100) shown in Figures 58–62 and the safety injection system (2600) shown in Figures 63–66 is that the safety injection system (2600) includes a pair of self-biasing tabs (634') that form a funnel (632') instead of the needle catch cup (634) shown in the safety injection system (2100). The pair of self-biasing tabs (634') are also molded to be trigger components to reduce the number of components (for example, for assembly).

[0128] Figure 63 shows a safety injection system (2600) in a pre-injection configuration, including a needle assembly (650) having a proximal portion (660) similar to that of the embodiments shown in Figures 53 to 57. The safety injection system (2600) includes a needle retraction system.

[0129] Figures 64–66 show injection and needle capture under distal motion of the stopper member (640) relative to the needle assembly (650). The interaction between the proximal tip (680) and the funnel (632') guides the proximal tip (680) to the proximal end of the pair of self-biasing tabs (634'). The relatively large radial overhang (approximately 0.0075 inches) between the outer diameter of the toroidal distal flange (686) of the proximal tip (680) and the tapered portion (664) increases the probability and safety of capture of the proximal tip (680) by the self-biasing tabs (634'). The self-biasing tabs (634') are separated by the side wall of the needle catch member and two slots (636) (see Figure 65) parallel to the longitudinal axis. Due to the configuration in which the slot (636) is parallel to the side wall of the needle catch member, the tab (634') is self-biasing in that when the proximal tip (680) is pulled distally to the tab (634'), the tab (634') is fastened around the reduced diameter portion (664) of the needle assembly (650). The rotation of the tab (634') and the funnel portion (632') distal to the slot (636) contributes to this self-biasing feature. The needle catch also includes a pair of windows 638 to facilitate the rotation of the tab (634').

[0130] The relatively large radial overhang also allows for a wider opening between the self-biasing tabs (634') without compromising the placement of the proximal tip (680) after capture. In embodiments with a relatively large radial overhang (e.g., 0.0075 inches), the self-biasing tabs (634') are configured to capture the proximal tip (680) with an extraction force of approximately 12 pounds. The wider opening and slightly tapered intermediate portion (684) allow the proximal tip (680) to be inserted between the self-biasing tabs (634') without triggering the needle retraction mechanism (e.g., a spring-release latch).

[0131] V. Exemplary Dual-Chamber Injection System Figures 67A to 77 show dual-chamber injection systems (3600) having a fluid transfer assembly (3650) according to several embodiments. The fluid transfer assembly (3650) is similar to the needle assembly (650) described herein in that it has one or more channels (3662) and a proximal tip (3680) similar to the corresponding channels (662) and proximal tip (3680) in the needle assembly (650) described herein. The dual-chamber injection system (3600) includes a needle connector (3610) formed at the distal end of a syringe body (3620) and a plunger member (3630) coupled to a proximal stopper member (3640) located inside the syringe body (3620). The distal stopper member (3690) is also located inside the syringe body (3620). Although not shown herein, the dual-chamber injection system (3600) may include a needle retraction system. The needle retraction system is located almost entirely inside the plunger member (3630).

[0132] Figures 68A and 68B show fluid transfer assemblies (3650) according to several embodiments. Figure 68B is an exploded view of the fluid transfer assembly (3650) shown in Figure 68A. The fluid transfer assembly (3650) includes a proximal portion (3660) configured to be partially positioned within the proximal end of an intermediate connector (3670). The fluid transfer assembly (3650) also includes a distal connector (3700) configured to receive the distal end of the intermediate connector, the intermediate connector similarly configured to be partially positioned within the proximal end of the distal connector (3700). The intermediate connector (3670) includes a radially extending annular flange (3674) configured to interfere with a distal stopper member (3690).

[0133] Figures 69A to 71D show the proximal portion (3660) and various components of a fluid transfer assembly (3650) according to several embodiments. The proximal portion (3660) of the fluid transfer assembly (3650) includes a proximal tip (3680), a longitudinal channel (3662), and a radially extending annular flange (3674). The proximal tip (3680) in the fluid transfer assembly (3650) is similar to the proximal tip (680) in the needle assembly (650) described herein. In particular, the proximal tip (3680) includes a pyramidal proximal puncture tip (3682), a slightly tapered intermediate section (684), and a toroidal distal flange (686) (see Figure 71A), which are structurally and functionally similar to the pyramidal proximal puncture tip (682), slightly tapered intermediate section (684), and toroidal distal flange (686) of the proximal tip (680). As in the proximal tip (680), the transition between the pyramidal proximal puncture tip (3682) and the intermediate section (3684) within the proximal tip (3680) is smoothed. Therefore, the proximal tip (3680) is configured to minimize snagging or sticking of the funnel (3696) as it passes through the distal stopper member (3690) of the proximal tip (3680) (see Figures 75A to 77).

[0134] As shown in Figure 71B, the longitudinal channel (3662) in the proximal portion (3660) of the fluid transfer assembly (3650) has a rounded / circular cross-section, thereby minimizing fluid flow constraints through the longitudinal channel (3662).

[0135] As shown in Figures 71C and 71D, the radially extending annular flange (3674) is configured to temporarily interfere with a pair of tabs (3698) in the stopper insert (3694) to hold the distal stopper member (3690) and the fluid transfer assembly (3650) in the transfer configuration (see Figures 75A to 77) relative to each other when a sufficient force is applied to the plunger member (3630) to transfer the fluid through the longitudinal channel (3662) in the fluid transfer assembly (3650). The pair of tabs (3698) are also configured to allow the radially extending annular flange (3674) to pass through when an additional force is applied to the plunger member (3630) after the transfer of fluid across the longitudinal channel (3662) is complete. The longitudinal channel (3662) is configured such that the fluid flow is stopped after the annular flange (3674) has moved proximal to the tabs (3698).

[0136] Figures 72A to 74B show distal connectors (3700) according to various embodiments. The distal connector (3700) includes a radially enlarged proximal portion (3710) and a distal portion (3720). The radially enlarged proximal portion (3710) is configured to receive the distal end of the intermediate connector (3670) of the fluid transfer assembly (3650). As shown in Figure 73C, the opening (3712) in the proximal portion (3710) has a squircle cross-sectional shape. Therefore, when the intermediate connector (3670), which is tubular with a circular cross-sectional shape, is inserted into the opening (3712) in the proximal portion (3710) (see Figure 74A), a mechanical fit is formed between the distal end of the intermediate connector (3670) and the proximal portion (3710) of the distal connector (3700).

[0137] As shown in Figures 73B and 74B, the distal portion (3720) is configured to fit into the distal opening of the syringe body (3620) and to connect the fluid transfer assembly (3650) to it. The outer surface of the distal portion (3720) has a rounded triangular cross-section. Thus, when the distal connector (3700) is inserted into the opening (3622) in the distal end of the syringe body (3620) (see Figure 74A), a mechanical fit is formed between the distal portion (3720) of the distal connector (3700) and the distal end of the syringe body (3620). Figure 74B also shows that three channels (3730) are formed between the outer surface of the distal portion (3720) of the distal connector (3700) and the distal end of the syringe body (3620). These channels (3730) allow fluid to exit from inside the syringe body (3620) to outside the syringe body (3620).

[0138] Figures 75A to 76C show distal stopper members (3690) for use with dual-chamber injection systems according to several embodiments. The distal stopper member (3690) includes a readily available rubber stopper (3692) and an internally positioned stopper insert (3694). The stopper insert (3694) includes a pair of elastically deformable tabs (3698) (see Figures 76A to 76B) that form part of a distally facing funnel (3696). As described herein, the tab (3698) is configured to temporarily interfere with the radially extending annular flange (3674) of the fluid transfer assembly (3650) in order to hold the distal stopper member (3690) and the fluid transfer assembly (3650) in the transfer configuration (see Figure 77) when a sufficient amount of force is applied to the plunger member (3630) to transfer the fluid through the longitudinal channel (3662) in the fluid transfer assembly (3650). The tab (3698) is also configured to allow the radially extending annular flange (3674) to pass through it when an additional force is applied to the plunger member (3630) after the transfer of fluid across the longitudinal channel (3662) is complete.

[0139] Figure 77 illustrates various steps of fluid transfer and injection (4000) using a dual-chamber injection system such as the system (3600) described herein. In step (4010), the system is in a transport configuration in which the proximal tip (3680) is positioned opposite the distal surface of a rubber stopper (3692).

[0140] In step (4020), sufficient force is applied to the plunger assembly (3630) to drive the distal stopper member (3690) distal to the proximal tip (3680), causing the proximal tip (3680) to puncture the rubber stopper (3692). With the transfer tube assembly (3650) and the distal stopper member (3690) in the positions shown in step (4020), the system is in a fluid transfer configuration in which the proximal and distal chambers are fluid-coupled via a longitudinal channel (3662) in the needle assembly (3650). As described herein, interference between the tab (3698) of the stopper insert (3694) and the radially extending annular flange (3674) of the needle assembly (3650) maintains the fluid transfer configuration while the fluid is being transferred from the proximal chamber to the distal chamber by continuing to apply force to the plunger member (3630).

[0141] In step (4030), the proximal stopper member (3640) is moved distally until it comes into contact with the distal stopper member (3690) and the fluid transfer is completed. At this point, since the fluid transfer has been stopped, an increased force may be applied to the distal stopper member (3690).

[0142] In step (4040), the increased force applied to the distal stopper member (3690) overcomes interference between the tab (3698) of the stopper insert (3694) and the radially extending annular flange (3674) of the needle assembly (3650), moving the distal stopper member (3690) distal to the fluid transfer member (3650) and discharging the fluid from the distal chamber to the outside of the syringe body (3620).

[0143] In step (4050), the fluid is discharged from the distal chamber to the outside of the syringe body (3620). The distal stopper member (3690) moves toward the distal end of the syringe body (4020).

[0144] VI. Exemplary Continuous Safety Injection System Figures 78A to 85 show continuous safety injection systems (4200, 4400) having needle assemblies (4650, 4750) according to several embodiments. The needle assemblies (4650, 4750) are similar to the needle assembly (650) described herein in that they have one or more channels (4662) and a proximal tip (4680) similar to the corresponding channels (662) and proximal tip (4680) in the needle assembly (650) described herein. The continuous safety injection systems (4200, 4400) include a needle hub assembly (4610) coupled to a syringe body (4620) and a plunger member (4630) coupled to a proximal stopper member (4640) located inside the syringe body (4620). A distal stopper member (4690) is also located inside the syringe body (4620). The continuous safety injection system (4600) also includes a needle retraction system. The needle retraction system is located almost entirely inside the plunger member (4630).

[0145] Figure 79 shows a continuous safety injection system (4200) according to several embodiments. The continuous safety injection system (4200) includes a needle assembly (4650) having a proximal portion (4660) and a distal portion (4654), each configured to be partially positioned within the respective proximal and distal ends of an intermediate connector (4670). The needle assembly (4650) is similar to the needle assembly (650) described herein in that it has one or more channels and a proximal tip similar to the corresponding channels (662) and proximal tip (680) in the needle assembly (650) described herein. The intermediate connector (4670) includes an annular recess (4672) configured to interfere with a needle latch to prevent the needle assembly (4650) from being retracted proximal before the injection is completed. The intermediate connector (4670) also includes an exhaust opening (4676) for releasing pressure buildup during injection.

[0146] Figure 80 shows various steps of a continuous injection (4300) using a dual-chamber injection system such as the system (4200) described herein. In step (4310), the system is in a transport configuration in which the proximal tip of the needle assembly is positioned opposite the distal surface of the rubber stopper of the distal stopper member (4290).

[0147] In step (4320), sufficient force is applied to the plunger assembly to drive the distal stopper member (4290) distally relative to the proximal tip, so that the proximal tip punctures the rubber stopper. The distal movement of the distal stopper member (4290) causes the fluid to be discharged from the distal chamber through the longitudinal channel in the needle assembly (4650).

[0148] In step (4030), the distal stopper member (4290) moves distally to the distal end of the syringe body (4620) until fluid transfer from the distal chamber is complete. Fluid transfer from the distal chamber is also stopped because the longitudinal channel is no longer fluidly connected to the distal chamber. Instead, the movement of the distal stopper member (4290) fluidly connects the longitudinal channel to the proximal chamber.

[0149] In step (4040), the proximal stopper member (4240) is moved distally to contact the distal stopper member (4290) and thereby complete the transfer of fluid from the proximal chamber. Thus, the system (4200) is used to inject fluid sequentially, first from the distal chamber and then from the proximal chamber. After the injection of fluid from both the distal and proximal chambers, the needle retraction system applies a proximal force to the needle assembly (4650), allowing it to be pulled at least partially into the needle hub assembly (4610) and / or syringe body (4620), so that the sharp distal tip of the needle assembly (4650) is positioned inside the needle hub assembly (4610) and / or syringe body (4620), thereby preventing accidental needle stick injuries.

[0150] Figures 81 and 82 show dual-chamber safety injection systems (4400) according to several embodiments. The difference between the safety injection systems (4400) shown in Figures 81 and 82 and the continuous safety injection systems (4200) shown in Figures 79 and 80 is that the safety injection system (4200) includes a distal slot (4676) within the intermediate connector (4670), while the safety injection system (4400) does not include a distal slot within the intermediate connector (4670). No fluid drug / injectable is stored in the distal chamber of the dual-chamber safety injection system (4400). The sequence of steps (4510) to (4540) shown in Figure 82 (4500) is designed to minimize interaction between the stainless steel components of the needle assembly (4650) and the drug stored in the proximal chamber of the dual-chamber safety injection system (4400) during long-term storage of the filled dual-chamber continuous safety injection system (4400). The drug and stainless steel components come into contact only momentarily during injection. The dual-chamber safety injection system (4400) may include only a polymer latch mechanism to further minimize interaction between the injectable drug and the metal. Steps (4510) to (4540) shown in Figure 82 are substantially identical to steps (4310) to (4340) shown in Figure 80, except that no fluid drug / injectable drug is stored in the distal chamber of the dual-chamber safety injection system (4400). Therefore, steps (4520) and (4530) introduce only the needle assembly (4650) into the proximal chamber to inject the fluid inside (immediately after the introduction of the needle assembly (4650)).

[0151] Figures 83A to 85 show various components of a needle assembly (4550) for use with a continuous safety injection system (e.g., the systems described herein (4200, 4400)) according to several embodiments. The difference between the needle assembly (4550) shown in Figures 83A to 85 and the needle assembly (4650) shown in Figures 78A to 82 is that the needle assembly (4550) includes two longitudinally separated longitudinal channels (4562A, 4562B) (see Figures 83B and 84) instead of a single longitudinal channel.

[0152] Figure 83A shows a needle assembly (4550) for use with a safety continuous injection system according to several embodiments. The needle assembly (4550) comprises a proximal portion (4560) and a distal portion (4554), each configured to be partially positioned within the respective proximal and distal ends of an intermediate connector (4570). The needle assembly (4550) is similar to the needle assembly (650) described herein in that it has one or more channels and a proximal tip similar to the corresponding channels (662) and proximal tip (680) in the needle assembly (650) described herein. The intermediate connector (4570) includes an annular recess (4572) configured to interfere with a needle latch to prevent the needle assembly (4550) from being retracted proximal before the injection is completed.

[0153] Figure 83B shows the proximal portion (4560) of a needle assembly (4550) according to several embodiments. The proximal portion (4560) has a distal longitudinal channel (4562A) and a proximal longitudinal channel (4562B). The proximal portion (4560) also has a proximal tip (4580) similar to the proximal tip (680) described herein. Figure 84 shows the proximal portion (4560) in more detail, showing the proximal longitudinal channel (4562B). The distal longitudinal channel (4562A) is configured to provide an exit from the distal chamber to the outside of the syringe body (4520). The proximal longitudinal channel (4562B) is configured to provide an exit from the proximal chamber to the outside of the syringe body (4520).

[0154] Figure 85 illustrates various steps of a continuous injection (4800) using a dual-chamber injection system having the needle assembly (4550) described herein. In step (4810), the system is in a transport configuration in which the proximal tip (4580) of the needle assembly (4550) is positioned opposite the distal surface of the rubber stopper of the distal stopper member (4690).

[0155] In step (4820), sufficient force is applied to the plunger assembly (4630) to drive the distal stopper member (4690) distally relative to the proximal tip (4580), so that the proximal tip (4580) punctures the rubber stopper. The distal movement of the distal stopper member (4690) causes the fluid to be discharged from the distal chamber through the distal longitudinal channel (4562A) in the needle assembly (4550).

[0156] In step (4830), the distal stopper member (4690) moves distally to the distal end of the syringe body (4620) until fluid transfer from the distal chamber is complete. Fluid transfer from the distal chamber is also stopped because the proximal longitudinal channel (4562B) is fluid-connected to the proximal chamber. At this point, fluid transfer from the proximal chamber can be started via the proximal longitudinal channel (4562B).

[0157] In step (4040), the proximal stopper member (4840) contacts the distal stopper member (4690) and is moved distally until fluid transfer from the proximal chamber through the proximal longitudinal channel (4562B) is complete. Thus, the system is used to inject fluid sequentially, first from the distal chamber and then from the proximal chamber. After the injection of fluid from both the distal and proximal chambers, the needle retraction system applies a proximal force to the needle assembly (4550), allowing it to be pulled at least partially into the needle hub assembly (4610) and / or syringe body (4620), so that the sharp distal tip of the needle assembly (4550) is positioned inside the needle hub assembly (4610) and / or syringe body (4620), preventing accidental needle stick injuries.

[0158] VII. Exemplary injection system with valve Figures 86 to 91 show injection systems (4900) having a flow regulator (4950) according to several embodiments. Figure 86 shows an injection system (4900) which is a dual-chamber injection system having a flow regulator (4950). The injection system (4900) includes a tube (4910) coupled to a syringe body (4920) and a plunger member (4930) coupled to a proximal stopper member (4940) located inside the syringe body (4920). The needle hub assembly (4910) also includes a distal stopper member (4990) located inside the syringe body (4920). The proximal and distal stopper members (4940, 4990) define a proximal chamber (4942). The distal stopper member (4990) and the distal end of the syringe body (4920) define the distal chamber (4992). The proximal and distal chambers (4942, 4992) can contain liquids and / or lyophilized powders that are configured to be mixed before injection.

[0159] While using a dual-chamber injection system to mix drug components, pressure may build up in the distal chamber, which could unintentionally / prematurely discharge some of the drug components from the distal chamber in the existing system. The flow regulator (4950) in the injection system (4900) described herein minimizes and / or prevents unintentional / premature injection of drug components from the distal chamber (4992) during mixing, and unintentional movement of drug components from the distal chamber through the distal opening during shipping.

[0160] Figure 88 shows in more detail a flow regulator (4950) installed within an injection system (4900) according to several embodiments. The flow regulator (4950) includes a housing (4952) that defines a harpoon mount (4954) configured to be coupled (e.g., via a mechanical fit) to the distal end of a transfer tube (4910). The housing (4952) also defines a liquid port (4956) configured to provide an outlet from the distal chamber (4992) to the outside of the syringe body (4920). The flow regulator (4950) also includes an elastic seal (4958). The housing (4952) also defines a compliant pin (4960) configured to bite into the inner diameter of the distal opening (4922) of the syringe body (4920). The compliant pin (4960) is hollow between the liquid ports (4956) to provide a selectively open flow path through the compliant pin (4960) out of the distal opening (4920).

[0161] Figures 88 and 89 are detailed longitudinal cross-sectional views of a flow regulator (4950) installed within an injection system (4900), showing the components of the flow regulator (4950) in a closed configuration (Figure 88) and an open configuration (Figure 89). The elastic seal (4958) within the flow regulator (4950) is configured and / or biased to remain closed at a pressure lower than a predetermined pressure (e.g., 5 psi) in the distal chamber (4992). A pressure higher than the predetermined pressure in the distal chamber (4992) pushes the elastic seal (4958) open.

[0162] Figure 88 shows the flow regulator (4950) in a closed configuration. The low pressure in the distal chamber (4992) biases the elastic seal (4958) to close the liquid port (4956) defined by the housing (4952) (see paths A and B). Furthermore, the elastic seal (4958) provides a fluid-tight seal between the housing (4952) and the distal end of the syringe body (4920) (see path C). Thus, the flow regulator (4950) being installed in the distal chamber (4992) and under its low pressure closes all possible passages (A, B, and C) to prevent accidental / premature discharge of drug components from the distal chamber (4992).

[0163] Figure 89 shows the flow regulator (4950) in an open configuration. Due to the higher pressure in the distal chamber (4992) (e.g., during injection), the elastic seal (4958) is pushed away from the liquid port (4956) defined by the housing (4952), opening pathways A and B. However, the elastic seal (4958) continues to provide a fluid-tight seal between the housing (4952) and the distal end of the syringe body (4920) (see pathway C). Thus, the flow regulator (4950) is installed in the distal chamber (4992) and, under its high pressure, opens two of the three pathways (A and B), allowing the mixed drug to be discharged from the distal chamber (4992).

[0164] Figures 90 and 91 show the end of an injection using the dual-chamber injection system (4900) described herein. When the injection of the mixed drug from the distal chamber (4992) is complete, the distal stopper member (4990) is at the distal end of the syringe body (4920). The complementary conical shape of the guide 4994 of the distal stopper member (4990) and the flow regulator (4950) minimizes the space lost when the flow regulator (4950) is added to the system (4900). The flow regulator (4950) described herein minimizes and / or prevents unintentional / premature injection of drug components from the distal chamber (4992).

[0165] VIII. Exemplary pre-filled dual-chamber continuous safety injection system and method Figures 92–94 are longitudinal side views and two progressively detailed longitudinal cross-sectional views showing a pre-filled dual-chamber continuous safety injection system (100''') according to several embodiments. The pre-filled dual-chamber continuous safety injection system (100''') includes a conventional readily available pre-filled syringe body (34) in which conventional readily available proximal and distal stopper members (32, 36) are disposed. The proximal and distal stopper members (32, 36), together with the syringe body (34), define the proximal and distal chambers (40, 42). A first fluid and a second fluid (252, 254) are contained in the distal and proximal chambers (42, 40), respectively. The proximal and distal stopper members (32, 36) close the proximal and distal ends of the proximal chamber (40). The distal stopper member (36) closes the proximal end of the distal chamber (42). In some embodiments, the distal surface of the proximal stopper member (32) and the proximal surface of the distal stopper member (36) are each coated with a lubricating polymer coating (e.g., PTFE or ETFE), and the first and second polymer coatings of the proximal and distal stopper members (32, 36), together with the syringe body (34), define the proximal chamber (40). The lubricating polymer coating also serves to isolate the rubber of the proximal and distal stopper members (32, 36) from the second liquid (254). The proximal stopper member and the distal stopper member (32, 36) may be oriented as shown in Figures 92 to 94, or the distal stopper (36) may be inverted so that the lubricating coating faces the distal chamber (42) so that the first liquid (252) in the distal chamber (42) comes into contact with the lubricating coating for storage.

[0166] A needle hub assembly (606') is positioned at the distal end of the distal chamber (42). The needle hub assembly (606') includes a needle hub (608) and a needle assembly ("needle") (76'') detachably coupled thereto. In some embodiments, a needle cover member (not shown) may be placed on the needle hub assembly (606') for storage. The pre-filled dual-chamber continuous safety injection system (100'') facilitates the continuous injection of a first fluid (252) from the distal chamber (42) and then a second fluid (254) from the proximal chamber (40) when the plunger assembly (44) is continuously inserted into the syringe body (34) to varying degrees by the user. The plunger assembly (44) includes a plunger housing member (69) coupled to a proximal stopper member (32) and a plunger operating interface (128). The first and second liquids (252, 254) located in the distal and proximal chambers (42, 40), respectively, may be any liquid or gel, such as an aqueous or oily drug solution.

[0167] The pre-filled dual-chamber continuous safety injection system (100'') has a crimped needle configuration in which, when presented to the user, the needle hub assembly (606') is mounted in a ready-to-inject position after removing a needle cover member (not shown) which may include elastic sealing material on its inner surface to interface with the distal needle member (78) and / or distal hub (608) during storage. Although the crimped needle is shown mounted in a fixed position, the crimped needle can be detachably coupled to the syringe body (34) (e.g., using a Luer slip or Luer lock interface (not shown)), and the proximal member (50, see Figures 93 and 94) of the needle assembly (76'') extends into the distal chamber (42) through the Luer interface. Alternatively, the needle may be fixedly or detachably mounted to a flange on the cartridge body instead of the syringe.

[0168] The needle assembly (76'') includes a proximal needle member (50, see Figures 93 and 94) and a distal needle member (78, not shown in Figures 93 and 93, see Figure 92), which are coupled to opposing ends (i.e., the respective proximal and distal ends) of a needle connector member (83, see Figures 94 and 94). The needle connector member (83') is a tubular member coupled to the distal needle member (78), which also defines a sharp distal end (81) having a distal opening (82). The needle assembly (76'') defines a proximal longitudinal channel (85') and an intermediate opening (80'). The intermediate opening (80') is located adjacent to the distal end of the syringe body (34). The proximal longitudinal channel (85') is defined by the proximal needle member (50''). In some embodiments, the needle proximal member (50'') is a solid proximal end feature.

[0169] As shown in Figure 94, the proximal member distal anchor (87) of the needle proximal member (50'') is located inside the proximal end of the tubular needle joint member (83'). In some embodiments, the needle proximal member (50'') is coupled to the proximal end (89) of the tubular needle joint member (83') by an interference fit between the proximal member distal anchor (87) and the proximal end (89) of the tubular needle joint member (83'). In other embodiments, the proximal end (89) of the tubular needle joint member (83') is welded to the needle proximal member (50''). In some embodiments, the weld is an "overlap" weld from the needle joint member (83') to the needle proximal member (50'''). The cross-section of the needle proximal member (50'') in the weld can be rectangular, crescent-shaped, or dumbbell-shaped, resulting in the components being fastened together, but allowing the fluid to flow through the inside of the needle joint member (83'') across the joint.

[0170] In some embodiments, the needle proximal member (50'') is formed by stamping a flat piece of sheet metal or metal wire to form various feature parts of the needle proximal member (50''). Forming the needle proximal member (50'') by stamping reduces manufacturing complexity and cost. The outer diameters of the needle proximal member (50'') and the needle joint member (83'') are substantially small, facilitating the retraction of the needle assembly (76'') while minimizing snagging of the proximal and distal stopper members (32, 36).

[0171] In short, additional components of the pre-filled dual-chamber continuous safety injection system (100''') include a retraction system inside the plunger member (44), a needle retention feature, an energy storage member (e.g., a spring), and an energy storage member latch. In the embodiments shown in Figures 92 to 97, a substantial portion of the safety needle retraction hardware resides within the plunger housing (69). Additional components also include a needle holder member (e.g., an O-ring, a needle latch, and / or a detent) inside the needle hub (608). Additional components further include a funnel within the distal stopper member (36) for guiding the proximal needle member (50'') to the center of the distal stopper member (36).

[0172] Figures 92 to 97 illustrate safe continuous injection methods using the pre-filled dual-chamber continuous safety injection system (100''') described herein, according to several embodiments.

[0173] Figures 92–94 show a pre-filled dual-chamber continuous safety injection system (100''') in a first / ready-to-use configuration. The only difference between the first / ready-to-use configuration and the factory configuration (not shown) is that a needle cover member (not shown) present in the factory configuration is removed in the first / ready-to-use configuration. In the first / ready-to-use configuration, the proximal longitudinal channel (85') is located within the distal chamber (42) together with the intermediate opening (80'). Therefore, there is no flow path between the proximal chamber (40) and the distal opening (82). Thus, any distal force applied to the plunger operating interface (128) is transferred through the plunger member (44), the proximal stopper member (32), and the incompressible second fluid (254) in the proximal chamber (40) to move the distal stopper member (36) distal to the syringe body (34). As the distal stopper member (36) moves distally relative to the syringe body (34), the pressure inside the distal chamber (42) increases, which drives the first liquid (252) out of the distal chamber (42) through the intermediate opening (80'), the tubular needle connector member (83'), and the distal needle member (78), and then out through the distal opening (82) of the distal needle member (78).

[0174] Figure 95 shows a filled dual-chamber continuous safety injection system (100'') after the distal stopper member (36) has been moved distally by a first distance relative to the syringe body (34). The distal chamber (42) has been partially crushed / reduced in size, and some of the first fluid (252) has been discharged from the filled dual-chamber continuous safety injection system (100'') through the distal opening (82). As the distal stopper member (36) is moved distally relative to the syringe body (34), the proximal needle member (50'') of the needle assembly (76'') also penetrates the distal stopper member (36). The proximal longitudinal channel (85') is still within the distal chamber (42) or is blocked by the distal stopper member (36). Therefore, there is no flow path between the proximal chamber (40) and the distal opening (82), and the distal force applied to the plunger operating interface (128) is still transmitted to the distal stopper member (36) as described above.

[0175] Figure 96 shows the filled dual-chamber continuous safety injection system (100'') after the distal stopper member (36) has been moved a second distance distal to the syringe body (34) (further than the first distance shown in Figure 95). The distal chamber (42, see Figure 95) is almost completely crushed / almost completely ejected, and most of the first fluid (252, see Figure 95) has been discharged from the filled dual-chamber continuous safety injection system (100'') through the distal opening (82). Further distalization of the distal stopper member (36) relative to the syringe body (34) also causes the proximal needle member (50'') of the needle assembly (76'') to further penetrate the distal stopper member (36). Further penetration of the proximal needle member (50'') of the needle assembly (76'') causes the proximal longitudinal channel (85') to be located within the proximal chamber (40) at this point. Therefore, at this point, a flow path exists between the proximal chamber (40) and the distal opening (82), and the distal force applied to the plunger operating interface (128) moves the proximal stopper member (32) distally relative to the syringe body (34) and the distal stopper member (36), causing the second liquid (254) to be discharged from the proximal chamber (40). The opening of the flow path between the proximal chamber (40) and the distal opening (82) creates a second configuration of the filled dual-chamber continuous safety injection system (100''') that allows the second liquid (254) to be discharged from the proximal chamber (40) after the first liquid (252) has been almost completely discharged from the distal chamber (42).

[0176] Figure 96 also shows the filled dual-chamber continuous safety injection system (100''') after the proximal stopper member (32) has been moved a first distance distal to the syringe body (34), and the filled dual-chamber continuous safety injection system (100''') is in a second configuration. The proximal chamber (40) has been partially crushed / reduced in size, and some of the second fluid (254) has been discharged from the filled dual-chamber continuous safety injection system (100''') through the distal opening (82). As shown in Figure 100, the proximal longitudinal channel (85') is located within the proximal chamber (40), so at this point, a flow path exists between the proximal chamber (40) and the distal opening (82). The flow path between the proximal chamber (40) and the distal opening (82) allows the proximal stopper member (32) to move distally toward the distal stopper member (36) by discharging a portion of the second fluid (254) through the proximal longitudinal channel (85'). The distal force applied to the plunger operating interface (128) is transmitted to move the proximal stopper member (32), so the distal stopper member (36) is substantially stopped moving at this point.

[0177] Figure 97 shows a filled dual-chamber continuous safety injection system (100''') after the second fluid (254, see Figure 96) has been substantially discharged from the proximal chamber (40, see Figure 96) by the proximal stopper member (32) continuing to move distally, and the filled dual-chamber continuous safety injection system (100''') is in a second configuration. The proximal needle member (50'') of the needle assembly (76'') is moved further proximal relative to the plunger assembly (44), which activates the energy storage member latch and releases the energy storage member (spring), causing the spring to pull / retract the needle assembly (76'') at least partially toward the plunger assembly (44), positioning the sharp distal end (81) of the distal needle member (78) of the needle assembly (76'') inside the syringe body (34). The retraction of the needle assembly (76'') brings the pre-filled dual-chamber continuous safety injection system (100''') into a safe configuration for disposal after injection.

[0178] Exemplary needle assembly Figures 98 to 103B show needle assemblies (76'') for use with a pre-filled dual-chamber continuous safety injection system (100'''') according to several embodiments.

[0179] Figure 98 shows a needle hub assembly (606') with a rigid needle shield (612) attached, according to several embodiments. Figure 98 also shows the needle proximal member (50'') and needle bonding member (83') of the needle assembly (76'').

[0180] Figure 99 shows needle assemblies (76'') according to several embodiments. The needle assembly (76'') includes a needle proximal member (50'') and a needle distal member (78), each configured to be partially positioned within the respective proximal and distal ends of a needle connector member (83'). The needle proximal member (50'') includes a proximal tip (84) at its proximal end, configured to be captured for retraction of the needle assembly (76'') after injection. The distal end of the needle distal member (78) includes a sharp distal end (81) configured to puncture target tissue for injection. The sharp distal end (81) defines a distal opening (82) for injection. The needle connector member (83') includes an annular recess (72) configured to interfere with a needle latch to prevent the needle assembly (76'') from being retracted proximally before the injection is completed.

[0181] Figure 100 shows the proximal tip (84) of the needle proximal member (50'') in more detail. The proximal tip (84) includes a faceted proximal puncture tip (86). The faceted proximal puncture tip (86) facilitates puncture of the proximal stopper member and the distal stopper members (32, 36). The needle proximal member (50'') of the needle assembly (76'') also includes a diameter-reducing portion (88) immediately distal to the proximal tip (84). The diameter-reducing portion (88) increases the probability and safety of the proximal tip (84) of the needle proximal member (50'') being captured and enabling the retraction of the needle assembly (76'').

[0182] Figure 101 shows a needle proximal member (50'') according to several embodiments. The needle proximal member (50'') includes a proximal tip (84) at its proximal end, a proximal longitudinal channel (85') between its proximal and distal ends, and two distal longitudinal channels (90) extending from its distal end.

[0183] Figure 102 is a longitudinal cross-sectional view of the needle proximal member (50''). The needle proximal member (50'') includes two distal longitudinal channels (90) formed within substantially opposing surfaces of the needle proximal member (50''). As shown in Figure 99, when the needle proximal member (50'') is partially positioned within the needle joint member (83'), the distal longitudinal channels (90) form two channels that enter the needle joint member (83') from the outside of the needle assembly (76'') and then enter the needle distal member (78) and exit from the sharp distal end (81) of the needle distal member (78).

[0184] Figure 99 shows the fully assembled needle assembly (76'') by inserting the distal end of the needle proximal member (50'') into the needle joint member (83'') until only the proximal end of the distal longitudinal channel (90) remains outside the needle joint member (83''). This proximal end of the distal longitudinal channel (90) forms an intermediate opening (80') within the needle assembly (76'') that fluidly couples the inside and outside of the needle assembly (76'').

[0185] Figures 103A and 103B show axial cross-sections of the distal ends of the needle proximal members (50'', 50B) according to several embodiments. The distal end of the needle proximal member (50'') shown in Figure 103A has a dumbbell-shaped cross-section similar to that of the needle proximal member (50'') shown in Figures 101 and 16. The distal end of the needle proximal member (50B) shown in Figure 103B has a crescent-shaped cross-section. The dumbbell and crescent shapes define two and one distal longitudinal channels (90, 90B), respectively. The distal longitudinal channels (90, 90B) have rounded / circular cross-sections, which minimize fluid flow constraints through the distal longitudinal channels (90, 90B). The circular cross-section is efficient for fluid flow because it minimizes fluid interaction with the channel walls, which would otherwise impose a zero-velocity boundary condition on the flowing fluid. Therefore, by minimizing wall exposure, the amount of shear resistance the fluid experiences during flow is minimized. Hagen-Poiseuil equation:

[0186] According to TIFF2026065007000003.tif13170, the resistance of the logic pipe is R 4 Because it is inversely proportional to the (radius of the cross-sectional area), even if the cross-sectional area is maintained, the fluid flow resistance of a single round channel (90B) (see Figure 103B) can be lower than that of a double channel (90) (see Figure 103A).

[0187] Even with the formation of a distal longitudinal channel (90, 90B) internally, the needle proximal member (50'', 50B) has a bending moment of inertia sufficient to improve its stiffness and resistance to bending. In fact, the needle proximal member (50'', 50B) is similar to a steel I-beam and has similar stiffness properties. Resistance to bending is particularly important when the needle proximal member (50'', 50B) drills the stopper member 640. Minimizing bending when the needle proximal member (50'', 50B) drills the stopper member 640 increases the probability that the proximal tip (84) of the needle proximal member (50'') will be captured and the needle assembly (76'') will be retracted.

[0188] The diameter of the needle proximal member (50'', 50B) is also relatively large (e.g., about 0.026 inches compared to a cold-formed proximal member having a diameter of about 0.020 inches). As a result of the larger diameter of the needle proximal member (50''), the overall bending moment of inertia is higher, the resistance to bending is greater, and this also improves the probability of capture. The needle proximal member (50'', 50B) is also very close in diameter to the needle joint member (83'), which may have a diameter of about 0.036 inches. Due to the similar diameters, the needle assembly (76'') is more easily retracted through the stopper member during retraction, as the needle joint member (83') is less likely to get caught in the stopper member during retraction, resulting from the relatively small diameter difference between the needle joint member (83') and the needle proximal member (50'').

[0189] IX. Exemplary pre-filled needleless dual-chamber continuous injection system and method Figures 104-106 are longitudinal cross-sectional views and two progressively detailed longitudinal cross-sectional views showing a pre-filled needleless dual-chamber continuous injection system (1800) according to several embodiments. The pre-filled needleless dual-chamber continuous safety injection system (1800) is similar to the pre-filled dual-chamber continuous injection system (100) shown in Figures 92-94. There are two main differences between the systems (1800, 100). First, the dual-chamber continuous injection system (1800) shown in Figures 104-106 does not include a “needle” that extends outside the syringe body (1834), such as the distal needle member (78) in the dual-chamber continuous injection system (100) shown in Figures 92-94. Second, the dual-chamber continuous injection system (1800) shown in Figures 104-106 does not include a needle retraction system, such as that found in the dual-chamber continuous injection system (100) shown in Figures 92-94. Therefore, the dual-chamber continuous injection system (1800) is not a "safe" injection system.

[0190] The pre-filled needleless dual-chamber continuous injection system (1800) includes a conventional, readily available pre-filled syringe body (1834) with conventional, readily available proximal and distal stopper members (1832, 1836) housed inside. The proximal and distal stopper members (1832, 1836), together with the syringe body (1834), define the proximal and distal chambers (1840, 1842). The first and second fluids (1852, 1854) are housed in the distal and proximal chambers (1842, 1840), respectively. The proximal and distal stopper members (1832, 1836) occlude the proximal and distal ends of the proximal chamber (1840). The distal stopper member (1836) closes the proximal end of the distal chamber (1842). In some embodiments, the distal surface of the proximal stopper member (1832) and the proximal surface of the distal stopper member (1836) are each coated with a lubricating polymer coating (e.g., PTFE or ETFE), and the first and second polymer coatings of the proximal and distal stopper members (1832, 1836), together with the syringe body (1834), define the proximal chamber (1840). The lubricating polymer coating also serves to isolate the rubber of the proximal and distal stopper members (1832, 1836) from the second liquid (1854). The proximal stopper member and the distal stopper member (1832, 1836) may be oriented as shown in Figures 104 to 106, or the distal stopper (1836) may be inverted so that the lubricating coating faces the distal chamber (1842) so that the first liquid (1852) in the distal chamber (1842) comes into contact with the lubricating coating for storage.

[0191] The dual-chamber continuous injection system (1800) shown in Figures 104-106 does not include a “needle” extending outside the syringe body (1834). Instead, the dual-chamber continuous injection system (1800) includes a fluid transfer assembly (1876). The fluid transfer assembly (1876) of the pre-filled needleless dual-chamber continuous injection system (1800) facilitates the continuous injection of a first fluid (1852) from the distal chamber (1842) and then the injection of a second fluid (1854) from the proximal chamber (1840) when the plunger assembly (1844) is continuously inserted into the syringe body (1834) to varying degrees by the user. The plunger assembly (1844) includes a plunger housing member (1869) coupled to a proximal stopper member (1832) and a plunger operating interface (1828). The first and second liquids (1852, 1854) located in the distal and proximal chambers (1842, 1840), respectively, may be any liquid or gel, such as an aqueous or oily drug solution.

[0192] The fluid transfer assembly (1876) of the pre-filled needleless dual-chamber continuous injection system (1800) is configured for use with a connector (e.g., a Luer lock or Luer slip interface coupled to a needle or fluid transfer tube (not shown) having a sharpened end).

[0193] The fluid transfer assembly (1876) includes a fluid transfer proximal member (1850, see FIGS. 105 and 106) coupled to the proximal end of a fluid transfer joint member (1883, see FIGS. 105 and 106). The fluid transfer proximal member (1850) is a metal spike with a proximal channel (1885) formed therein. The fluid transfer joint member (1883) is configured to be coupled to the distal end of the fluid transfer proximal member (1850) and to secure the fluid transfer assembly (1876) within the distal opening of the syringe body (1834). The fluid transfer joint member (1883) includes a fluid transfer distal anchor (1891), and the fluid transfer distal anchor (1891) includes an open core (1892) to provide a fit for the fluid transfer distal anchor (1891). The fluid transfer joint member (1883) may be coupled to the fluid transfer proximal member (1850) by mechanical fitting. The fluid transfer joint member (1883) can secure the fluid transfer assembly (1876) to the syringe body (1834) by mechanical fitting between the fluid transfer distal anchor (1891) and the distal end of the syringe body (1834). The fluid transfer joint member (1883) can define one or more channels therein to provide an intermediate opening (1880) between the inside and outside of the syringe body (1834) / distal chamber (42). The intermediate opening (1880) is disposed adjacent to the distal end of the syringe body (1834). The proximal longitudinal channel (1885) is defined by the proximal fluid transfer member (1850). In some embodiments, the fluid transfer proximal member (1850) is a solid proximal end feature.

[0194] In some embodiments, the fluid transfer proximal member (1850) is formed by stamping a single piece of flat sheet metal or metal wire to form various features of the fluid transfer proximal member (1850). Forming the fluid transfer proximal member (1850) by stamping reduces manufacturing complexity and cost.

[0195] Figures 104-109 illustrate a safe continuous injection method using the filled needle-free dual-chamber continuous injection system (1800) described herein, according to several embodiments.

[0196] Figures 104-106 illustrate the filled needle-free dual-chamber continuous injection system (1800) in a first / ready-to-use configuration. The only difference between the first / ready-to-use configuration and the shipping configuration (not shown) is that a syringe body cap (not shown) present in the shipping configuration has been removed in the first / ready-to-use configuration.

[0197] In the first / ready-to-use configuration, the proximal longitudinal channel (1885) is disposed within the distal chamber (1842) along with the intermediate opening (1880). Thus, there is no flow path between the proximal chamber (1840) and the distal opening (1882). Thus, any distal-directed force applied to the plunger operation interface (1828) is transferred through the plunger member (1844), the proximal stopper member (1832), and the non-compressible second liquid (1854) within the proximal chamber (1840) to move the distal stopper member (1836) distally relative to the syringe body (1834). As the distal stopper member (1836) moves distally relative to the syringe body (1834), the pressure within the distal chamber (1842) increases, thereby driving the first liquid (1852) out of the distal chamber (1842) through the intermediate opening (1880) formed between the fluid transfer junction member (1883) and the distal end of the syringe body (1834) (e.g., to a luer connector).

[0198] Figures 107 and 108 show the filled needleless dual-chamber continuous injection system (1800) after the distal stopper member (1836) has been moved distally relative to the syringe body (1834) until the distal stopper member (1836) is almost in contact with the distal end of the syringe body (1836). The distal chamber (1842, see Figure 105) is almost completely crushed / almost completely ejected, and most of the first fluid (1852, see Figure 105) has been discharged from the filled needleless dual-chamber continuous injection system (1800) through the distal end of the syringe body (1836). The distal stopper member (1836) is also moved distally relative to the syringe body (1834), causing the fluid transfer proximal member (1850) of the fluid transfer assembly (1876) to penetrate the distal stopper member (1836). As the fluid transfer proximal member (1850) of the fluid transfer assembly (1876) penetrates, the proximal longitudinal channel (1885) is positioned within the proximal chamber (1840) at this point. Therefore, at this point, a flow path exists between the proximal chamber (1840) and the intermediate opening (1880), and the distal force applied to the plunger operating interface (1828) moves the proximal stopper member (1832) distally relative to the syringe body (1834) and the distal stopper member (1836), causing the second liquid (1854) to be discharged from the proximal chamber (1840). Opening the flow path between the proximal chamber (1840) and the distal opening (1882) results in a second configuration of the filled needleless dual-chamber continuous injection system (1800) that allows the second fluid (1854) to be discharged from the proximal chamber (1840) after the first fluid (1852) has been almost completely discharged from the distal chamber (1842).

[0199] Figure 109 shows a pre-filled needleless dual-chamber continuous injection system (1800) after the second fluid (1854, see Figure 107) has been substantially discharged from the proximal chamber (1840, see Figure 96) by the distal movement of the proximal stopper member (1832), and the pre-filled needleless dual-chamber continuous injection system (1800) is in a second configuration.

[0200] Exemplary fluid transfer assembly Figures 110–112C show fluid transfer assemblies (1876) for use with a pre-filled needleless dual-chamber continuous injection system (1800) according to several embodiments.

[0201] Figures 110 and 111 are perspective and exploded views of a fluid transfer assembly (1876) according to several embodiments. The fluid transfer assembly (1876) includes a fluid transfer proximal member (1850) configured to be partially positioned and coupled within the proximal end of a fluid transfer coupling member (1883). The fluid transfer proximal member (1850) includes a proximal puncture tip (1884) at its proximal end, configured to puncture a distal stopper member (1836). The fluid transfer coupling member (1883) includes a fluid transfer distal anchor (1891) configured to secure the fluid transfer assembly (1876) to the distal opening of the syringe body (1834) by an interference fit.

[0202] Figures 112A to 112C are perspective views, longitudinal sections, and axial sections of a fluid transfer proximal member (1850) according to several embodiments. The fluid transfer proximal member (1850) includes a proximal puncture tip (1884) at its proximal end and a proximal longitudinal channel (1885) between its proximal and distal ends.

[0203] The diameter of the fluid transfer proximal member (1850) is also relatively large (for example, about 0.026 inches to about 0.040 inches compared to a cold-formed proximal member with a diameter of about 0.020 inches). As a result of the larger diameter of the fluid transfer proximal member (1850), the overall bending moment of inertia is higher, and the resistance to bending is greater, which also improves the probability of capture. Due to its relatively large diameter and solid structure, the fluid transfer proximal member (1850) has a bending moment of inertia sufficient to improve stiffness and resistance. Resistance to bending is particularly important when the fluid transfer proximal member (1850) penetrates the distal stopper member (1836). Minimizing the bending of the fluid transfer proximal member (1850) when penetrating the distal stopper member (1836) facilitates the proper functioning of the pre-filled needleless dual-chamber continuous injection system (1800) during continuous injection.

[0204] Figures 113 to 121C show a pre-filled needleless dual-chamber continuous injection system (2700) and a fluid transfer assembly (2776) for use with it, according to several embodiments. The pre-filled needleless dual-chamber continuous injection system (2700) and fluid transfer assembly (2776) are similar to the pre-filled needleless dual-chamber continuous injection system (1800) and fluid transfer assembly (1876) shown in Figures 104 to 112C. The difference between these two systems (2700, 1800) and assemblies (2776, 1876) is that the fluid transfer assembly (2776) shown in Figures 113 to 121C is molded or formed as a single piece (e.g., from a polymer or metal sheet or wire). The fluid transfer assembly (2776) still includes a fluid transfer proximal portion (2750) and a fluid transfer joint portion (2783). By molding or forming the fluid transfer assembly (2776) as a single piece, the manufacturing and assembly of the system are simplified. By forming the fluid transfer assembly (2776), including the fluid transfer joint (2783), from metal, system failure due to stress-induced cracking of the fluid transfer distal anchor portion (2791) of the fluid transfer joint (2783), which may occur in structures formed from polymers, is minimized.

[0205] Figures 113 to 115 are longitudinal cross-sectional views and two progressively detailed longitudinal cross-sectional views showing a pre-filled needleless dual-chamber continuous injection system (2700) according to several embodiments. The pre-filled needleless dual-chamber continuous safety injection system (2700) is similar to the pre-filled dual-chamber continuous injection system (100) shown in Figures 92 to 94. The pre-filled needleless dual-chamber continuous injection system (2700) includes a conventional readily available pre-filled syringe body (2734) in which conventional readily available proximal and distal stopper members (2732, 1836) are disposed inside. The proximal and distal stopper members (2732, 1836), together with the syringe body (2734), define the proximal and distal chambers (2740, 1842). The first and second liquids (2752, 1854) are housed in the distal and proximal chambers (2742, 1840), respectively. The proximal and distal stopper members (2732, 1836) close the proximal and distal ends of the proximal chamber (2740). The distal stopper member (2736) closes the proximal end of the distal chamber (2742). In some embodiments, the distal surface of the proximal stopper member (2732) and the proximal surface of the distal stopper member (2736) are each coated with a lubricating polymer coating (e.g., PTFE or ETFE), and the first and second polymer coatings of the proximal and distal stopper members (2732, 1836), together with the syringe body (2734), define the proximal chamber (2740). The lubricating polymer coating also serves to isolate the rubber of the proximal and distal stopper members (2732, 1836) from the second liquid (2754). The proximal and distal stopper members (2732, 1836) may be oriented as shown in Figures 104 to 106, or the distal stopper (2736) may be inverted so that the lubricating coating faces the distal chamber (2742) so that the first liquid (2752) in the distal chamber (2742) comes into contact with the lubricating coating for storage.

[0206] The dual-chamber continuous injection system (2700) shown in Figures 113 to 115 does not include a “needle” extending outside the syringe body (2734). Instead, the dual-chamber continuous injection system (2700) includes a fluid transfer assembly (2776) molded or formed as a single piece, as described above. The fluid transfer assembly (2776) of the pre-filled needleless dual-chamber continuous injection system (2700) facilitates the continuous injection of a first fluid (2752) from the distal chamber (2742) and then the injection of a second fluid (2754) from the proximal chamber (2740) when the plunger assembly (2744) is continuously inserted into the syringe body (2734) to varying degrees by the user. The plunger assembly (2744) includes a plunger housing member (2769) coupled to a proximal stopper member (2732) and a plunger operating interface (2728). The first liquid and the second liquid (2752, 1854) located in the distal and proximal chambers (2742, 1840), respectively, may be any liquid or gel, such as an aqueous or oily drug solution.

[0207] The fluid transfer assembly (2776) of the pre-filled needleless dual-chamber continuous injection system (2700) is configured for use with a connector (e.g., a Luer lock or Luer slip interface coupled to a needle or fluid transfer tube (not shown) having a sharpened end).

[0208] The fluid transfer assembly (2776) includes a fluid transfer proximal portion (2750, see Figures 114 and 115) and a fluid transfer coupling member (2783, see Figures 114 and 115). The fluid transfer proximal portion (2750) has a proximal channel (2785) molded or formed inside. The fluid transfer coupling portion (2783) is configured to secure the fluid transfer assembly (2776) within the distal opening of the syringe body (2734). The fluid transfer coupling portion (2783) includes a fluid transfer distal anchor (2791), which includes a cylindrical open core (2792) to provide a fit for the fluid transfer distal anchor (2791). The fluid transfer joint (2783) can secure the fluid transfer assembly (2776) to the syringe body (2734) by an interference fit between the fluid transfer distal anchor (2791) and the distal end of the syringe body (2734). The fluid transfer joint (2783) can define one or more channels internally to provide an intermediate opening (2780) between the inside and outside of the syringe body (2734) / distal chamber (2742). The intermediate opening (2780) is located adjacent to the distal end of the syringe body (2734). The proximal longitudinal channel (2785) is defined by the proximal fluid transfer portion (2750).

[0209] Figures 113 to 118 illustrate safe continuous injection methods using the pre-filled needleless dual-chamber continuous injection system (2700) described herein, according to several embodiments.

[0210] Figures 113–115 show a pre-filled needleless dual-chamber continuous injection system (2700) in the first / ready-to-use configuration. The only difference between the first / ready-to-use configuration and the factory-shipped configuration (not shown) is that the syringe body cap (not shown), which is present in the factory-shipped configuration, is removed in the first / ready-to-use configuration.

[0211] In the first / ready-to-use configuration, the proximal longitudinal channel (2785) is located within the distal chamber (2742) together with the intermediate opening (2780). Therefore, there is no flow path between the proximal chamber (2740) and the distal opening (2782). Consequently, any distal force applied to the plunger operating interface (2728) is transferred through the plunger member (2744), the proximal stopper member (2732), and the incompressible second fluid (2754) in the proximal chamber (2740) to move the distal stopper member (2736) distal to the syringe body (2734). As the distal stopper member (2736) moves distally relative to the syringe body (2734), the pressure in the distal chamber (2742) increases, thereby driving the first liquid (2752) out of the distal chamber (2742) through an intermediate opening (2780) formed between the tubular fluid transfer joint (2783) and the distal end of the syringe body (2734) to exit the distal end of the syringe body (2734) (for example, to a Luer connector).

[0212] Figures 116 and 117 show the filled needleless dual-chamber continuous injection system (2700) after the distal stopper member (2736) has been moved distally relative to the syringe body (2734) until the distal stopper member (2736) is almost in contact with the distal end of the syringe body (2736). The distal chamber (2742, see Figure 114) is almost completely crushed / almost completely ejected, and most of the first fluid (2752, see Figure 114) has been discharged from the filled needleless dual-chamber continuous injection system (2700) through the distal end of the syringe body (2736). By moving the distal stopper member (2736) distally relative to the syringe body (2734), the proximal fluid transfer portion (2750) of the fluid transfer assembly (2776) also penetrates the distal stopper member (2736). As the fluid transfer proximal portion (2750) of the fluid transfer assembly (2776) penetrates, the proximal longitudinal channel (2785) is positioned within the proximal chamber (2740) at this point. Therefore, at this point, a flow path exists between the proximal chamber (2740) and the intermediate opening (2780), and the distal force applied to the plunger operating interface (2728) moves the proximal stopper member (2732) distally relative to the syringe body (2734) and the distal stopper member (2736), causing the second liquid (2754) to be discharged from the proximal chamber (2740). Opening the flow path between the proximal chamber (2740) and the distal opening (2782) results in a second configuration of the filled needleless dual-chamber continuous injection system (2700) that allows the second fluid (2754) to be discharged from the proximal chamber (2740) after the first fluid (2752) has been almost completely discharged from the distal chamber (2742).

[0213] Figure 118 shows a pre-filled needleless dual-chamber continuous injection system (2700) after the second fluid (2754, see Figure 107) has been substantially discharged from the proximal chamber (2740, see Figure 96) by the distal movement of the proximal stopper member (2732), and the pre-filled needleless dual-chamber continuous injection system (2700) is in a second configuration.

[0214] Figures 119 to 121C show a fluid transfer assembly (2776) for use with a filled needleless dual chamber continuous injection system (2700) according to some embodiments.

[0215] Figures 119 and 120 are perspective views of a fluid transfer assembly (2776) according to some embodiments. The fluid transfer assembly (2776) includes a fluid transfer proximal portion (2750) and a fluid transfer joint portion (2783). The fluid transfer proximal portion (2750) includes a proximal piercing tip (2784) at its proximal end configured to pierce a distal stopper member (2736). The fluid transfer joint portion (2783) includes a fluid transfer distal anchor (2791) configured to fix the fluid transfer assembly (2776) to the distal opening of the syringe body (2734) by interference fit.

[0216] Figures 121A to 121C are perspective views and axial cross-sectional views of a fluid transfer assembly (2776) according to some embodiments. The fluid transfer proximal portion (2750) includes a proximal piercing tip (2784) at its proximal end and a proximal longitudinal channel (2785) between its proximal end and distal end. The fluid transfer distal anchor (2791) has a triangular cross-sectional shape for providing a flow path leading from an intermediate opening (2780) to the outside of the syringe body (2734). The fluid transfer distal anchor (2791) also defines a cylindrical open core (2792) for providing conformity to the fluid transfer distal anchor (2791), and the cylindrical open core (2792) enables the fluid transfer distal anchor (2791) to be slightly deformed to create an interference fit with the distal opening of the syringe body (2734).

[0217] The diameter of the fluid transfer proximal portion (2750) is also relatively large (for example, about 0.026 inches to about 0.040 inches compared to a cold-formed proximal portion having a diameter of about 0.020 inches). As a result of the larger diameter of the fluid transfer proximal portion (2750), the overall bending moment of inertia is higher, and the resistance to bending is greater, which also improves the probability of capture. Due to its relatively large diameter and solid structure, the fluid transfer proximal portion (2750) has a bending moment of inertia sufficient to improve rigidity and resistance. Resistance to bending is particularly important when the fluid transfer proximal portion (2750) penetrates the distal stopper member (2736). Minimizing the bending of the fluid transfer proximal portion (2750) when penetrating the distal stopper member (2736) facilitates the proper functioning of the pre-filled needleless dual-chamber continuous injection system (2700) during continuous injection.

[0218] Figures 122–123 show perspective views of a fluid transfer assembly (2776') for use with a pre-filled needleless dual-chamber continuous injection system (2700) according to several embodiments. The fluid transfer assembly (2776') is similar to the fluid transfer assembly (2776) shown in Figures 119–121C. The difference between the two fluid transfer assemblies (2776', 2776) is that a rib and draft (2792') are added to the distal end of the proximal fluid transfer portion (2750') to facilitate the penetration of the distal stopper member (2736). Another difference is that the proximal puncture tip (2784') is chamfered to facilitate the penetration of the distal stopper member (2736).

[0219] Exemplary fluid transfer distal anchor Fluid transfer assemblies (1876, 2776, 2776') are described herein in conjunction with fluid transfer distal anchors (1891, 2791, 2791') having a simple triangular cross-section; however, fluid transfer assemblies according to some embodiments may be used with other fluid transfer distal anchors configured to secure the fluid transfer assembly to the distal opening of the syringe body. The fluid transfer distal anchors described herein may be used with any fluid transfer assembly, including the fluid transfer assemblies (1876, 2776, 2776') described herein.

[0220] Figures 124–127B show injection systems (3900) including fluid transfer joint members / parts (3983) according to several embodiments. The rest of the fluid transfer assembly is omitted for clarity. The fluid transfer joint member / part (3983) includes a fluid transfer distal anchor (3991) at its distal end.

[0221] The fluid transfer distal anchor (3991) defines a slot (3993) and includes a biasing member (3994) positioned within the slot (3993). The fluid transfer distal anchor (3991) also defines two pegs (3995) (see Figures 124, 126A, and 126B) configured to hold the biasing member (3994) within the slot (3993). The biasing member (3994) (see Figures 127A and 127B) is a spring-shaped metal loop configured to interfere with the inner diameter of the distal end (3995) of the syringe body (3934) (see Figure 124), creating an interference fit that holds the fluid transfer distal anchor (3991) within the distal end (3995) of the syringe body (3934) while minimizing stress on the rest of the fluid transfer distal anchor (3991).

[0222] Figures 128–130 show injection systems (4100) including fluid transfer joint members / parts (4183) according to several embodiments. The rest of the fluid transfer assembly is omitted for clarity. The fluid transfer joint member / part (4183) includes a fluid transfer distal anchor (4191) at its distal end.

[0223] The fluid transfer distal anchor (4191) takes the form of a corrugated wire segment, configured to interfere with the inner diameter of the distal end (4195) of the syringe body (4134) (see Figure 128) to create an interference fit that holds the fluid transfer distal anchor (4191) within the distal end (4195) of the syringe body (4134). The corrugated wire fluid transfer distal anchor (4191) can be press-fitted into the rest of the fluid transfer joint member / part (4183).

[0224] Figures 131–132B show injection systems (4600) including fluid transfer joint members / parts (4683) according to several embodiments. The rest of the fluid transfer assembly is omitted for clarity. The fluid transfer joint member / part (4683) includes a fluid transfer distal anchor (4691) at its distal end.

[0225] The fluid transfer distal anchor (4691) takes the form of a pair of long, flexible plastic arms configured to interfere with the inner diameter of the distal end (4695) of the syringe body (4634) (see Figure 131), creating an interference fit that holds the fluid transfer distal anchor (4691) within the distal end (4695) of the syringe body (4634) with very low static stress. The length of the flexible plastic arms (4691) and the relatively small interference with the inner diameter of the distal end (4695) of the syringe body (4634) allow the flexible plastic arms (4691) to operate within the elastic range, thereby ensuring that a radial spring force is applied while minimizing static stress and the risk of stress cracking in the glass distal end (4695) of the syringe body (4634) and within the body of the fluid transfer distal anchor (4691).

[0226] Figures 133–135 show injection systems (4700) including fluid transfer joint members / parts (4783) according to several embodiments. The rest of the fluid transfer assembly is omitted for clarity. The fluid transfer joint member / part (4783) includes a fluid transfer distal anchor (4791) at its distal end.

[0227] The fluid transfer distal anchor (4791) includes a recessed portion (4793) and a rubber sleeve (4794) positioned within the recessed portion (4793) and configured to interfere with the inner diameter of the distal end (4795) of the syringe body (4734) (see Figure 133) to create an interference fit that holds the fluid transfer distal anchor (4791) within the distal end (4795) of the syringe body (4734). The fluid transfer distal anchor (4791) also includes proximal and distal openings (4796, 4797) to bypass the seal created by the rubber sleeve (4794) and the distal end (4795) of the syringe body (4734) (see Figure 145).

[0228] Exemplary fluid transfer assembly Figures 136 to 140 show the fluid transfer assembly 5076 in several embodiments. Figure 136 is a longitudinal cross-sectional view showing the fluid transfer assembly 5076 installed within the syringe body 5034 in several embodiments. The fluid transfer assembly 5076 can be used in several embodiments of pre-filled needleless dual-chamber continuous injection systems, such as the pre-filled needleless dual-chamber continuous injection systems 1800 and 2700 shown in Figures 104 to 109 and 113 to 118, respectively. Similar to the fluid transfer assemblies 1876 and 2776, the fluid transfer assembly 5076 is configured for use with dual-chamber continuous injection systems that do not include a “needle” extending outside the syringe body 5034. Furthermore, the fluid transfer assembly 5076 is not configured for use with a needle retraction system, such as that found in the dual-chamber continuous injection system 100 shown in Figures 92 to 94.

[0229] The fluid transfer assembly 5076 is configured to be used with a conventional readily available pre-filled syringe body 5034, and conventional readily available proximal and distal stopper members (not shown) located therein.

[0230] The fluid transfer assembly 5076 facilitates the continuous injection of a first fluid from the distal chamber in the pre-filled needleless dual-chamber continuous injection system, followed by the injection of a second fluid from the proximal chamber, when the plunger assembly is continuously inserted into the syringe body 5034 to varying degrees by the user. The continuous injection system and various system components are similar to those in the pre-filled needleless dual-chamber continuous injection systems 1800 and 2700 shown in Figures 104-109 and 113-118, respectively.

[0231] The fluid transfer assembly 5076 is configured to be used with a connector (for example, a Luer lock or Luer slip interface coupled to a needle or fluid transfer tube (not shown) having a sharpened end). The fluid transfer assembly 5076 includes a fluid transfer proximal member 5050 coupled to the proximal end of the distal fluid transfer distal anchor 5091.

[0232] Figures 137 and 138 show a fluid transfer assembly 5076 according to several embodiments. The fluid transfer assembly 5076 includes a fluid transfer proximal member 5050 partially located within the proximal end of a fluid transfer joint member 5083, the fluid transfer joint member 5083 similarly partially located within the proximal end of a fluid transfer distal anchor 5091. The fluid transfer proximal member 5050 includes a proximal tip 5084 at its proximal end, which is configured to penetrate a distal stopper member during continuous injection. The fluid transfer proximal member 5050 may be a solid metal body, and the fluid transfer joint member 5083 may be a metal tube. The fluid transfer proximal member 5050 may be joined to the fluid transfer joint member 5083 by welding.

[0233] The proximal end of the fluid transfer coupling member 5083 is a split tube, which defines two arms 5082, both of which connect the fluid transfer coupling member 5083 to the fluid transfer distal anchor 5091 and to the fluid transfer assembly 5076 to the syringe body 5034.

[0234] As shown in Figures 139A to 139C, the fluid transfer proximal member 5050 includes a longitudinal opening 5052 and a crossbeam 5054 partially defined therein. The longitudinal opening 5052 is configured to receive two arms 5082 on either side of the crossbeam 5054 during assembly, as shown in Figure 140. After the arms 5082 are inserted past the crossbeam 5054, they plastically deform outward to connect the fluid transfer coupling member 5083 to the fluid transfer distal anchor 5091, preventing the two components from separating without introducing static stress into the fluid transfer distal anchor 5091. The outward plastic deformation of the two arms 5082 mechanically prevents the fluid transfer coupling member 5083 and the fluid transfer distal anchor 5091 from separating without introducing static stress into the fluid transfer distal anchor 5091. The outwardly deformed arm 5082 interferes with the inner diameter of the distal end 5096 of the syringe body 5034 (see Figure 136), creating an interference fit that connects the fluid transfer assembly 5076 to the distal end 5096 of the syringe body 5034, while minimizing stress on the rest of the fluid transfer distal anchor 5091, which may be formed from polymer.

[0235] Figures 141 and 142 show the fluid transfer assembly 5176 in several embodiments. Figure 141 is a longitudinal cross-sectional view showing the fluid transfer assembly 5176 installed within a syringe body 5134 in several embodiments. The fluid transfer assembly 5176 is similar to the fluid transfer assembly 5076 shown in Figures 136-140 in that it does not include a “needle” extending outside the syringe body 5134 and is configured for use with a dual-chamber continuous injection system configured for use with a non-retractable system. The fluid transfer assembly 5176 also includes a fluid transfer proximal member 5150 coupled to the proximal end of the fluid transfer distal anchor distal 5191. The difference between the fluid transfer assemblies 5076 and 5176 shown in Figures 136 and 141 is that the fluid transfer proximal member 5150 extends distally and defines a pair of arms 5182 instead of connecting to a tubular member that divides distally.

[0236] The fluid transfer distal anchor 5191 shown in Figure 141 is identical to the fluid transfer distal anchor 5091 shown in Figure 136. During assembly, the arm 5182 is inserted past the crossbeam 5154, and the arm 5182 is plastically deformed outward to connect the fluid transfer proximal member 5150 to the fluid transfer distal anchor 5191, preventing the two components from separating without introducing static stress to the fluid transfer distal anchor 5191. The outwardly deformed arm 5182 also interferes with the inner diameter of the distal end 5196 of the syringe body 5134 (see Figure 141), creating an interference fit that connects the fluid transfer assembly 5176 to the distal end 5196 of the syringe body 5134, while minimizing stress on the rest of the fluid transfer distal anchor 5191, which may be formed from plastic and polymer.

[0237] Exemplary fluid transfer distal anchor Figures 143–145C show an injection system 5200 including a fluid transfer joint member / part 5283 according to several embodiments. The rest of the fluid transfer assembly is omitted for clarity. As shown in Figures 143 and 144A, the fluid transfer joint member / part 5283 includes a fluid transfer distal anchor 5291 at its distal end.

[0238] The fluid transfer distal anchor 5291 defines a slot 5293, and the fluid transfer joint member / part 5283 includes a rhombic biasing member 5294 positioned within the slot 5293. The fluid transfer distal anchor 5291 also defines two bumps 5295 (see Figures 143 and 145A-145C), and the biasing member 5294 defines two notches 5297 configured to receive the two bumps 5295 and maintain the biasing member 5294 within the slot 5293 (see Figures 143 and 145B-145C). The biasing member 5294 (see Figures 144B and 145A) is a spring-shaped rhomboid metal loop configured to interfere with the inner diameter of the distal end 5296 of the syringe body 5234 (see Figure 143) to create an interference fit that holds the fluid transfer distal anchor 5291 within the distal end 5296 of the syringe body 5234 while minimizing stress on the rest of the fluid transfer distal anchor 5291.

[0239] Figures 144B and 145A show the rhombic biasing member 5294 before insertion into the slot 5293 defined by the fluid transfer distal anchor 5291. Figure 145B shows the insertion of the rhombic biasing member 5294 into the slot 5293 defined by the fluid transfer distal anchor 5291. In Figure 145B, the rhombic biasing member 5294 is in a "free" state, able to pass between the two bumps 5295 defined by the fluid transfer distal anchor 5291.

[0240] In Figure 145C, after the rhombic biasing member 5294 is inserted into the slot 5293 defined by the fluid transfer distal anchor 5291, the rhombic biasing member 5294 is compressed and plastically deformed so that a pair of notches 5297 engage with a pair of bumps 5295. The engagement of the notches 5297 with the pair of bumps 5295 mechanically couples the rhombic biasing member 5294 to the fluid transfer distal anchor 5291 without introducing any static stress to the fluid transfer distal anchor 5291. Figure 145C shows the fluid transfer joint member / part 5283 after assembly, as shown in Figure 144A.

[0241] When the fluid transfer joint member / part 5283 is inserted into the distal end 5296 of the syringe body 5234 (see Figure 143), the rhombic biasing member 5294 interferes with the inner diameter of the distal end 5296 of the syringe body 5234, creating an interference fit that holds the fluid transfer distal anchor 5291 within the distal end 5296 of the syringe body 5234.

[0242] X. Exemplary dual-chamber injection system Figures 146–148C show a dual-chamber safety injection system 5300 having a syringe body 5320 in which a one-way valve 5400 is located at its distal end, according to several embodiments. The dual-chamber safety injection system 5300 also includes a needle assembly 5350 extending through the one-way valve 5400, as well as proximal and distal stopper members 5340, 5390 located inside the syringe body 5320. The proximal and distal stopper members 5340, 5390 define the proximal and distal chambers 5360, 5370 inside the syringe body 5320. The dual-chamber safety injection system 5300 also includes a plunger member 5330 which includes a needle retraction system. The needle retraction system is located substantially inside the plunger member 5330.

[0243] In some embodiments, a liquid drug component is placed in the proximal chamber 5360, and a powder (e.g., lyophilized) drug component is placed in the distal chamber 5370. The dual-chamber safety injection system 5300 is configured such that by applying a distal force to the plunger member 5330, the proximal stopper member 5340 moves distally, transferring the liquid drug component from the proximal chamber 5360 to the distal chamber 5370. The dual-chamber safety injection system 5300 is then agitated (e.g., inverted) to mix the liquid and powder drug components, forming a mixed liquid drug. Subsequently, by continuing to apply a distal force to the plunger member 5330, the proximal stopper member and the distal stopper members 5340, 5390 move distally, and the mixed liquid drug is discharged from the distal chamber 5370 through the needle assembly 5350. After the mixed liquid drug is discharged from the distal chamber 5370, the needle retraction system within the plunger member 5330 retracts the needle assembly 5350 at least partially into the plunger member 5330, positioning the sharp distal end of the needle assembly 5350 inside the syringe body 5320.

[0244] The one-way valve 5400 is shown in detail in Figures 148A to 148C. As shown in Figure 148C, the one-way valve 5400 includes a rigid (e.g., plastic) proximal portion 5410 having a circular base 5412 that defines a pair of lateral openings 5414 and a sleeve 5416 that extends distally from its center. The sleeve 5416 defines a plurality of longitudinal channels 5418 on its outer surface.

[0245] The one-way valve 5400 also includes a flexible / bendable (e.g., rubber) distal portion 5420 having a central opening 5422 configured to receive a sleeve 5416. As shown in Figure 147, the sleeve 5416 has an inner diameter only slightly larger than the outer diameter of the portion of the needle assembly 5350 through which it passes. This strict tolerance prevents powdered drug components from inadvertently passing through the one-way valve 5400 and entering and clogging the needle assembly 5350. The tolerances between the lateral openings 5414 of the one-way valve 5400 and the proximal and distal portions 5410, 5420 are also strict enough to prevent powdered drug components from passing through. The flexible distal portion 5420 stretches around the circular base 5412 of the rigid proximal portion 5410 to tightly fit and close the two lateral openings 5414, preventing any powdered drug components from passing through. On the other hand, the one-way valve 5400 allows the mixed liquid drug to enter the needle assembly 5350 through the intermediate opening 5352 (see Figure 147) between the proximal and distal portions 5410, 5420 of the one-way valve 5400, along multiple longitudinal channels 5418 on the sleeve 5416, under pressure (described later), and exit the dual-chamber safety injection system 5300. Thus, the one-way valve 5400 prevents powder drug components from passing through it and clogging the needle assembly 5350, while allowing liquids (e.g., mixed liquid drug) to pass through (e.g., under pressure exerted by the plunger member) and exit the dual-chamber safety injection system 5300 through the needle assembly 5350.

[0246] In its default assembled state, the proximal and distal portions 5410 and 5420 of the one-way valve 5400 contact each other on the distal surface of the circular base 5412, closing the two lateral openings 5414 and preventing the powdered drug components from leaving the distal chamber 5370. However, after the liquid drug has been mixed and is ready for injection, a distal force applied to the plunger member 5330 generates pressure within the distal chamber 5370, thereby discharging the mixed liquid drug under pressure. The pressure in the distal chamber causes the flexible distal portion 5420 of the one-way valve 5400 to separate from the rigid proximal portion 5410 of the one-way valve 5400, thereby removing the blockage of the two lateral openings 5414, allowing the mixed liquid drug to enter the needle assembly 5350 through the intermediate opening 5352, along the multiple longitudinal channels 5418 on the sleeve 5416, under pressure, and be transported out of the dual-chamber safety injection system 5300 (see Figure 147).

[0247] The pre-filled dual-chamber safety injection systems shown and described herein include syringes with crimped needles, but various configurations / embodiments described herein (e.g., continuous injection, detent dual chambers, screw-type plunger members, and shielded ventilated needle covers) can be used with needleless injection systems having cartridges, auto-injectors, and Luer connectors and transfer pipes.

[0248] Various exemplary embodiments of the present invention are described herein. These examples are used in a non-limiting sense. These examples are given to illustrate broader applicable aspects of the present invention. Various modifications can be made to the described invention and replaced with equivalents without departing from the true spirit and scope of the invention. In addition, many modifications can be made to adapt specific situations, materials, material compositions, processes, process operations, or steps to the object, spirit, or scope of the present invention. Furthermore, as will be understood by those skilled in the art, each of the individual modifications described and illustrated herein has distinct components and features that can be readily separated or combined with features of any of several other embodiments without departing from the scope or spirit of the present invention. All such modifications are intended to be within the scope of the claims associated with this disclosure.

[0249] Any of the devices described for performing the diagnostic or interventional procedures of this subject may be provided in a packaged combination for use in carrying out such interventions. These supplies “kits” may further include instructions for use and packaging in disinfection trays or containers as commonly used for such purposes.

[0250] The present invention includes methods that can be carried out using the device of the subject matter. The methods may include operations to provide such a suitable device. Such provision may be carried out by an end user. In other words, the “providing” operation requires only that the end user perform acquisition, access, approach, positioning, setup, startup, power-on, or other operations to provide the device required in the method of the subject matter. The methods described herein may perform the described events in any logically possible order, as well as in the order described.

[0251] Exemplary embodiments of the present invention, along with details relating to material selection and manufacturing, are described above. As with other details of the present invention, these may be understood in relation to the patents and publications referenced above and those generally known or understood by those skilled in the art. For example, it will be understood by those skilled in the art that one or more lubricating coatings (e.g., hydrophilic polymers such as polyvinylpyrrolidone compositions, fluoropolymers such as tetrafluoroethylene, PTFE, ETFE, hydrophilic gels, or silicones) may be used, if desired, in relation to various parts of a device, such as relatively large interfaces of movable joints, for example, to facilitate low-friction operation or advancement of such objects against other parts of the instrument or nearby structural elements. The same may apply in relation to method-based embodiments of the present invention with respect to additional operations that are commonly or logically utilized.

[0252] In addition, although the present invention has been described with reference to several examples that optionally incorporate various features, the present invention is not limited to those described or shown as intended in relation to each variation of the present invention. Various modifications can be made to the described invention without departing from the true spirit and scope of the invention, and equivalents (whether described or not included herein for a certain degree of brevity) can be substituted. In addition, if a range of values ​​is given, it is understood that all intervening values ​​between the upper and lower limits of that range, and any other described or intervening values ​​within that described range, are encompassed within the present invention.

[0253] Furthermore, it is intended that any optional feature of the variants of the invention described herein may be described independently or in combination with any one or more of the features described herein and may be claimed. References to singular items include the possibility that there may be multiple instances of the same item. More specifically, as used herein and in the appended claims, the singular forms “a,” “an,” “said,” and “the” include multiple references unless specifically otherwise specified. In other words, the use of articles allows for “at least one” of the subject matter in the claims associated with the above description and this disclosure. It should be further noted that such claims may be written to exclude any optional element. Thus, this statement is intended to serve as an antecedent to the use of exclusive terms such as “solely,” “only,” or “negative” limitation relating to the description of claim elements.

[0254] Unless such exclusive terminology is used, the term “comprising” in any claim associated with this disclosure shall allow for the inclusion of any additional elements, regardless of whether a given number of elements are enumerated in such claim, or whether the addition of an element could be considered to alter the nature of the elements described in such claim. Unless specifically defined herein, all technical and chemical terms used herein shall be given meanings that are as broadly and generally understood as possible while maintaining the validity of the claims.

[0255] The scope of the present invention is not limited to the examples and / or details of the subject matter provided, but rather is limited only by the language of the claims associated with this disclosure.

Claims

1. A system for continuously injecting liquids, A syringe body that defines the proximal opening of the syringe and the distal needle interface at its distal end, A proximal stopper member and a distal stopper member disposed within the syringe body, wherein a proximal chamber is formed between the proximal stopper member and the distal stopper member, and a distal chamber is formed between the distal stopper member and the distal end of the syringe body, The first liquid in the distal chamber, The second liquid in the proximal chamber, A plunger is configured to be manually operated to insert the proximal stopper member distally to the syringe body, The syringe body comprises a needle hub assembly coupled to the distal needle interface, the needle assembly including a needle, The needle defines the inside of the needle, the distal end opening, the intermediate opening, and the proximal opening. The distal end opening, the intermediate opening, and the proximal opening are fluidly coupled through the inside of the needle. A system in which, by operating the plunger member to insert the proximal stopper member distally to the syringe body, the first liquid is first discharged from the distal chamber through the needle, and then, continuously, the second liquid is discharged from the proximal chamber through the needle.

2. The needle comprises a tubular member and a solid proximal end feature portion connected thereto. The system according to claim 1, wherein the inside of the needle, the distal end opening, the intermediate opening, and the proximal opening are formed within the tubular member.

3. The system according to claim 2, wherein the solid proximal end feature portion is joined to the tubular member by welding.

4. The system according to claim 3, wherein the welding is a fillet weld configured to reduce the cutting of the proximal stopper member when the needle penetrates the proximal stopper member, compared to a needle that does not use fillet welding.

5. The system according to claim 3, wherein the welded portion is tapered in the proximal direction.

6. The system according to claim 3, wherein the proximal opening is adjacent to the welded portion.

7. The system according to claim 2, wherein the solid proximal end feature portion is cold-formed.

8. The system according to claim 2, wherein the distal end of the solid proximal end feature portion is located within the proximal end of the tubular member.

9. The system according to claim 8, wherein the distal end of the solid proximal end feature portion and the proximal end of the tubular member define an annular lumen that fluidly connects the proximal opening to the inside of the needle, the intermediate opening, and the distal end opening.

10. The system according to claim 1, wherein the proximal opening has a rounded edge configured to reduce the cutting of the proximal stopper member when the needle penetrates the proximal stopper member, compared to a needle without a rounded edge.

11. The system according to claim 1, wherein the proximal opening is an elongated slot.

12. The system according to claim 11, wherein the length of the elongated slot provides an allowable range for variations related to the proximal stopper member and / or the distal stopper member.

13. The system according to claim 12, wherein the variation relating to the proximal stopper member and / or the distal stopper member is selected from the group consisting of the distortion of the proximal surface of the distal stopper member, the position of the proximal stopper member with respect to the elongated slot, and the position of the distal stopper member with respect to the elongated slot.

14. The system according to claim 12, wherein the length of the elongated slot is approximately 1 / 32 inch to approximately 1 / 16 inch.

15. The system according to claim 11, wherein the distance between the elongated slot and the solid proximal end minimizes backflow leakage of the first liquid and the second liquid to the plunger.

16. The system according to claim 11, wherein the elongated slot is formed using a grinding wheel.

17. The system according to claim 1, wherein the first and second sizes of the respective distal chamber and proximal chamber can be changed by moving the proximal stopper member and the distal stopper member relative to the syringe body.

18. The plunger member is The needle retention feature section located inside the plunger, An energy storage member is disposed inside the plunger, The plunger comprises an energy storage member latch member located inside the plunger, The aforementioned needle hub assembly is Hub and, The system comprises a needle holding member configured to connect the needle to the hub, The system according to claim 1, wherein the needle is at least partially retractable into the plunger when the plunger member is operated relative to the syringe body to convert the energy storage member latch member from a latched state to an unlatched state.

19. The system according to claim 18, wherein the needle is configured to completely puncture at least the distal stopper member so that it is at least partially drawn into the plunger.

20. The system according to claim 18, wherein the energy storage member latch member is configured to convert from the latched state to the non-latched state, which at least partially pulls the needle into the plunger after the second liquid has been discharged from the proximal chamber through the needle.

21. The system according to claim 18, wherein the needle retention feature is configured to activate the conversion of the energy storage member latch member from the latched state to the unlatched state when the plunger member is operated to insert the proximal stopper member into the distal end of the syringe body.

22. The system according to claim 1, wherein the distance between the proximal opening and the distal end of the syringe body is substantially equal to the length of the distal stopper member, and as a result, when the distal stopper member is inserted into the distal end of the syringe body, the proximal stopper member is inserted distally to the needle, and the proximal opening is positioned within the proximal chamber.

23. The system according to claim 1, wherein the proximal stopper member, the distal stopper member, and the syringe body are configured such that a distal force applied to the proximal stopper member is transmitted to the distal stopper member through the second liquid until the proximal stopper member is inserted distally to the needle and the proximal opening is positioned within the proximal chamber.

24. The aforementioned system, A first injection configuration in which the proximal opening is located within the distal chamber or the distal stopper member, The system according to claim 1, further comprising a second injection configuration in which the proximal opening is located within the proximal chamber, thereby enabling the second liquid to be transferred from the proximal chamber through the proximal opening and the inside of the needle and out through the distal end opening.

25. The system according to claim 1, wherein the proximal stopper member and the distal stopper member each include a first polymer coating and a second polymer coating on their respective distal and proximal surfaces, respectively, and as a result the proximal chamber is defined by the syringe body and the first polymer coating and the second polymer coating.

26. The distal stopper member is, A funnel that tapers proximally, The system according to claim 1, further comprising a space located at the tapered proximal end of the funnel.

27. The system according to claim 1, wherein the intermediate opening is adjacent to the distal end of the syringe body.

28. A method for sequentially injecting a first liquid and a second liquid into a patient, The objective is to provide a system, wherein the system is A syringe body that defines the proximal opening of the syringe and the distal needle interface at its distal end, A proximal stopper member and a distal stopper member disposed within the syringe body, wherein a proximal chamber is formed between the proximal stopper member and the distal stopper member, and a distal chamber is formed between the distal stopper member and the distal end of the syringe body, The first liquid in the distal chamber, The second liquid in the proximal chamber, A plunger is configured to be manually operated to insert the proximal stopper member distally to the syringe body, To provide a system comprising a needle having an internal core, a distal end opening, an intermediate opening, and a proximal opening, wherein the distal end opening, the intermediate opening, and the proximal opening are fluidly coupled through the internal core of the needle, The plunger member is advanced to discharge a first portion of the first liquid from the distal chamber through the inside of the needle and the distal end opening, Further advancing the plunger member to discharge the second liquid from the proximal chamber through the proximal opening, the inside of the needle, and the distal end opening, A method comprising further advancing the plunger member to discharge a second portion of the first liquid from the proximal chamber through the inside of the needle and the distal end opening.

29. The method according to claim 28, further comprising automatically retracting the distal needle tip into the needle hub or the syringe body when the second portion of the first liquid is discharged through the distal end opening.

30. The needle shall completely puncture at least the distal stopper member, The method according to claim 29, further comprising drawing the needle at least partially into the plunger.

31. The method according to claim 28, further comprising inserting the distal end of the needle into the patient before advancing the plunger member to discharge the first portion of the first liquid from the distal chamber, thereby positioning the distal end opening of the needle into the patient before the first portion of the first liquid is discharged.

32. The method according to claim 31, further comprising removing air from the distal chamber before inserting the distal end of the needle into the patient.

33. Removing air from the distal chamber is The syringe body is held in a substantially vertical position, The method according to claim 32, further comprising operating the plunger member to insert the proximal stopper member distally to the syringe body.

34. The method according to claim 28, wherein by advancing the plunger member, the proximal stopper member is inserted distally to the syringe body, thereby applying a distal force through the second liquid, the distal stopper member is inserted distally to the syringe body, and the first portion of the first liquid is discharged from the distal chamber through the inside of the needle and the distal end opening.

35. The aforementioned system, A first injection configuration in which the proximal opening is located within the distal chamber or the distal stopper member, A second injection configuration in which the proximal opening is positioned within the proximal chamber, thereby enabling the second liquid to be transferred from the proximal chamber through the proximal opening and the inside of the needle and exit through the distal end opening, The injection configuration includes a third injection configuration in which the proximal stopper member and the distal stopper member are in contact with each other, and the proximal opening is closed by the proximal stopper member and / or the distal stopper member, The system is in the first injection configuration when the plunger member is advanced and the first portion of the first liquid is discharged from the distal chamber through the inside of the needle and the distal end opening. The system is in the second injection configuration when the plunger member is further advanced and the second liquid is discharged from the proximal chamber through the proximal opening, the inside of the needle and the distal end opening. The method according to claim 28, wherein the system is in the third injection configuration when the plunger member is advanced and the second portion of the first liquid is discharged from the distal chamber through the inside of the needle and the distal end opening.

36. The needle comprises a tubular member and a solid proximal end feature portion connected thereto. The method according to claim 28, wherein the inside of the needle, the distal end opening, the intermediate opening, and the proximal opening are formed within the tubular member.

37. The method according to claim 36, wherein the solid proximal end feature portion is joined to the tubular member by welding.

38. The method according to claim 37, wherein the welding is a fillet weld configured to reduce the cutting of the proximal stopper member when the needle penetrates the proximal stopper member, compared to a needle that does not use fillet welding.

39. The method according to claim 36, wherein the distal end of the solid proximal end feature portion is located within the proximal end of the tubular member.

40. The method according to claim 39, wherein the distal end of the solid proximal end feature portion and the proximal end of the tubular member define an annular lumen that fluidly connects the proximal opening to the inside of the needle, the intermediate opening, and the distal end opening.

41. The method according to claim 28, wherein the proximal opening has a rounded edge configured to reduce the cutting of the proximal stopper member when the needle penetrates the proximal stopper member, compared to a needle without a rounded edge.

42. The method according to claim 28, wherein the proximal opening is an elongated slot.

43. The method according to claim 42, wherein the length of the elongated slot provides an allowable range for variations related to the proximal stopper member and / or the distal stopper member.

44. The method according to claim 43, wherein the variation relating to the proximal stopper member and / or the distal stopper member is selected from the group consisting of the distortion of the proximal surface of the distal stopper member, the position of the proximal stopper member with respect to the elongated slot, and the position of the distal stopper member with respect to the elongated slot.

45. The method according to claim 43, wherein the length of the elongated slot is approximately 1 / 32 inch to approximately 1 / 16 inch.

46. The method according to claim 42, wherein the length of the elongated slot minimizes backflow leakage of the first liquid and the second liquid to the plunger.

47. The distal stopper member is, A funnel that tapers proximally, The funnel has a space located at its tapered proximal end, The method according to claim 28, further comprising the funnel guiding the needle into the space at the tapered proximal end of the funnel, thereby aligning the proximal end feature of the needle with the needle retention feature inside the plunger.

48. The method according to claim 28, wherein the intermediate opening is adjacent to the distal end of the syringe body.

49. A system for continuously injecting liquids, A syringe body that defines the proximal opening of the syringe and the distal needle interface at its distal end, The proximal stopper member, intermediate stopper member, and distal stopper member are arranged within the syringe body, The proximal chamber between the proximal stopper member and the intermediate stopper member, The intermediate chamber between the intermediate stopper member and the distal stopper member, and A proximal stopper member, an intermediate stopper member, and a distal stopper member form a distal chamber between the distal stopper member and the distal end of the syringe body. The first liquid in the distal chamber, The second liquid in the intermediate chamber, The third liquid in the proximal chamber, A plunger is configured to be manually operated to insert the proximal stopper member distally to the syringe body, The syringe body comprises a needle hub assembly coupled to the distal needle interface, the needle assembly including a needle, The needle defines the inside of the needle, the distal end opening, the intermediate opening, and the proximal opening. The distal end opening, the intermediate opening, and the proximal opening are fluidly coupled through the inside of the needle. A system in which the first liquid, the second liquid, and the third liquid are continuously dispensed through the needle by operating the plunger member to insert the proximal stopper member distally to the syringe body.

50. By operating the plunger member to insert the proximal stopper member distally to the syringe body, the first liquid, the second liquid, and the third liquid are dispensed through the needle. The first portion of the first liquid from the distal chamber, The second liquid from the intermediate chamber, The second portion of the first liquid from the distal chamber, and The system according to claim 49, wherein the third liquid is continuously discharged from the proximal chamber in that order.

51. By operating the plunger member to insert the proximal stopper member distally to the syringe body, the first liquid, the second liquid, and the third liquid are dispensed through the needle. The first liquid from the distal chamber, The second liquid from the intermediate chamber, and The system according to claim 49, wherein the third liquid is continuously discharged from the proximal chamber in that order.

52. The needle comprises a tubular member and a solid proximal end feature portion connected thereto. The system according to claim 49, wherein the inside of the needle, the distal end opening, the intermediate opening, and the proximal opening are formed within the tubular member.

53. The system according to claim 52, wherein the solid proximal end feature portion is joined to the tubular member by welding.

54. The system according to claim 53, wherein the welding is a fillet weld configured to reduce the cutting of the proximal stopper member and the intermediate stopper member when the needle penetrates the proximal stopper member and the intermediate stopper member, compared to a needle that does not use fillet welding.

55. The system according to claim 53, wherein the welded portion is tapered in the proximal direction.

56. The system according to claim 52, wherein the solid proximal end feature portion is cold-formed.

57. The system according to claim 52, wherein the distal end of the solid proximal end feature portion is located within the proximal end of the tubular member.

58. The system according to claim 57, wherein the distal end of the solid proximal end feature and the proximal end of the tubular member define an annular lumen that fluidly connects the proximal opening to the inside of the needle, the intermediate opening, and the distal end opening.

59. The system according to claim 49, wherein the proximal opening has a rounded edge configured to reduce the cutting of the proximal stopper member and the intermediate stopper member when the needle penetrates the proximal stopper member and the intermediate stopper member, compared to a needle without a rounded edge.

60. The system according to claim 49, wherein the proximal opening is an elongated slot.

61. The system according to claim 60, wherein the length of the elongated slot provides an allowable range for variations relating to the proximal stopper member, the intermediate stopper member, and / or the distal stopper member.

62. The system according to claim 61, wherein the fluctuation relating to the proximal stopper member and / or the distal stopper member is selected from the group consisting of the strain on the proximal surface of the distal stopper member, the strain on the proximal surface of the intermediate stopper member, the position of the proximal stopper member with respect to the elongated slot, the position of the intermediate stopper member with respect to the elongated slot, and the position of the distal stopper member with respect to the elongated slot.

63. The system according to claim 61, wherein the length of the elongated slot is approximately 1 / 16 inch to approximately 1 / 8 inch.

64. The system according to claim 60, wherein the distance between the elongated slot and the solid proximal end minimizes backflow leakage of the first liquid, the second liquid, and the third liquid to the plunger.

65. The system according to claim 60, wherein the elongated slot is formed using a grinding wheel.

66. The system according to claim 49, wherein the first, second, and third sizes of each of the distal chamber, intermediate chamber, and proximal chamber can be changed by moving the proximal stopper member, intermediate stopper member, and distal stopper member relative to the syringe body.

67. The plunger member is The needle retention feature section located inside the plunger, An energy storage member is disposed inside the plunger, The plunger comprises an energy storage member latch member located inside the plunger, The aforementioned needle hub assembly is Hub and, The system comprises a needle holding member configured to connect the needle to the hub, The system according to claim 49, wherein the needle is at least partially retractable into the plunger when the plunger member is operated relative to the syringe body to convert the energy storage member latch member from a latched state to an unlatched state.

68. The system according to claim 67, wherein the needle is configured to completely puncture at least the distal stopper member and the intermediate stopper member so that it is at least partially drawn into the plunger.

69. The system according to claim 67, wherein the energy storage member latch member is configured to convert from the latched state to the non-latched state, which at least partially retracts the needle into the plunger after the third liquid has been discharged from the proximal chamber through the needle.

70. The system according to claim 67, wherein the needle retention feature is configured to activate the conversion of the energy storage member latch member from the latched state to the unlatched state when the plunger member is operated to insert the proximal stopper member into the distal end of the syringe body.

71. The system according to claim 49, wherein the proximal stopper member, the intermediate stopper member, the distal stopper member, and the syringe body are configured such that, until the proximal stopper member is inserted distally to the needle and the proximal opening is positioned within the intermediate chamber, distal forces applied to the proximal stopper member are transmitted to the intermediate stopper member through the third liquid and to the distal stopper member through the second liquid.

72. The aforementioned system, A first injection configuration in which the proximal opening is located within the distal chamber or the distal stopper member, A second injection configuration in which the proximal opening is positioned within the intermediate chamber, thereby enabling the second liquid to be transferred from the intermediate chamber through the proximal opening and the inside of the needle and exit through the distal end opening, The system according to claim 49, further comprising a third injection configuration in which the proximal opening is located within the proximal chamber, thereby enabling the third liquid to be transferred from the proximal chamber through the proximal opening and the inside of the needle and out through the distal end opening.

73. The system according to claim 49, wherein the proximal stopper member and the intermediate stopper member each include a first polymer coating and a second polymer coating on their respective distal and proximal surfaces, and as a result the proximal chamber is defined by the syringe body and the first polymer coating and the second polymer coating.

74. The distal stopper member is, A funnel that tapers proximally, The system according to claim 49, further comprising a space located at the tapered proximal end of the funnel.

75. The system according to claim 49, wherein the intermediate opening is adjacent to the distal end of the syringe body.

76. A method for sequentially injecting a first liquid and a second liquid into a patient, The objective is to provide a system, wherein the system is A syringe body that defines the proximal opening of the syringe and the distal needle interface at its distal end, The proximal stopper member, intermediate stopper member, and distal stopper member are arranged within the syringe body, The proximal chamber between the proximal stopper member and the intermediate stopper member, The intermediate chamber between the intermediate stopper member and the distal stopper member, and A proximal stopper member, an intermediate stopper member, and a distal stopper member form a distal chamber between the distal stopper member and the distal end of the syringe body. The first liquid in the distal chamber, The second liquid in the intermediate chamber, The third liquid in the proximal chamber, A plunger is configured to be manually operated to insert the proximal stopper member distally to the syringe body, To provide a system comprising a needle having an internal core, a distal end opening, an intermediate opening, and a proximal opening, wherein the distal end opening, the intermediate opening, and the proximal opening are fluidly coupled through the internal core of the needle, The plunger member is advanced to discharge a first portion of the first liquid from the distal chamber through the inside of the needle and the distal end opening, Further advancing the plunger member to discharge the second liquid from the intermediate chamber through the proximal opening, the inside of the needle, and the distal end opening, Further advancing the plunger member to discharge the second portion of the first liquid from the proximal chamber through the inside of the needle and the distal end opening, A method comprising further advancing the plunger member to discharge the third liquid from the proximal chamber through the proximal opening, the inside of the needle, and the distal end opening.

77. The method according to claim 76, further comprising automatically retracting the distal needle tip into the needle hub or the syringe body when the second portion of the first liquid is discharged through the distal end opening.

78. A method for sequentially injecting a first liquid and a second liquid into a patient, The objective is to provide a system, wherein the system is A syringe body that defines the proximal opening of the syringe and the distal needle interface at its distal end, The proximal stopper member, intermediate stopper member, and distal stopper member are arranged within the syringe body, The proximal chamber between the proximal stopper member and the intermediate stopper member, The intermediate chamber between the intermediate stopper member and the distal stopper member, and A proximal stopper member, an intermediate stopper member, and a distal stopper member form a distal chamber between the distal stopper member and the distal end of the syringe body. The first liquid in the distal chamber, The second liquid in the intermediate chamber, The third liquid in the proximal chamber, A plunger is configured to be manually operated to insert the proximal stopper member distally to the syringe body, To provide a system comprising a needle having an internal core, a distal end opening, an intermediate opening, and a proximal opening, wherein the distal end opening, the intermediate opening, and the proximal opening are fluidly coupled through the internal core of the needle, The plunger member is advanced to discharge the first liquid from the distal chamber through the inside of the needle and the distal end opening, Further advancing the plunger member to discharge the second liquid from the intermediate chamber through the proximal opening, the inside of the needle, and the distal end opening, A method comprising further advancing the plunger member to discharge the third liquid from the proximal chamber through the proximal opening, the inside of the needle, and the distal end opening.

79. The method according to claim 78, further comprising automatically retracting the distal needle tip into the needle hub or the syringe body when the third liquid is discharged through the distal end opening.

80. Syringe assembly, A syringe body having an internal, proximal and distal end, and a needle attachment interface located at the distal end, Proximal section, Intermediate connector, and A needle assembly having a distal portion, The device comprises a needle latch assembly configured to prevent the needle assembly from moving proximal in a closed state and to release the needle assembly in an open state to allow the needle assembly to move proximal, The aforementioned proximal portion has a crescent or dumbbell-shaped cross-section. A syringe assembly wherein the needle assembly is configured to be retracted into the syringe body after injection using the syringe assembly.

81. The aforementioned proximal portion includes multiple leaf parts, The assembly according to claim 80, wherein two of the plurality of leaf portions form an angle of approximately 90°.

82. The assembly according to claim 80, wherein the proximal portion includes a section having a taper of about 12° to 15°.

83. The aforementioned proximal portion is The reduced diameter section, The assembly according to claim 80, comprising a proximal tip having a distally facing projection to the reduced diameter section of approximately 0.0075 inches.

84. The assembly according to claim 80, wherein the distal portion includes a sharp distal end.

85. The system further comprises a proximal stopper member and a distal stopper member. The proximal stopper member, the distal stopper member, and the syringe body define the proximal chamber. The assembly according to claim 80, wherein the distal stopper member and the syringe body define the distal chamber.

86. The assembly according to claim 85, wherein the needle assembly comprises a radially extending annular flange adjacent to the proximal end of the intermediate connector.

87. The assembly according to claim 85, wherein the distal portion includes a radially enlarged portion that defines a longitudinal tube having a squirrel cross-sectional shape.

88. The assembly according to claim 85, wherein the distal portion includes a radially smaller portion having a rounded triangular cross-sectional shape.

89. The assembly according to claim 85, wherein the distal stopper member includes a stopper insert having a pair of tabs.

90. The syringe assembly according to claim 85, wherein the syringe assembly is configured to transfer a fluid from the proximal chamber to the distal chamber, mix it with components in the distal chamber, and then discharge the mixed fluid and components from the distal chamber.

91. The assembly according to claim 85, wherein the syringe assembly is configured to discharge fluid from the distal chamber and subsequently discharge fluid from the proximal chamber.

92. The assembly according to claim 85, wherein the proximal portion has two separate compartments, each having a crescent or dumbbell-shaped cross-section.

93. Syringe assembly, A syringe body having an internal structure, a proximal end and a distal end, A syringe assembly comprising a needle assembly having a flow regulator positioned adjacent to the distal end of the syringe body.

94. The assembly according to claim 93, wherein the flow regulator comprises a housing, the housing defining a liquid port and a compliant pin.

95. The assembly according to claim 94, wherein the flow regulator comprises an elastic seal configured to form a fluid-tight seal between the housing and the distal end of the syringe body.

96. The assembly according to claim 95, wherein the elastic seal is configured to close the liquid port when low pressure is present in the internal chamber of the syringe body.

97. The assembly according to claim 95, wherein the elastic seal is configured to open the liquid port when high pressure is present in the internal chamber of the syringe body.

98. The assembly according to claim 93, further comprising a stopper member having a stopper insert.

99. The assembly according to claim 98, wherein the stopper insert has an internal shape complementary to the external shape of the flow regulator.

100. A system for continuously injecting liquids, A syringe body that defines the proximal opening of the syringe and the distal needle interface at its distal end, A proximal stopper member and a distal stopper member disposed within the syringe body, wherein a proximal chamber is formed between the proximal stopper member and the distal stopper member, and a distal chamber is formed between the distal stopper member and the distal end of the syringe body, The first liquid in the distal chamber, The second liquid in the proximal chamber, A plunger is configured to be manually operated to insert the proximal stopper member distally to the syringe body, Proximal section, Intermediate connector, and A needle assembly having a distal portion, The aforementioned proximal portion has a crescent or dumbbell-shaped cross-section. A system in which, by operating the plunger member to insert the proximal stopper member distally to the syringe body, the first liquid is first discharged from the distal chamber through the needle, and then, continuously, the second liquid is discharged from the proximal chamber through the needle.

101. The system according to claim 100, wherein the distal portion includes a sharp distal end.

102. The system according to claim 100, wherein the proximal portion and the intermediate connection portion have substantially equal diameters to each other.

103. The aforementioned proximal portion includes a solid proximal end feature, The system according to claim 100, wherein the intermediate connector comprises a tubular member.

104. The system according to claim 103, wherein the solid proximal end feature portion is cold-formed.

105. The system according to claim 103, wherein the distal end of the solid proximal end feature portion is located within the proximal end of the tubular member.

106. The system according to claim 103, wherein the proximal portion defines a longitudinal channel on its surface.

107. The system according to claim 106, wherein the length of the longitudinal channel is substantially equal to the length of the distal stopper member, and as a result, when the distal stopper member is inserted into the distal end of the syringe body, the proximal stopper member is inserted distal to the needle, and the proximal end of the longitudinal channel is positioned within the proximal chamber.

108. The system according to claim 106, wherein the proximal stopper member, the distal stopper member, and the syringe body are configured such that a distal force applied to the proximal stopper member is transmitted to the distal stopper member through the second liquid until the proximal stopper member is inserted distally to the needle and the proximal opening is positioned within the proximal chamber.

109. The system according to claim 106, wherein the length of the longitudinal channel provides an allowable range for variations related to the proximal stopper member and / or the distal stopper member.

110. The system according to claim 109, wherein the fluctuation relating to the proximal stopper member and / or the distal stopper member is selected from the group consisting of the strain on the proximal surface of the distal stopper member, the position of the proximal stopper member with respect to the longitudinal channel, and the position of the distal stopper member with respect to the longitudinal channel.

111. The system according to claim 106, wherein the distance between the longitudinal channel and the solid proximal end minimizes backflow leakage of the first liquid and the second liquid to the plunger.

112. The system according to claim 106, wherein the longitudinal channel is formed by stamping or injection molding.

113. The aforementioned system, A first injection configuration in which the proximal end of the longitudinal channel is positioned within the distal chamber or the distal stopper member, The system according to claim 106, further comprising a second injection configuration in which the proximal end of the longitudinal channel is positioned within the proximal chamber, thereby enabling the second liquid to be transferred from the proximal chamber through the longitudinal channel out of the distal end opening of the distal portion of the needle assembly.

114. The system according to claim 100, wherein the first and second sizes of the respective distal chamber and proximal chamber can be changed by moving the proximal stopper member and the distal stopper member relative to the syringe body.

115. Hub and, The needle hub assembly further comprises a needle retaining member configured to removably connect the needle to the hub, The plunger member is The needle retention feature section located inside the plunger, An energy storage member is disposed inside the plunger, The plunger comprises an energy storage member latch member located inside the plunger, The system according to claim 100, wherein the needle is at least partially retractable into the plunger when the plunger member is operated relative to the syringe body to convert the energy storage member latch member from a latched state to an unlatched state.

116. The system according to claim 115, wherein the needle is configured to completely puncture at least the distal stopper member so as to be at least partially drawn into the plunger.

117. The system according to claim 115, wherein the energy storage member latch member is configured to convert from the latched state to the non-latched state, which at least partially retracts the needle into the plunger after the second liquid has been discharged from the proximal chamber through the needle.

118. The system according to claim 115, wherein the needle retention feature is configured to activate the conversion of the energy storage member latch member from the latched state to the unlatched state when the plunger member is operated to insert the proximal stopper member into the distal end of the syringe body.

119. The system according to claim 100, wherein the proximal stopper member and the distal stopper member each include a first polymer coating and a second polymer coating on their respective distal and proximal surfaces, and as a result the proximal chamber is defined by the syringe body and the first polymer coating and the second polymer coating.

120. A system for continuously injecting liquids, A syringe body that defines the proximal opening of the syringe and the distal needle interface at its distal end, A proximal stopper member and a distal stopper member disposed within the syringe body, wherein a proximal chamber is formed between the proximal stopper member and the distal stopper member, and a distal chamber is formed between the distal stopper member and the distal end of the syringe body, The first liquid in the distal chamber, The second liquid in the proximal chamber, A plunger is configured to be manually operated to insert the proximal stopper member distally to the syringe body, Proximal portion, and A fluid transfer assembly comprising an intermediate connector, The proximal portion has longitudinal channels formed on the surface, The intermediate connector has a distal anchor member, A system in which, by operating the plunger member to insert the proximal stopper member distally to the syringe body, the first liquid is first discharged from the distal chamber through the needle, and then, continuously, the second liquid is discharged from the proximal chamber through the needle.

121. The aforementioned proximal portion is a solid metal elongated body. The system according to claim 120, wherein the intermediate connector is a polymer body having a recess configured to receive the distal end of the proximal portion.

122. The system according to claim 120, wherein the fluid transfer assembly is molded from a polymer as a single piece.

123. The system according to claim 120, wherein the fluid transfer assembly is formed from metal as a single piece.

124. The system according to claim 120, wherein the distal anchor member has a rectangular cross-sectional shape.

125. The distal anchor member comprises a slot having a biasing member disposed inside, The system according to claim 120, wherein the biasing member is configured to apply a radially outward force to the inner wall of the distal needle interface.

126. The system according to claim 120, wherein the distal anchor member includes a corrugated wire-like member configured to apply a radially outward force to the inner wall of the distal needle interface.

127. The system according to claim 120, wherein the distal anchor member includes a pair of flexible arms configured to apply a radially outward force to the inner wall of the distal needle interface.

128. The system according to claim 120, wherein the distal anchor member includes a rubber sleeve configured to increase friction between the distal anchor member and the inner wall of the distal needle interface.

129. The system according to claim 128, wherein the distal anchor member further comprises a proximal opening and a distal opening configured to bypass the rubber sleeve.

130. A system for continuously injecting liquids, A syringe body that defines the proximal opening of the syringe and the distal needle interface at its distal end, A proximal stopper member and a distal stopper member disposed within the syringe body, wherein a proximal chamber is formed between the proximal stopper member and the distal stopper member, and a distal chamber is formed between the distal stopper member and the distal end of the syringe body, The first liquid in the distal chamber, The second liquid in the proximal chamber, A plunger is configured to be manually operated to insert the proximal stopper member distally to the syringe body, Proximal portion, and A fluid transfer assembly comprising an intermediate connector, The intermediate connector has a distal anchor member, A system in which, by operating the plunger member to insert the proximal stopper member distally to the syringe body, the first liquid is first discharged from the distal chamber through the needle, and then, continuously, the second liquid is discharged from the proximal chamber through the needle.

131. The aforementioned proximal portion is defined by a plurality of arms, with their distal ends being: The system according to claim 130, wherein the intermediate connector is a polymer body having an opening configured to receive the arm of the proximal portion.

132. The system according to claim 131, wherein the plurality of arms are tapered radially outward and their proximal portions are connected to the intermediate connector.

133. The system according to claim 132, wherein the plurality of arms are tapered radially outward and apply a radially outward force to the inner wall of the distal needle interface.

134. The distal anchor member comprises a slot having a biasing member disposed inside, The distal anchor member defines a pair of bumps within the slot, The biasing member defines a pair of notches configured to receive the pair of bumps, The system according to claim 130, wherein the biasing member is configured to apply a radially outward force to the inner wall of the distal needle interface.

135. The system according to claim 130, wherein the proximal portion has longitudinal channels formed on its surface.

136. A system for continuously injecting liquids, A syringe body that defines the proximal opening of the syringe and the distal needle interface at its distal end, A proximal stopper member and a distal stopper member disposed within the syringe body, wherein a proximal chamber is formed between the proximal stopper member and the distal stopper member, and a distal chamber is formed between the distal stopper member and the distal end of the syringe body, The powdered drug component in the distal chamber, The liquid drug component in the proximal chamber, A plunger is configured to be manually operated to insert the proximal stopper member distally to the syringe body, Proximal section, Intermediate connector, and A needle assembly having a distal portion, A system comprising a one-way valve partially located within the distal needle interface and configured to minimize the transfer of the powdered drug component from the distal chamber into the needle assembly.

137. By operating the plunger member to insert the proximal stopper member distal to the syringe body by a first distance, the liquid drug component is transferred from the proximal chamber to the distal chamber, forming a mixed liquid drug with the powdered drug component. The system according to claim 136, wherein the plunger member is operated to insert the proximal stopper member distally by a second distance relative to the syringe body, thereby causing the mixed liquid drug to be discharged from the distal chamber and pass through the one-way valve and the needle assembly.

138. The system according to claim 136, wherein the distal portion includes a sharp distal end.

139. The system according to claim 136, further comprising a needle retraction system disposed within the plunger member and configured to retract the needle assembly at least partially into the plunger member after injection.

140. The aforementioned one-way valve comprises a proximal valve portion and a distal valve portion, The system according to claim 136, wherein the proximal valve portion includes a sleeve extending distally from its center.

141. The system according to claim 140, wherein the sleeve is configured to have a strict tolerance between the sleeve and the distal valve portion of the needle assembly through which it passes, so that powdered drug components cannot pass between the sleeve and the distal valve portion of the needle assembly.

142. The system according to claim 141, wherein the strict tolerance allows the liquid drug to pass under pressure between the sleeve and the distal valve portion of the needle assembly.

143. The system according to claim 140, wherein the sleeve defines a plurality of longitudinal channels on its surface.

144. The proximal valve portion of the aforementioned one-way valve defines an opening through which it passes, The system according to claim 143, wherein when a liquid drug is under pressure in the distal chamber, a liquid flow path is formed from the distal chamber through the opening, along the longitudinal channel between the proximal and distal valve portions of the one-way valve, through the needle assembly, to the outside of the system.

145. The system according to claim 140, wherein the proximal valve portion and the distal valve portion of the one-way valve are configured to have strict tolerances from each other so that powdered drug components cannot pass between the proximal valve portion and the distal valve portion of the one-way valve.

146. The system according to claim 145, wherein the strict tolerance allows the liquid drug to pass under pressure between the proximal valve portion and the distal valve portion of the one-way valve.

147. The system according to claim 140, wherein the proximal valve portion is rigid and the distal valve portion is flexible.

148. The system according to claim 147, wherein when a liquid drug is under pressure in the distal chamber, at least a portion of the distal valve portion bends away from the proximal valve portion.

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