Apparatus, system, and method for medical device adapters

Abstract

The present embodiments generally relate to apparatus, systems, and methods for deploying a medical device to the skin of a host. The medical device may include a transcutaneous analyte sensor applied to the skin of the host. The apparatus, systems, and methods may include at least a portion of an on-skin medical device and an adapter body for interfacing with an applicator of the on-skin medical device.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 436,527, filed December 31, 2022, the entire contents of which are incorporated herein by reference.

[0002] FIELD OF THE INVENTION Medical Device Apparatus, Systems, and Methods More specifically, apparatus, systems, and methods are provided for a medical device adapter that may include a transcutaneous analyte sensor for deployment in the skin of a host. [Background technology]

[0003] Description of Related Art Diabetes mellitus is a disorder in which the pancreas cannot make enough insulin (type 1, or insulin-dependent), and / or insulin is not effective (type 2, or non-insulin-dependent). In the diabetic state, the victim suffers from hyperglycemia, which can lead to a number of physiological disorders associated with deterioration of small blood vessels, such as kidney failure, skin ulcers, or bleeding into the vitreous of the eye. A hypoglycemic reaction (hypoglycemia) can be precipitated by inadvertent overdosing of insulin or after normal administration of insulin or glucose-lowering agents accompanied by abnormal exercise or inadequate food intake.

[0004] Traditionally, people with diabetes carry self-monitoring blood glucose (SMBG) monitors, which typically require an uncomfortable finger-prick method. Due to a lack of comfort and convenience, people with diabetes typically measure their glucose levels only two to four times per day. Unfortunately, these time intervals are spread so far apart that people with diabetes may not know about their hyperglycemic or hypoglycemic condition until it is too late, sometimes resulting in dangerous side effects. Alternatively, glucose levels can be continuously monitored by a measurement system including an on-skin sensor assembly. The sensor assembly may have a wireless transmitter that transmits measurement data to a receiver, which can process and display information based on the measurements.

[0005] The applicator may be utilized to deploy the on-skin sensor assembly to a person. The application process should result in the on-skin sensor assembly being attached to the person, with the on-skin sensor assembly being capable of sensing analyte (e.g., glucose) level information, communicating the sensed data to the transmitter, and transmitting the analyte level information to a receiver.

[0006] Exemplary systems are disclosed, for example, in US Pat. Nos. 5,629,399; 5,729,4 ... and 5,829,530, which are owned by the assignee of the present application and are incorporated herein by reference in their entireties.

[0007] This Background is provided to introduce a brief background to the Summary and Detailed Description that follow. This Background is not intended to aid in determining the scope of the claimed subject matter, nor should it be deemed to limit the claimed subject matter to implementations that solve any or all of the disadvantages or problems presented above. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] US Patent Application Publication No. 2014 / 0088389 [Patent Document 2] US Patent Application Publication No. 2013 / 0267813 [Patent Document 3] US Patent Application Publication No. 2018 / 0368771 [Patent Document 4] US Patent Application Publication No. 2011 / 0027127 [Patent Document 5] U.S. Patent No. 6,565,509 [Patent Document 6] U.S. Patent No. 6,579,690 [Patent Document 7] U.S. Patent No. 6,484,046 [Patent Document 8] US Patent Application Publication No. 2005 / 0203360 [Patent Document 9] US Patent Application Publication No. 2009 / 0192745 [Patent Document 10] US Patent Application Publication No. 2009 / 0240120 [Patent Document 11] US Patent Application Publication No. 2012 / 0078071 [Patent Document 12] U.S. Patent No. 7,310,544 [Patent Document 13] US Patent Application Publication No. 2007 / 0032706 [Patent Document 14] U.S. Patent No. 6,931,327 [Patent Document 15] US Patent Application Publication No. 2005 / 0043598 [Patent Document 16] US Patent Application Publication No. 2007 / 0016381 [Patent Document 17] US Patent Application Publication No. 2008 / 0033254 [Patent Document 18] US Patent Application Publication No. 2005 / 0154271 [Patent Document 19] US Patent Application Publication No. 2005 / 0192557 [Patent Document 20] US Patent Application Publication No. 2006 / 0222566 [Patent Document 21] US Patent Application Publication No. 2007 / 0203966 [Patent Document 22] US Patent Application Publication No. 2007 / 0208245 [Patent Document 23] U.S. Patent No. 7,497,827 [Patent Document 24] U.S. Patent No. 8,828,201 [Patent Document 25] U.S. Patent No. 1,121,9413 [Patent Document 26] US Patent Application Publication No. 2019 / 0342637 Summary of the Invention

[0009] The present systems and methods relate to apparatus, systems, and methods for medical devices. More specifically, apparatus, systems, and methods are provided for a medical device adapter that may include a transcutaneous analyte sensor for deployment to the skin of a host. Various embodiments of the present apparatus, systems, and methods may have several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of the present embodiments as expressed by the claims that follow, their more prominent features will now be briefly discussed. After considering this discussion, and particularly after reading the section entitled "Detailed Description of the Invention," one will understand how the features of the present embodiments provide the advantages described herein.

[0010] In a first aspect, an apparatus comprises an adapter body configured to interface between at least a portion of an on-skin medical device and an applicator of the on-skin medical device.

[0011] Implementations of the embodiments may include one or more of the following: The adapter body may be configured to interface between at least a portion of the on-skin wearable medical device having a first configuration and a portion of the applicator configured to engage a second configuration of at least a portion of the on-skin wearable medical device that is different from the first configuration. The second configuration differs from the first configuration in one or more of shape or size. The portion having at least the first configuration may be a first on-skin wearable medical device, and the on-skin wearable medical device having at least a portion having the second configuration is a second on-skin wearable medical device, where the first configuration includes a configuration of a first wearable housing of the first on-skin wearable medical device and the second configuration includes a configuration of a second wearable housing of the second on-skin wearable medical device. The on-skin wearable medical device having at least a portion having the first configuration may be the same as the on-skin wearable medical device having at least a portion having the second configuration. The on-skin medical device may be a first on-skin medical device, and the adapter body may be configured to interface with a wearable housing of the first on-skin medical device that is smaller than the wearable housing of a second on-skin medical device configured to engage with the applicator. The wearable housing of the first on-skin medical device may have a smaller diameter or height than the wearable housing of the second on-skin medical device. The adapter body may be configured to accommodate at least a portion of the on-skin medical device to fit into an engagement portion of the applicator. The adapter body may include a holding area for receiving at least a portion of the on-skin medical device. The adapter body may include a cavity for receiving at least a portion of the on-skin medical device. The adapter body may include one or more walls that define a holding area for receiving at least a portion of the on-skin medical device. The one or more walls may include one or more side walls that define a holding area. The one or more side walls can include an inner surface and an outer surface, the inner surface configured to face a portion of the on-skin medical device and the outer surface configured to face the opposite side from the inner surface.The one or more side walls may have a gap between their inner and outer surfaces configured to space the outer surface of the on-skin medical device from the outer surface of the one or more side walls. The gap may be configured to accommodate at least a portion of the on-skin medical device to fit into an engagement portion of an applicator. The inner surface of the one or more side walls may form an inner circumference having a contour different from the outer circumference formed by the outer surface of the one or more side walls. The inner surface of the one or more side walls may form an inner circumference having a diameter smaller than the outer circumference formed by the outer surface of the one or more side walls. The one or more walls may include an upper wall that defines a holding area. The upper wall may include an inner surface and an outer surface, the inner surface configured to face a portion of the on-skin medical device and the outer surface configured to face the opposite side from the inner surface. The upper wall may have a gap between its inner and outer surfaces configured to space the outer surface of the on-skin medical device from the outer surface of the upper wall. The gap may be configured to accommodate at least a portion of the on-skin medical device to fit into an engagement portion of an applicator. The one or more stabilizers may be for stabilizing at least a portion of the on-skin-wearable medical device within the holding area. The one or more stabilizers may include one or more protrusions for contacting at least a portion of the on-skin-wearable medical device. The adapter body may include a ring extending around the holding area for receiving at least a portion of the on-skin-wearable medical device. The adapter body may include a retaining portion for holding at least a portion of the on-skin-wearable medical device to the adapter body. The one or more device couplers may be for coupling the on-skin-wearable medical device to the adapter body. The one or more device couplers may include an adhesive. The one or more device couplers may include one or more protrusions or recesses configured to engage with at least a portion of the on-skin-wearable medical device. The one or more device couplers may be configured to deflect. The one or more device couplers may include a releasable coupler configured to release the on-skin-wearable medical device from the adapter body. The one or more device couplers may include one or more arms. The one or more arms may define a boundary of the holding area for receiving at least a portion of the on-skin-wearable medical device.The one or more arms may be configured to bend radially outward from the holding region to receive at least a portion of the on-skin medical device. The adapter body may include one or more support portions configured to support the one or more device couplers in a coupled configuration with at least a portion of the on-skin medical device. The one or more support portions may include one or more contact surfaces of the adapter body. The one or more support portions may include one or more hooks. The one or more applicator couplers may be for coupling the adapter body to at least a portion of the applicator. The one or more applicator couplers may include one or more protrusions or recesses configured to engage with at least a portion of the applicator. The adapter body may include an ejection portion configured to eject at least a portion of the on-skin medical device from the adapter body. The ejection portion may include one or more openings in a surface of the adapter body. The on-skin medical device may include a transcutaneous analyte sensor, and the adapter body is configured to be disposed within a housing of the applicator. The adapter body may include an actuation body configured to electrically activate the on-skin medical device. The actuation body may include a magnet. The adapter body may include one or more walls defining a holding area for receiving at least a portion of the on-skin medical device, the actuation body being disposed on at least one of the one or more walls. The one or more walls may include a top wall defining the holding area, the actuation body being disposed on the top wall.

[0012] In a second aspect, the system includes an applicator of an on-skin medical device and an adapter body configured to interface between at least a portion of the on-skin medical device and the applicator of the on-skin medical device.

[0013] Implementations of the embodiments may include one or more of the following: The applicator may include an engagement portion configured to engage with the adapter body. The engagement portion may be configured to engage an outer surface of the adapter body. The on-skin wearable medical device is a first on-skin wearable medical device, and the engagement portion is configured to engage with a second on-skin wearable medical device having a different configuration from the first on-skin wearable medical device. The first on-skin wearable medical device may have a wearable housing having a smaller diameter or height than the wearable housing of the second on-skin wearable medical device. The on-skin wearable medical device may be a first on-skin wearable medical device having a first wearable housing, and the engagement portion is sized to fit into a second wearable housing of the second on-skin wearable medical device, and the second wearable housing has a larger diameter or height than the first wearable housing. The adapter body may be configured to adapt at least a portion of the on-skin wearable medical device to fit into the engagement portion of the applicator. The adapter body may include a holding area for receiving at least a portion of the on-skin medical device. The adapter body may include a cavity for receiving at least a portion of the on-skin medical device. The adapter body may include one or more walls defining a boundary of the holding area for receiving at least a portion of the on-skin medical device. The applicator may include an engaging portion configured to engage with at least a portion of the one or more walls. The adapter body may include one or more device couplers for coupling the on-skin medical device to the adapter body. The one or more device couplers may include releasable couplers configured to release the on-skin medical device from the adapter body. The adapter body may include one or more support portions configured to support the one or more device couplers in a coupled configuration with at least a portion of the on-skin medical device, and the applicator may include one or more contact surfaces configured to abut the one or more support portions. The one or more support portions may include one or more hooks.The one or more contact surfaces include at least one post configured to engage with one or more hooks, the at least one post configured to be withdrawn from the one or more hooks to separate the one or more device couplers from at least a portion of the on-skin-wearable medical device. The applicator may be configured such that the at least one post is withdrawn during needle retraction to guide the transcutaneous analyte sensor into the skin of the host. The adapter body may include an ejection portion configured to eject at least a portion of the on-skin-wearable medical device from the adapter body, and the applicator includes an ejection actuator configured to eject the on-skin-wearable medical device from the adapter body. The on-skin-wearable medical device may include a mating mismatch with the applicator. The on-skin-wearable medical device may have a wearable housing having a configuration different from the configuration of the wearable housing with which the engaging portion of the applicator is configured to mate. The wearable housing of the on-skin-wearable medical device may have a smaller diameter or height than the configuration of the wearable housing with which the engaging portion of the applicator is configured to mate. The on-skin-wearable medical device may include a transcutaneous analyte sensor. The adapter body may include an actuation body for electrically actuating the on-skin medical device. The actuation body may include a magnet.

[0014] In a third aspect, a method includes utilizing an applicator to apply a skin-mountable medical device to the skin of a host, with an adapter body interfacing between at least a portion of the skin-mountable medical device and the applicator.

[0015] Implementations of embodiments may include one or more of the following: The on-skin wearable medical device may include a mating mismatch with the applicator. The adapter body may adapt at least a portion of the on-skin wearable medical device to fit into an engagement portion of the applicator. The on-skin wearable medical device is a first on-skin wearable medical device, and the applicator has an engagement portion configured to engage with a second on-skin wearable medical device having a different configuration from the first on-skin wearable medical device. The engagement portion may be configured to engage with a wearable housing of the second on-skin wearable medical device having a larger diameter or height than the wearable housing of the first on-skin wearable medical device. The method may include releasing the on-skin wearable medical device from the adapter body. The method may include utilizing one or more releasable couplers to release the on-skin wearable medical device from the adapter body. The method may include retaining the adapter body on the applicator following release of the on-skin wearable medical device from the adapter body. The on-skin wearable medical device may include a transcutaneous analyte sensor. The method may include guiding the transcutaneous analyte sensor into the host's skin using an insertion element of the applicator. The method may further include electrically activating the on-skin wearable medical device using an actuation body disposed on the adapter body. The actuation body may include a magnet. Electrically activating the on-skin wearable medical device may include activating the on-skin wearable medical device from a low power state to a high power state. Electrically activating the on-skin wearable medical device may include increasing the distance between the on-skin wearable medical device and the actuation body. The adapter body may include one or more walls defining a holding area for receiving at least a portion of the on-skin wearable medical device, and the actuation body is disposed on at least one of the one or more walls.

[0016] In further aspects and embodiments, the features of the above-described methods and various aspects are formulated with respect to a system, as in the various aspects, having an applicator configured to perform the method features. Any of the features of an embodiment of any of the aspects, including but not limited to any embodiment of any of the first through third aspects mentioned above, is applicable to all other aspects and embodiments identified herein, including but not limited to any embodiment of any of the first through third aspects mentioned above. Furthermore, any of the features of the embodiments of the various aspects, including but not limited to any embodiment of any of the first through third aspects mentioned above, can be independently combined in any manner, partially or wholly, with other embodiments described herein; for example, one, two, or more embodiments may be combined in whole or in part. Furthermore, any of the features of the embodiments of the various aspects, including but not limited to any embodiment of any of the first through third aspects mentioned above, can be optional with respect to other aspects or embodiments. Any aspect or embodiment of the method may be performed by a system or apparatus of another aspect or embodiment, and any aspect or embodiment of the system or apparatus may be configured to perform the method of another aspect or embodiment, including but not limited to any embodiment of any of the first to third aspects referred to above.

[0017] This Summary is provided to introduce a selection of concepts in a simplified form. The concepts are further described in the Detailed Description. Elements or steps other than those described in this Summary are possible, and no element or step is necessarily required. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended for use as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all of the disadvantages noted in any part of this disclosure.

[0018] These and other features, aspects, and advantages are described below with reference to the drawings, which are intended to illustrate, but not limit, the disclosure, in which like reference characters indicate corresponding features consistently throughout like embodiments. [Brief explanation of the drawings]

[0019] [Figure 1] 1 shows a schematic diagram of a continuous analyte sensor system. [Figure 2A] FIG. 1 shows a top assembled perspective view of an on-skin sensor assembly. [Figure 2B] FIG. 2B shows a bottom perspective view of the assembled on-skin sensor assembly of FIG. 2A. [Figure 2C] FIG. 2B shows a top perspective view of the on-skin sensor assembly of FIG. 2A in an assembled state. [Figure 3] FIG. 1 shows an assembled perspective view of an on-skin sensor assembly. [Figure 4] FIG. 1 shows a perspective view of an on-skin sensor assembly. [Figure 5] FIG. 1 illustrates a perspective view of an applicator system for an on-skin sensor assembly of an analyte sensor system. [Figure 6] 6 shows an exploded perspective view of the applicator system of FIG. 5. [Figure 7] 5 and 6 along section line A-A' in FIG. 5, showing several cross-sectional views of the applicator system of FIGS. [Figure 8] 5 and 6 along section line A-A' in FIG. 5, showing several cross-sectional views of the applicator system of FIGS. [Figure 9] 5 and 6 along section line A-A' in FIG. 5, showing several cross-sectional views of the applicator system of FIGS. [Figure 10] 5 and 6, taken along section line BB' of FIG. 5, in operation. [Figure 11] 5 and 6, taken along section line BB' of FIG. 5, in operation. [Figure 12] 5 and 6, taken along section line BB' of FIG. 5, in operation. [Figure 13] 7 shows an enlarged view of some features of the applicator system of FIGS. 5 and 6. FIG. [Figure 14] 7 shows an enlarged view of some features of the applicator system of FIGS. 5 and 6. FIG. [Figure 15] 7 shows an enlarged view of some features of the applicator system of FIGS. 5 and 6. FIG. [Figure 16] 7 shows an enlarged view of some features of the applicator system of FIGS. 5 and 6. FIG. [Figure 17] FIG. 7 shows a perspective partial cutaway view of the needle carrier assembly, hub, and on-skin sensor assembly of the applicator system of FIGS. 5 and 6. [Figure 18] FIG. 7 shows a cross-sectional view of the hub and on-skin sensor assembly of the applicator system of FIGS. 5 and 6. [Figure 19] FIG. 7 shows a top view of a portion of the needle carrier assembly and hub of FIGS. 5 and 6. [Figure 20A] 10A-10C show perspective views of a locking feature for a needle for use in an applicator for an analyte sensor system. [Figure 20B] 10A-10C show perspective views of a locking feature for a needle for use in an applicator for an analyte sensor system. [Figure 21] 10A-10C illustrate several cross-sectional views of yet another applicator for an on-skin sensor assembly of an analyte sensor system, showing various features and operating positions. [Figure 22] 10A-10C illustrate several cross-sectional views of yet another applicator for an on-skin sensor assembly of an analyte sensor system, showing various features and operating positions. [Figure 23] 10A-10C illustrate several cross-sectional views of yet another applicator for an on-skin sensor assembly of an analyte sensor system, showing various features and operating positions. [Figure 24] 24A-24D show perspective views of various features of the applicator system of FIGS. 21-23. [Figure 25] 1 illustrates a cross-sectional view of a system, according to some embodiments. [Figure 26A] 1A-1C show cross-sectional schematic views of an analyte sensor with and without an insert element. [Figure 26B] 1A-1C show cross-sectional schematic views of an analyte sensor with and without an insert element. [Figure 27] FIG. 1 shows a perspective view of the housing of the on-skin sensor assembly. [Figure 28] FIG. 1 shows a perspective view of the housing of the on-skin sensor assembly. [Figure 29A] FIG. 2 shows a top perspective view of the adapter. [Figure 29B] 29B shows a bottom perspective view of the adapter shown in FIG. 29A. [Figure 29C] 29B shows a top view of the adapter shown in FIG. 29A placed on an on-skin sensor assembly. [Figure 30A] 29B shows a perspective view of the adapter shown in FIG. 29A coupled to an applicator. [Figure 30B] 29B shows a perspective view of the adapter shown in FIG. 29A coupled to an applicator and coupled to an on-skin sensor assembly. [Figure 30C] 1 shows a detailed perspective view of the device coupler of the adapter. [Figure 30D] FIG. 30C shows a perspective view of the proximal movement of the adapter and on-skin sensor assembly shown in FIG. 30B. [Figure 30E] 13A shows a perspective view of the retraction of the engagement portion of the applicator. FIG. [Figure 30F] 30B shows a perspective view of the adapter shown in FIG. 30A with the on-skin sensor assembly released from the adapter. [Figure 30G] 29B shows a detailed perspective view of the applicator coupler of the adapter shown in FIG. 29A. [Figure 31A] 1 shows a plan view of the adapter. [Figure 31B] FIG. 31B shows a top view of the adapter shown in FIG. 31A placed on an on-skin sensor assembly. [Figure 31C]FIG. 31B shows a bottom view of the adapter shown in FIG. 31A placed on an on-skin sensor assembly. [Figure 31D] FIG. 31B shows a top view of the adapter shown in FIG. 31A placed on an on-skin sensor assembly with the device coupler in a closed position. [Figure 31E] FIG. 31B shows a bottom view of the adapter shown in FIG. 31A placed on an on-skin sensor assembly with the device coupler in a closed position. [Figure 32A] FIG. 31B illustrates an end view of the adapter shown in FIG. 31A positioned on an on-skin sensor assembly and coupled to an applicator. [Figure 32B] 31B shows a perspective view of the adapter shown in FIG. 31A coupled to an applicator. [Figure 32C] 13A shows an end view of the retraction of the engagement portion of the applicator. FIG. [Figure 32D] FIG. 13 shows a detailed perspective view of the release of the device coupler from the on-skin sensor assembly. [Figure 32E] FIG. 31B shows an end view of the on-skin sensor assembly released from the adapter shown in FIG. 31A. [Figure 33A] FIG. 10 shows a top view of the adapter positioned on the on-skin sensor assembly. [Figure 33B] FIG. 33B shows a bottom view of the adapter shown in FIG. 33A positioned on the on-skin sensor assembly. [Figure 33C] FIG. 33B shows a bottom view of the adapter shown in FIG. 33A separated from the on-skin sensor assembly. [Figure 34A] 33B shows a perspective view of the adapter shown in FIG. 33A coupled to an applicator. [Figure 34B] FIG. 33C shows a perspective view of the proximal movement of the adapter and on-skin sensor assembly shown in FIG. 33B. [Figure 34C] FIG. 33B shows a perspective view of the adapter shown in FIG. 33A with the on-skin sensor assembly released from the adapter. [Figure 34D] FIG. 34B shows a side cross-sectional view of the adapter shown in FIG. 34A coupled to an on-skin sensor assembly and positioned within an applicator. [Figure 34E] 34B shows a side cross-sectional view of the adapter shown in FIG. 34A positioned within an applicator. [Figure 34F] 1 shows a perspective view of a portion of the applicator. [Figure 35A] 1 shows a plan view of the adapter. [Figure 35B] FIG. 35B shows a bottom perspective view of the adapter shown in FIG. 35A. [Figure 35C] FIG. 35B shows a top view of the adapter shown in FIG. 35A placed on an on-skin sensor assembly. [Figure 35D] FIG. 35B shows a bottom view of the adapter shown in FIG. 35A placed on an on-skin sensor assembly. [Figure 35E] FIG. 35B shows a bottom view of the adapter shown in FIG. 35A positioned on an on-skin sensor assembly and coupled to an applicator. [Figure 35F] FIG. 35B shows a perspective view of the adapter shown in FIG. 35A positioned on an on-skin sensor assembly and coupled to an applicator. [Figure 35G] 35B shows a detailed perspective view of the contact surface of the applicator that contacts the support portion of the adapter shown in FIG. 35A. [Figure 36A] FIG. [Figure 36B] FIG. 1 shows a perspective view of an on-skin sensor assembly. [Figure 36C] 36B within the holding area of ​​the adapter shown in FIG. 36A. FIG. [Figure 37] 36D shows a cross-sectional view of the on-skin sensor assembly within the holding area of ​​the adapter along line CC' in FIG. 36C. [Figure 38] FIG. 10 shows a perspective view of the engagement portion of the applicator. [Figure 39A] 36B shows a cross-sectional view of an engagement portion of an applicator coupled to the adapter shown in FIG. 36A. [Figure 39B] 36B shows a cross-sectional view of the engagement portion of the applicator released from the adapter shown in FIG. 36A. [Figure 39C]36B shows a cross-sectional view of the adapter shown in FIG. 36A released from the on-skin sensor assembly. [Figure 40] FIG. 10 shows a perspective view of the adapter body shown with an on-skin sensor assembly. [Figure 41] 41 shows a cross-sectional side view of the adapter body and on-skin sensor assembly shown in FIG. 40 taken along line DD' in FIG. 40. DETAILED DESCRIPTION OF THE INVENTION

[0020] The following description illustrates in detail several embodiments of the present disclosure. Those skilled in the art will recognize that there are many variations and modifications of the present disclosure that are encompassed by the scope of the present disclosure. Therefore, the description of a particular embodiment should not be considered as limiting the scope of the present disclosure.

[0021] 1 illustrates an exemplary medical device system according to embodiments herein. In some embodiments, the medical device system may include a continuous analyte monitoring system 100. The continuous analyte monitoring system 100 may include an analyte sensor system 102 that includes an on-skin sensor assembly 160 configured to be secured to the skin of a host via a base (not shown).

[0022] In embodiments, other forms of medical device systems may be utilized, including other forms of monitoring systems, drug delivery systems, or other treatment systems. In embodiments, on-skin medical devices may be utilized, which may include on-skin sensor assemblies or drug delivery medical devices, among other forms of on-skin medical devices.

[0023] As shown in FIG. 1 , the analyte sensor system 102 can be operatively connected to a host and multiple display devices 110-114 according to certain aspects of the present disclosure. Exemplary display devices 110-114 can include computers such as smartphones, smartwatches, tablet computers, laptop computers, and desktop computers. In some examples, the display devices 110-114 can be Apple Watch, iPhone®, and iPad® manufactured by Apple Inc., or iOS, Windows®, or Android® operating system devices. Note that the display device 114 can alternatively or additionally be a display device and a drug delivery device capable of cooperatively operating with the analyte sensor system 102 to deliver a drug to the host. The analyte sensor system 102 can include a sensor electronics module 140 and a continuous analyte sensor 138 associated with the sensor electronics module 140. The sensor electronics module 140 can communicate directly and wirelessly with one or more of the multiple display devices 110-114 via wireless communication signals. As discussed in more detail below, the display devices 110-114 may also communicate among one another and / or through one another to the analyte sensor system 102. For ease of reference, wireless communication signals from the analyte sensor system 102 to the display devices 110-114 may be referred to as “uplink” signals 128. For example, wireless communication signals from the display devices 110-114 to the analyte sensor system 102 may be referred to as “downlink” signals 130. Wireless communication signals between two or more of the display devices 110-114 may be referred to as “crosslink” signals 132. Additionally, wireless communication signals may include data transmitted by one or more of the display devices 110-113 to one or more remote servers 190, or network entities such as cloud-based servers or databases, via “long-range” uplink signals 136 (e.g., cellular signals), and may receive long-range downlink signals 142 transmitted by the remote servers 190.

[0024] 1 , one of the display devices may be a custom display device 111 specifically designed to display a particular type of displayable sensor information (e.g., in some embodiments, numbers and arrows) associated with the analyte value received from the sensor electronics module 140. In some embodiments, one of the display devices may be a handheld device 112, such as a mobile phone, palmtop computer, or the like based on the Android operating system, iOS operating system, or other operating system, which may have a relatively large display and be configured to display a graphical representation of continuous sensor data (e.g., including current and historical data). Other display devices may include a tablet 113, a smartwatch 110, a medication delivery device 114, a blood glucose meter, and / or other handheld devices such as a desktop or laptop computer.

[0025] In the case of the display device 114, which may be a drug delivery device in addition to or instead of a display device, it will be understood that the alert and / or sensor information provided by the continuous analyte sensor 138 to the sensor electronics module 140 may be used to initiate and / or adjust the delivery of the drug to the host.

[0026] During use, the sensing portion of sensor 138 may be disposed under the skin of a host, and the contact portion of sensor 138 may be electrically connected to sensor electronics module 140. The electronics module 140 may be engaged with a housing (e.g., a base) that is attached to a patch that may engage with the skin of the host. The housing may include a wearable housing. The patch, in embodiments, may be an adhesive patch. In some embodiments, the electronics module 140 is integrally formed with the housing. Furthermore, the electronics module 140 may be disposable and may be directly coupled to the patch.

[0027] The continuous analyte sensor system 100 can include a sensor arrangement that provides an output signal indicative of an analyte concentration. The output signal, which includes sensor data (e.g., a raw data stream, filtered data, smoothed data, and / or otherwise transformed sensor data), is transmitted to a receiver.

[0028] In some examples, the analyte sensor system 102 includes a transcutaneous glucose sensor such as that described in U.S. Patent No. 6,279,629, the entire contents of which are incorporated herein by reference. In some examples, the sensor system 102 includes a continuous glucose sensor and comprises a transcutaneous sensor (e.g., as described in U.S. Patent No. 6,279,629, the entire contents of which are incorporated herein by reference).

[0029] Examples of various signal processing techniques and glucose monitoring systems suitable for use with the embodiments described herein are described in U.S. Patent Nos. 6,275,999 and 6,329,263, the contents of which are incorporated herein by reference in their entireties. The sensor can extend through a housing, which can maintain the sensor 138 on, in, or under the skin and / or provide an electrical connection of the sensor 138 to the sensor electronics in the sensor electronics module 140.

[0030] In some embodiments, descriptions of the base, housing, garment, and / or transmitter of on-skin sensor assembly 160 may be interchangeable. In other embodiments, the base and housing of on-skin sensor assembly 160 may differ from the sensor electronics module 140 in the sense that they may be separate components from the transmitter or receiver, for example.

[0031] In some embodiments, the sensor 138 is in the form of a wire. The distal end of the wire can be formed, for example, with a conical shape (to facilitate insertion of the wire into the host's tissue). The sensor 138 can include an elongated analyte sensor and can include an elongated conductive body, such as an elongated conductive core (e.g., a metal wire) or an elongated conductive core coated with one, two, three, four, five, or more layers of material, each of which may or may not be conductive. The elongated analyte sensor can be long and thin, yet flexible and strong. For example, in some embodiments, the smallest dimension of the elongated conductive body is less than 0.1 inches, less than 0.075 inches, less than 0.05 inches, less than 0.025 inches, less than 0.01 inches, less than 0.004 inches, less than 0.002 inches, less than 0.001 inches, and / or less than 0.0005 inches.

[0032] The sensor 138 may have a circular cross-section. In some embodiments, the cross-section of the elongated conductive body can be oval, rectangular, triangular, polyhedral, star-shaped, C-shaped, T-shaped, X-shaped, Y-shaped, irregular, etc. In some embodiments, a conductive wire electrode is used as the core. In other embodiments, the sensor 138 may be disposed on a substantially flat substrate. One or two additional conductive layers may be added to such an electrode (e.g., with an intervening insulating layer providing electrical isolation). The conductive layer may be made of any suitable material. In certain embodiments, it may be desirable to use a conductive layer that includes conductive particles (i.e., particles of a conductive material) in a polymer or other binder.

[0033] In some embodiments, the materials used to form the elongated conductive bodies (e.g., stainless steel, titanium, tantalum, platinum, platinum-iridium, iridium, certain polymers, and / or the like) can be strong and stiff, and therefore resistant to breakage. For example, in some embodiments, the ultimate tensile strength of the elongated conductive bodies is greater than 80 kPsi and less than 140 kPsi, and / or the Young's modulus of the elongated conductive bodies is greater than 160 GPa and less than 220 GPa. The yield strength of the elongated conductive bodies can be greater than 58 kPsi and less than 2200 kPsi.

[0034] Electronics module 140 may be releasably or permanently coupled to sensor 138. Electronics module 140 may include electronic circuitry related to measuring and processing continuous analyte sensor data. Electronics module 140 may be configured to execute algorithms related to processing and calibrating sensor data. For example, electronics module 140 may provide various aspects of the functionality of a sensor electronics module, such as those described in U.S. Patent Nos. 5,629,999 and 5,729,999, the entire contents of which are incorporated herein by reference. Electronics module 140 may include hardware, firmware, and / or software that enables measurement of analyte levels via a glucose sensor, such as sensor 138.

[0035] For example, electronics module 140 may include a potentiostat, a power supply for providing power to sensor 138, signal processing components, data storage components, and a communications module (e.g., a telemetry module) for one-way or two-way data communication between electronics module 140 and one or more receivers, repeaters, and / or display devices, such as devices 110-114. The electronics components may be affixed to a printed circuit board (PCB) or the like and may take a variety of forms. The electronics components may take the form of integrated circuits (ICs), such as application-specific integrated circuits (ASICs), microcontrollers, and / or processors. Electronics module 140 may also include sensor electronics configured to process sensor information, such as by storing data, analyzing data streams, calibrating analyte sensor data, estimating analyte values, comparing estimated analyte values ​​with corresponding measured analyte values ​​over time, and analyzing fluctuations in estimated analyte values. Examples of systems and methods for processing sensor analyte data are described in more detail in U.S. Patent Nos. 6,275,999, 6,282,123, 6,295,132, 6,317,143, 6,413,162, 6,512,177, 6,527,181, 6,617,192, 6,727,196, 6,737,166, 6,817,177, 6,825,196, 6,917,182, 6,925,197, 6,937,198, 6,947,199, 6,957,199, 6,967,199, 6,977,199, 6,987,199, 6,997,100, 6,997,102, 6,997,103, 6,997,110, 6,997,120, 6,997,130, 6,997,141, 6,997,150, 6,997,161, 6,997,172, 6,997,182, 6,997,19 ...

[0036] Additional sensor information can be found in U.S. Patent Nos. 5,823,997 and 5,823,997, the entire contents of which are incorporated herein by reference.

[0037] Any sensor shown or described herein may be an analyte sensor, a glucose sensor, and / or any other suitable sensor. The sensor described in the context of any example can be any sensor described herein or incorporated by reference. The sensors shown or described herein may be configured to sense, measure, detect, and / or interact with any analyte.

[0038] The term "analyte," as used herein, is a broad term and is to be given its ordinary and customary meaning to one of ordinary skill in the art (and is not limited to any special or customized meaning), and refers to, but is not limited to, a substance or chemical constituent in a biological fluid (e.g., blood, interstitial fluid, cerebrospinal fluid, lymphatic fluid, urine, sweat, saliva, etc.) that can be analyzed. Analytes can include naturally occurring substances, man-made substances, metabolites, or reaction products.

[0039] In some embodiments, the analyte for measurement by the sensing regions, devices, systems, and methods is glucose. However, other analytes may be detected, such as, but not limited to, ketone bodies; acetyl-CoA; acarboxyprothrombin; acylcarnitines; adenine phosphoribosyltransferase; adenosine deaminase; albumin; alpha-fetoprotein; amino acid profile (arginine (Krebs cycle), histidine / urocanic acid, homocysteine, phenylalanine / tyrosine, tryptophan); andrenostenedione; antipyrine; arabinitol enantiomers; arginase; benzoylecgonine (cocaine); biotinidase; biopterin; c-reactive protein; carnitine; carnosinase; CD4; ceruloplasmin; chenodeoxycholic acid; chloroquine; cholesterol; cholinesterase; cortisol; testosterone; choline; creatine kinase; creatine kinase MM isoenzyme; cyclosporin A; d-penicillamine; deethylase Chloroquine; Dehydroepiandrosterone sulfate; DNA (acetylation polymorphisms), alcohol dehydrogenase, alpha 1-antitrypsin, cystic fibrosis, Duchenne / Becker muscular dystrophy, glucose-6-phosphate dehydrogenase, hemoglobin A, hemoglobin S, hemoglobin C, hemoglobin D, hemoglobin E, hemoglobin F, D-Punjab, beta-thalassemia, hepatitis B virus, HCMV, HIV-1, HTL V-1, Leber's hereditary optic neuropathy, MCAD, RNA, PKU, Plasmodium vivax, sex differentiation, 21-deoxycortisol); desbutylhalofantrine; dihydropteridine reductase; diphtheria / tetanus antitoxin; erythrocyte arginase; erythrocyte protoporphyrin; esterase D; fatty acids / acylglycines; triglycerides; glycerol; free beta-human chorionic gonadotropin; free erythrocyte porphyrins; free thyroxine (FT4); free triiodothyronine (FT3); fumarylacetoacetase; galactose / gal-1-phosphate; galactose-1-phosphate uridyltransferase; gentamicin; glucose-6-phosphate dehydrogenase.Glutathione; glutathione peroxidase; glycocholate; glycosylated hemoglobin; halofantrine; hemoglobin variants; hexosaminidase A; human erythrocyte carbonic anhydrase I; 17-alpha-hydroxyprogesterone; hypoxanthine phosphoribosyltransferase; immunoreactive trypsin; lactate; lead; lipoproteins ((a), B / A-1, β); lysozyme; mefloquine; netilmicin; phenobarbitone; phenytoin; phytanic acid / pristanic acid; progesterone; prolactin; prolidase; purine nucleoside phosphorylase; quinine; reverse triiodothyronine tri-iodothyronine, rT3); selenium; serum pancreatic lipase; sisomicin; somatomedin C; specific antibodies (adenovirus, antinuclear antibody, anti-zeta antibody, arbovirus, pseudorabies virus, dengue virus, guinea worm, Echinococcus granulosus, Entamoeba histolytica, enterovirus, giardiasis, Helicobacter pylori, hepatitis B virus, herpes virus, HIV-1, IgE (atopic disease), influenza virus, Leishmania donovani, Leptospirosis, measles / mumps / rubella, Mycobacterium leprae, Mycoplasma pneumoniae, myoglobin, Onchocerciasis volvulus, parainfluenza virus, mammary gland Plasmodium parasites, poliovirus, Pseudomonas aeruginosa, respiratory syncytial virus, rickettsia (tsutsugamushi disease), Schistosoma mansoni, Toxoplasma gondii, Treponema pallidum, Trypanosoma cruzi / rangeli, vesicular stomatitis virus, Wuchereria bancrofti, yellow fever virus); specific antigens (hepatitis B virus, HIV-1); acetone (e.g., succinylacetone); acetoacetic acid; sulfadoxine; theophylline; thyrotropin (TSH); thyroxine (T4); thyroxine-binding globulin; trace elements; transferrin; UDP-galactose-4-epimerase; urea; uroporphyrinogen I synthase; vitamin A; leukocytes;and zinc protoporphyrin. Salts, sugars, proteins, fats, vitamins, and hormones naturally occurring in blood or interstitial fluid can also constitute analytes in certain embodiments. Analytes can be naturally occurring in biological fluids or can be endogenous, such as metabolites, hormones, antigens, antibodies, and the like. Alternatively, analytes can be introduced into the body or can be exogenous, such as contrast agents for imaging, radioisotopes, chemical agents, fluorocarbon-based synthetic blood, or drugs or pharmaceutical compositions, including, but not limited to, insulin; glucagon; ethanol; cannabis (marijuana, tetrahydrocannabinol, hashish); inhalants (nitrous oxide, amyl nitrite, butyl nitrite, chlorohydrocarbons, hydrocarbons); cocaine (crack cocaine); stimulants (amphetamine, methamphetamine, Ritalin, Silurt, Preludine, Didrex, Prestate, Boranil, Sandrek) antidepressants (barbiturates, tranquilizers such as methaqualone, Valium, Librium, Miltaunt, Serax, Equuanil, and Tranxine); hallucinogens (phencyclidine, lysergic acid, mescaline, peyote, and psilocybin); narcotics (heroin, codeine, morphine, opium, meperidine, Percocet, Percodan, Tasionex, fentanyl, Darvon, Talwin, and Lomotil); synthetic narcotics (fentanyl, meperidine, amphetamine, methamphetamine, and phencyclidine analogs, e.g., ecstasy); anabolic steroids;Analytes of interest include, but are not limited to, ascorbic acid, uric acid, dopamine, noradrenaline, 3-methoxytyramine (3MT), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxytryptamine (5HT), 5-hydroxyindoleacetic acid (FHIAA), and citric acid cycle intermediates, as well as other chemicals produced in the body, can also be analyzed.

[0040] Any of the features described at least in connection with Figure 1 may be applicable to all aspects and embodiments identified herein. Furthermore, any of the features of an embodiment may be independently combinable in any manner, partially or wholly, with other embodiments described herein; for example, one, two, or more embodiments may be combinable in whole or in part. Furthermore, any of the features of an embodiment may be optional in other aspects or embodiments. Any aspect or embodiment of a method may be performed by a system or device of another aspect or embodiment, and any aspect or embodiment of a system may be configured to perform a method of another aspect or embodiment.

[0041] 2A shows a perspective view of an exemplary on-skin wearable medical device in the form of an on-skin sensor assembly 200 configured to be deployed on the skin. The on-skin sensor assembly 200 may include a housing or base 202. The housing or base 202 may be configured to be worn on the skin of a host and may include a distal surface for facing toward the skin and a proximal surface 203 facing opposite the distal surface. The housing or base 202 may include an opening 205 for allowing an insertion element to pass therethrough and proximally retract from the skin. A patch 204, such as an adhesive patch, can connect the base 202 to the host's skin 206. The patch 204 may be disposed on the distal surface of the housing or base 202. In some examples, the adhesive patch 204 may include an engagement surface that engages the skin and includes an adhesive suitable for skin adhesion, such as a pressure-sensitive adhesive (e.g., acrylic, rubber-based, or other suitable type) bonded to a carrier substrate (e.g., spunlace polyester, polyurethane film, or other suitable type) for skin attachment (however, any suitable type of adhesive is contemplated). The on-skin sensor assembly 200 may include an electronics unit 208 (e.g., a transmitter) that may further include an analyte sensor, such as a transcutaneous analyte sensor (e.g., glucose sensor) 212 and a glucose sensor module 210 coupled to the base 202.

[0042] The applicator system can engage the adhesive patch 204 to the skin 206. The glucose sensor module 210 may be secured to the base 202 (e.g., via retaining elements such as snap-fit ​​and / or interference features, adhesive, welding, etc.) to ensure that the analyte sensor 212 (e.g., a glucose sensor) is coupled to the base 202. In an alternative embodiment, the sensor module 210 and the base 202 are pre-assembled or manufactured as a single component.

[0043] After the on-skin sensor assembly 200 is placed on the user's skin, the user (or applicator) can couple the electronics unit 208 (e.g., a transmitter) to the on-skin sensor assembly 200 via retention elements, such as snap-fit ​​features and / or interferometric features. The electronics unit 208 can measure and / or analyze glucose indicators sensed by the transcutaneous analyte sensor (e.g., glucose sensor) 212. The electronics unit 208 can transmit information (e.g., measurements, analyte data, glucose data) to remotely located devices (e.g., 110-114 shown in FIG. 1 ).

[0044] The on-skin sensor assembly 200 may be attached to the host using an applicator adapted to provide convenient and safe application. Such an applicator may also be used to attach the electronics unit 208 to the base 202, to insert the sensor 212 through the host's skin, and / or to connect the sensor 212 to the electronics unit 208. Once the electronics unit 208 is engaged with the base and the sensor 212 is inserted into the skin (and connected to the electronics unit 208), the sensor assembly can be detached from the applicator.

[0045] 2B shows a perspective view of electronics unit 208 coupled to base 202 via retention elements, such as snap-fit ​​features and / or interference features. In some embodiments, electronics unit 208 and base 202 are coupled by adhesive, welding, or other bonding techniques. Patch 204 on the distal surface of base 202 is configured to couple sensor assembly 200 to the skin.

[0046] 2C shows a perspective view of the on-skin sensor assembly 200. The on-skin sensor assembly 200 may be disposable or reusable. FIG. 2C further shows an electronics unit 208 coupled to the base 202 and an adhesive patch 204 configured to attach to the on-skin sensor assembly 200, which, when combined, may be held within an applicator.

[0047] 3 shows an example of an on-skin medical device in the form of an on-skin sensor assembly 300 with an electronics unit 302 configured for insertion into a cavity 304 of a base or housing 306. The base or housing 306 may be configured to be worn on the skin of a host and may include a distal surface for facing toward the skin and a proximal surface 305 facing opposite the distal surface. The electronics unit 302 may include one or more tabs 308 that couple to a portion of the housing 306 and allow the electronics unit 302 to be retained by the housing 306. The housing 306 may include an opening 310 for retracting an insertion element therethrough and proximally from the skin. The opening 310 may allow an insertion element (such as a needle) to pass through to deploy the transcutaneous analyte sensor 312 into the skin. The patch 314 may further include an opening 316 that can allow the sensor 312 and insertion element to pass through. The electronics unit 302 may be coupled to the housing 306 before or after deployment of the sensor 312 on the host's skin.

[0048] 4 shows an example of an on-skin medical device in the form of an on-skin sensor assembly 400, in which an electronics unit is integrated with a housing 402. The housing 402 may be configured to be worn on the skin of a host and may include a distal surface for facing towards the skin and a proximal surface 403 facing opposite the distal surface. The on-skin sensor assembly 400 is shown on the skin 404, with a patch 406 engaged to the skin 404.

[0049] Each of the embodiments in Figures 2A-4 can include an engagement surface for engaging the skin. The engagement surface, in embodiments, can be positioned on the patch, for example, on the distal surface of the patch, or in embodiments, can have another location. The engagement surface, in embodiments, can include an adhesive surface configured to adhere to the skin. The adhesive can be configured to adhere to the skin. Additional adhesive information is described in U.S. Patent Application Publication No. 2015 / 0129994, filed August 25, 2015, the entire contents of which are incorporated herein by reference. In embodiments, the engagement surface can be covered with a liner prior to deployment on the host's skin.

[0050] 5 illustrates a system for deploying an on-skin medical device on the skin. The system may, in some embodiments, include an applicator system. The system may include an applicator for an on-skin sensor assembly of an analyte sensor system, according to some embodiments. In some embodiments, other forms of the system may be utilized.

[0051] The applicator 500 may include an applicator housing 501, which may include an outer housing 504 and an inner housing 506, as well as other forms of housing in embodiments. The applicator housing 501, in embodiments, may be configured to hold a skin-mountable medical device. The applicator 500 may include a deployment mechanism, which may be configured to deploy the skin-mountable medical device onto the skin. The deployment mechanism, for example, in embodiments, may include an engagement portion for holding the skin-mountable medical device and releasing the skin-mountable medical device from the applicator housing 501 onto the skin. The engagement portion may include one or more retention elements. The deployment mechanism may include an insertion assembly for inserting at least a portion of the skin-mountable medical device into the skin. The insertion assembly may drive a portion of the skin-mountable medical device, such as an insertion element and a sensor, into the host's skin. The deployment mechanism may include a retraction assembly for retracting a portion of the skin-mountable medical device, such as the insertion element, from the skin.

[0052] In embodiments, the applicator 500 may include an actuation element 502 disposed on a side of the applicator 500, for example, on a side of the outer housing 504 of the applicator 500. In some embodiments, the actuation element 502 may be a button, a switch, a toggle, a slide, a trigger, a knob, a rotating member, a portion of the applicator 500 that deforms and / or bends, or any other suitable mechanism for actuating the insertion and / or retraction assembly of the applicator 500. In some embodiments, the actuation element 502 may be disposed anywhere, for example, on the top, upper side, lower side, or any other location of the applicator 500. The applicator 500 may be large enough for a host to grasp in their hand and press or otherwise actuate the actuation element 502 with, for example, their thumb, or index and / or middle finger.

[0053] The applicator 500 may be configured with one or more safety features such that the applicator 500 is prevented from activating until the safety feature is deactivated. In one example, the one or more safety features prevent the applicator 500 from being actuated unless the applicator 500 is pressed against the host's skin with sufficient force. Furthermore, as described in more detail in connection with one or more of FIGS. 6-20B below, the applicator 500 may be further configured such that one or more components within the applicator 500 retract based, at least in part, on the one or more components pressing against the host's skin with a force above a predetermined threshold, rather than based on the one or more components translating beyond a predetermined static distal position. In other words, the applicator 500 is capable of implementing force-based retraction triggering, rather than being limited to displacement-based retraction triggering.

[0054] 6 shows an exploded perspective view of the applicator 500 of FIG. 5 , according to some embodiments. The applicator 500 can include an outer applicator housing 504 with an actuating element 502. The outer applicator housing 504 can, in embodiments, be configured to be grasped by a user. The outer applicator housing 504 can be configured to translate distally upon force applied by the host to the applicator 500, particularly the inner housing 506, thereby aligning the actuating element 502 in a position that allows the applicator 500 to fire. Further description of the alignment process is provided below.

[0055] The applicator 500 further comprises an inner housing 506 configured to house at least one or more mechanisms utilized to apply the on-skin sensor assembly 508 to the skin of a host. A distal surface 510 of the bottom opening of the inner housing 506 can define a bottom surface of the applicator 500. In some examples, when the applicator 500 is pressed against the skin of a host, the skin can deform substantially convexly at the distal surface 510 such that at least a portion of the surface of the skin disposed at the bottom opening of the applicator inner housing 506 extends proximally beyond the plane defined by the distal surface 510 and into the bottom opening of the inner housing 506.

[0056] 7, the housing 501, particularly the inner housing 506, can include an internal cavity 503 for holding a skin-mountable medical device. The internal cavity 503 can have a distal end portion 505 at an opening for deploying the skin-mountable medical device therethrough. A proximal end portion 507 of the internal cavity 503 can contain a skin-mountable medical device coupled to a needle carrier assembly 516.

[0057] 6 , in some embodiments, first barrier layer 512 may be disposed over one or more openings in inner housing 506, such as opening 514, through which at least a portion of actuation element 502 may be configured to extend during actuation of applicator 500. In such embodiments, the portion of actuation element 502 may be configured to puncture or deform first barrier layer 512 upon actuation of applicator 500. First barrier layer 512 may include a gas-permeable material, such as Tyvek, or a gas-impermeable material, such as a metal foil, a polymer film, an elastomer, or any other suitable material.

[0058] The applicator 500 may further comprise a needle carrier assembly 516 including a needle hub 518 configured to couple an insertion element 520 to the needle carrier assembly 516. In some other embodiments, the insertion element 520 may be directly coupled to the needle carrier assembly 516. The insertion element 520 is configured to insert a sensor of the on-skin sensor assembly 508 into the skin of a host. In some embodiments, the insertion element comprises a needle, such as an open-sided needle, a needle with a deflectable tip, a curved needle, a polymer-coated needle, a hypodermic needle, or any other suitable type of needle or structure. In still other embodiments, the insertion element 520 may be integrally formed with the sensor and may be rigid enough to be inserted partially into the skin of a host with minimal or no structural support.

[0059] The applicator 500 may further include a holder 522 releasably coupled to the needle carrier assembly 516, the holder 522 configured to guide the needle carrier assembly 516 and the on-skin sensor assembly 508 while coupled to the needle carrier assembly 516, for example, during translation from at least a proximal position to a distal insertion position. As described in more detail below, the on-skin sensor assembly 508 may be detached or released from the holder 522 and / or the needle carrier assembly 516 once the on-skin sensor assembly 508 is disposed on the skin of the host. For example, the engagement portion or one or more retaining elements may release the on-skin wearable medical device from the applicator housing 501.

[0060] The applicator 500 may further include an insertion assembly configured to translate the insertion element 520, the needle hub 518, the needle carrier assembly 516, and the on-skin sensor assembly 508 distally from a proximal position to a distal insertion position. Such an insertion assembly may include at least one spring for inserting at least a portion of the on-skin device into the skin. The insertion assembly may include a first spring 524. The first spring 524 may be a compression spring or any suitable type of spring and may have a first end in contact with or coupled to the inner applicator housing 506 and a second end in contact with or coupled to the holder 522. The first spring 524 is configured to translate the holder 522, the needle carrier assembly 516, the needle hub 518, the insertion element 520, and the on-skin sensor assembly 508 distally to the distal insertion position upon actuation of the insertion assembly. In a substantially distal insertion position, the needle carrier assembly 516 may be separated from the holder 522 and the on-skin sensor assembly 508 .

[0061] Applicator 500 may further include a retraction assembly for retracting insertion element (e.g., needle) from the skin. Retraction assembly may be configured to translate needle carrier assembly 516, needle hub 518, and insertion element 520 in a proximal direction from a distal insertion position to a proximal retracted position. In some embodiments, the initial proximal position may be the same as the proximal retracted position. In other embodiments, the initial proximal position may be different from the proximal retracted position. Such a retraction assembly may include at least one spring. Retraction assembly may include second spring 526. Second spring 526 may be a compression spring or any suitable type of spring and may have a first end that contacts or is coupled to holder 522, at least until retracted, and a second end that contacts or is coupled to at least one spring retaining element (e.g., 528a, 528b in FIGS. 10-14 ). The second spring 526 is configured to translate the needle carrier assembly 516, the needle hub 518, and the insertion element 520 proximally from a distal insertion position to a proximal retracted position in response to the on-skin sensor assembly 508 contacting the host's skin and / or the first end of the second spring 526 reaching a travel limit with a force above a predetermined threshold sufficient to overcome at least one spring retaining element (e.g., 528a, 528b in FIGS. 10-14 ). In some examples, a stop feature (not shown) may be located at the bottom of the applicator 500, for example, on a distal portion of the inner housing 506. Such a stop feature may be configured to contact one or more of the on-skin sensor assembly 508, the needle carrier assembly 516, or the holder 522 at the distal insertion position.

[0062] In some embodiments, second barrier layer 530 may be disposed over the bottom opening of inner housing 506. Second barrier layer 530 may comprise a gas-permeable material, such as Tyvek, or a gas-impermeable material, such as a metal foil or film. In some embodiments, second barrier layer 530 may be removed by the host prior to use of applicator 500. In embodiments comprising one or both of first barrier layer 512 and second barrier layer 530, such layers may provide a sterile environment between applicator 500 and the external environment and / or may allow for the ingress and egress of gases, such as during sterilization.

[0063] A brief description of some aspects of the operation of applicator 500 follows below with reference to Figures 7-9, which show several cross-sectional views of applicator 500 of Figures 5 and 6 in operation, according to some embodiments. Figures 7-9 may correspond, for example, to applicator 500 cut along section line A-A' shown in Figure 5.

[0064] 7 shows the state of applicator 500 before activation. Holder 522 includes an insertion assembly retaining element 532 that is configured to contact inner housing 506 to secure holder 522, needle carrier assembly 516, needle hub 518, insertion element 520, and on-skin sensor assembly 508 in the pre-activated state.

[0065] The needle carrier assembly 516 includes an engagement portion of the applicator. The engagement portion may include a plurality of wearable retention and / or alignment elements 534a, 534b that extend through the holder 522 and are configured to releasably couple the on-skin sensor assembly 508 to the holder 522 and / or the needle carrier assembly 516. The engagement portion may have other configurations in embodiments. The wearable retention elements 534a, 534b may include, for example, arms, deflection elements, tabs, detents, snaps, or any other feature capable of retention functionality. In some embodiments, the wearable retention elements 534a, 534b may extend around, rather than through, the holder 522. While two wearable retention elements are shown, any number of wearable retention elements is contemplated. In some embodiments, the wearable retaining elements 534a, 534b may include a snap fit, a friction fit, interference features, an elastomeric grip, and / or an adhesive configured to couple the on-skin sensor assembly 508 with the needle carrier assembly 516 and / or the holder 522.

[0066] Inner housing 506 may include a spring 536 configured to contact outer housing 504 and maintain a predetermined spacing between outer housing 504 and inner housing 506 in the pre-actuated orientation of FIG. 7. Spring 536 may be a compression spring, a leaf spring, a flex arm spring, a foam or rubber strip, or the like. In some other embodiments, outer housing 504 may include spring 536, and spring 536 may be configured to contact inner housing 506 in a manner opposite to that shown in FIG. 7.

[0067] Actuation of the applicator 500 may involve the host pressing the applicator 500 against their skin with sufficient force to translate the outer housing 504 distally toward and relative to the inner housing 506, as indicated by arrow 538, until the actuation element 502 is aligned with the opening 514 of the inner housing 506 and the insertion assembly retaining element 532 of the holder 522. The insertion assembly retaining element 532 may comprise, for example, an arm, a deflection element, a tab, a detent, a snap, or any other feature capable of retaining functionality. Once such alignment is achieved, the host may initiate (e.g., push) the actuation element 502, as indicated by arrow 540, thereby deflecting the insertion assembly retaining element 532 sufficiently to release the holder 522 from the inner housing 506. In some other embodiments, the applicator 500 may be configured such that the actuating element 502 may be actuated first, but the actual insertion is not triggered until the outer housing 504 has been sufficiently translated distally toward and relative to the inner housing 506. In still other embodiments, the actuating element 502 may be biased toward the center of the applicator 500 such that the actuating element 502 does not need to be explicitly actuated by the host, but instead, the actuating element 502 may be configured to automatically begin insertion once the outer housing 504 has been sufficiently translated distally toward and relative to the inner housing 506.

[0068] Such a configuration offers several advantages. First, the translation of outer housing 504 relative to inner housing 506 prior to actuation provides a measure of drop protection so that applicator 500 cannot fire prematurely if accidentally dropped. Second, spring 536 provides a biasing force that the host must actively overcome by pressing applicator 500 into their skin prior to firing, thereby reducing the likelihood of actuating applicator 500 before it is properly positioned. Furthermore, the host may decide not to fire applicator 500 and cease pressing applicator 500 against their skin, in which case spring 536 will bias against outer housing 504, allowing outer housing 504 to return to its initial state.

[0069] The holder 522, needle carrier assembly 516, needle hub 518, insertion element 520, on-skin sensor assembly 508, first spring 524, and second spring 526 are all shown in a pre-actuated position in FIG.

[0070] Figure 8 shows the applicator 500 during insertion of the on-skin sensor assembly 508, but before retraction of the needle carrier assembly 516. The first spring 524 drives the holder 522, needle carrier assembly 516, needle hub 518, insertion element 520, and on-skin sensor assembly 508 distally toward the distal insertion position. Figure 8 shows a position where the on-skin sensor assembly 508 is in contact with the host's skin, but the holder 522 has not yet been fully driven by the first spring 524 into contact with the on-skin sensor assembly 508 or the host's skin.

[0071] In some embodiments, the mass of each of the holder 522, needle carrier assembly 516, needle hub 518, insertion element 520, and on-skin sensor assembly 508 may be specifically designed to reduce or substantially eliminate the tendency of the needle carrier assembly 516, needle hub 518, insertion element 520, and on-skin sensor assembly 508 to detach from the holder 522 due to inertial forces while being driven distally during insertion. In some embodiments, the force exerted by the first spring 524 may be selected to be sufficient for proper operation of the applicator 500, but not so great as to further exacerbate such inertially triggered detachment described above. In some embodiments, a spring (not shown) may be configured to exert a force on a portion of the needle carrier assembly 516, e.g., in a distal direction, sufficient to prevent inertially triggered detachment of the needle carrier assembly 516 from the holder 522 during insertion.

[0072] FIG. 9 shows the applicator 500 in operation as the needle carrier assembly 516, needle hub 518, and insertion element 520 are retracted proximally by the second spring 526. In FIG. 9, the first spring 524 fully drives the on-skin sensor assembly 508 against the host's skin. In this position, the second spring 526 is released from the spring retaining element (e.g., 528a, 528b in FIGS. 10-14 ) and drives the needle carrier assembly 516, needle hub 518, and insertion element 520 proximally from the distal insertion position. When the needle carrier assembly 516 reaches the proximal retracted position, the needle carrier retaining element 542 of the holder 522 engages the needle carrier assembly 516, thereby maintaining the needle carrier assembly 516, needle hub 518, and insertion element 520 in a locked retracted position that restricts access to the insertion element 520. The needle carrier retaining element 542 may comprise, for example, an arm, a deflection element, a tab, a detent, a snap, or any other feature capable of retaining function. In this retracted position, the needle carrier assembly 516, needle hub 518, and insertion element 520 are prevented from moving distally.

[0073] A further description of some aspects of the operation of applicator 500 follows below with reference to Figures 10-12, which show several cross-sectional views of applicator 500 of Figures 5 and 6 in operation, according to some embodiments. Figures 10-12 may correspond, for example, to applicator 500 cut along section line B-B' shown in Figure 5. For ease of illustration, needle hub 518 and insertion element 520 are not shown in Figures 10-12.

[0074] FIG. 10 illustrates the state of the applicator 500 prior to actuation. For ease of illustration, the on-skin sensor assembly 508 is not shown in FIG. 10 . The holder 522 includes spring retaining elements 528a, 528b configured to contact the first end of the second spring 526 and retain it in a pre-actuated state, e.g., during insertion, while the second end of the spring 526 is in contact with the needle carrier assembly 516. The spring retaining elements 528a, 528b may include, for example, arms, deflection elements, tabs, detents, snaps, or any other feature capable of retaining functionality. While two spring retaining elements 528a, 528b are shown, at least one spring retaining element is contemplated. In some embodiments, the applicator 500 may include one spring retaining element, as shown in FIGS. 21-24 . In some embodiments, the applicator 500 may include three spring retaining elements. In some embodiments, applicator 500 can include four spring retaining elements. In some embodiments, spring retaining elements 528a, 528b are deflectable arms, rigid arms, deformable features, snaps, catches, or hooks. In some embodiments, spring retaining elements 528a, 528b can be actively deflected by one or more features within applicator 500.

[0075] Needle carrier assembly 516 includes backstop features 544a, 544b configured to prevent lateral deflection of spring retaining elements 528a, 528b in a proximal starting position, for example, at least during insertion, thereby supporting retention of second spring 526 between spring retaining elements 528a, 528b and holder 522 until retraction. While two backstop features are illustrated, any number of backstop features is contemplated. The number of backstop features may equal the number of spring retaining elements.

[0076] FIG. 13 shows a close-up view of spring retaining element 528b and backstop feature 544b. In FIG. 13, first spring 524 drives holder 522, needle carrier assembly 516, and on-skin sensor assembly 508 distally toward the distal insertion position. Backstop feature 544b is shown engaged with spring retaining element 528b, preventing spring retaining element 528b from deflecting laterally, thereby preventing second spring 526 from releasing. As shown in FIG. 13, the proximal end of spring retaining element 528b can be offset from the distal end of backstop feature 544b by a distance α. In some embodiments, distance α is the length required for spring retaining element 528b to traverse along backstop feature 544b so that spring retaining element 528b passes through backstop feature 544b. Backstop feature 544b may feature a beveled surface to guide spring retaining element 528b. The distal end of needle carrier assembly 516 and the distal end of holder 522 may be offset from one another by at least the same distance α to allow spring retaining element 528b to traverse distally over backstop feature 544b.

[0077] It can be appreciated that the frictional force between the corresponding contact surfaces of backstop feature 544b and spring retaining element 528b can at least partially determine the amount of force required to release spring retaining element 528b from backstop feature 544b. This force can allow lateral deflection of spring retaining element 528b and, therefore, expansion of second spring 526. In some embodiments, the amount of force is at least 0.1 pounds. In some embodiments, the amount of force is at least 0.5 pounds. In some embodiments, the amount of force is at least 1 pound. In some embodiments, the amount of force is at least 2 pounds. In some embodiments, the amount of force is at least 3 pounds. In some embodiments, the amount of force is at least 4 pounds. In some embodiments, the amount of force is at least 5 pounds.

[0078] Although the figure shows backstop feature 544b preventing lateral deflection of spring retaining element 528b in a radially outward direction, it is contemplated that the opposite structural relationship may be achieved. For example, the angled surface of spring retaining element 528b may be inverted to face the opposite direction as shown in FIG. 13 . Additionally, the angled surface of spring retaining element 528b may be biased radially inward against backstop feature 544b by second spring 526. In such an embodiment, backstop feature 544b may be located radially inward of spring retaining element 528b.

[0079] Thus, in some embodiments, the materials utilized to form holder 522 and needle carrier assembly 516 may be selected based on the amount of force desired to release spring retaining element 528b for lateral deflection. Examples of such materials may include polycarbonate, ABS, PC / ABS, polypropylene, HIPS (High impact polystyrene), polybutylene terephthalate (PBT), polyoxymethylene (POM), acetal, polyacetal, polyformaldehyde, PTFE, high density polyethylene (HDPE), ultra-high-molecular-weight polyethylene (UHMWPE), nylon, polyethylene terephthalate (PET), thermoplastic elastomer (TPE), thermoplastic polyurethane (TPU), TPSiv, cycloolefin polymer (COP), cycloolefin copolymer (COC), and / or liquid-crystal polymer (LCP).

[0080] The angle θ of the portion of the spring retaining element 528b that contacts the second spring 526 can also affect the amount of frictional force required to laterally deflect the spring retaining element 528b and thus release the second spring 526. Accordingly, the angle θ may be selected based on the desired amount of force required to laterally deflect the spring retaining element 528b sufficiently to release the second spring 526. In some embodiments, the angle θ is at least 1 degree relative to a vertical axis of the spring retaining element 528b. In some embodiments, the angle θ is at least 5 degrees. In some embodiments, the angle θ is at least 10 degrees. In some embodiments, the angle θ is at least 15 degrees. In some embodiments, the angle θ is at least 20 degrees. In some embodiments, the angle θ is between about 30 degrees and 45 degrees. Additionally, the force profile of the second spring 526 can affect the target amount of frictional force required to laterally deflect the spring retaining element 528b. Thus, in some embodiments, the force profile of second spring 526 may be considered when selecting one or both of the materials for forming holder 522 and needle carrier assembly 516, as well as the angle θ of the portion of spring retaining element 528b that contacts second spring 526.

[0081] The angle β of the spring retaining element 528b relative to the vertical axis can also affect the amount of frictional force that causes the spring retaining element 528b to deflect laterally and thus release the second spring 526. By contacting the spring retaining element 528b, the second spring 526 can apply a force to the spring retaining element 528b at a distance d from the bottom of the spring retaining element 528b, which creates a torque moment sufficient to induce lateral deflection of the spring retaining element 528b.

[0082] 13 further illustrates needle carrier assembly 516 with a flexure element 546 configured to contact spring retaining element 528b and maintain spring retaining element 528b in a laterally flexed orientation after second spring 526 initially flexes spring retaining element 528b and sufficiently drives needle carrier assembly 516 in a proximal direction, as shown in more detail in FIG. 14. Flexure element 546 may prevent spring retaining element 528b from contacting the windings of second spring 526 during extension of second spring 526, smoothing operation of applicator 500 and preventing energy designed to be released by second spring 526 to drive needle carrier assembly 516 in a proximal direction from being absorbed by undesired contact with spring retaining element 528b during release of second spring 526.

[0083] In some embodiments, the angle θ of the portion of the spring retaining element 528b that contacts the second spring 526 can be substantially 90° (e.g., flat), and the flexure element 546 can have a sloped or angled surface that contacts the spring retaining element 528b in the position shown in FIG. 13. In such embodiments, in addition to the functionality described above, the flexure element 546 can be configured to initially deflect the spring retaining element 528b when the first spring 524 drives the holder 522 from the position shown in FIG. 13 to the position shown in FIG. 14.

[0084] In some embodiments, inner housing 506 can include a protrusion 548 extending distally from inner housing 506. Protrusion 548 can be configured to contact at least one of spring retaining elements 528a, 528b and backstop features 544a, 544b in a pre-actuated state such that spring retaining elements 528a, 528b are prevented from deflecting laterally until holder 522 and needle carrier assembly 516 have translated distally at least a predetermined minimum distance. Thus, protrusion 548 can provide a measure of drop protection to prevent applicator 500 from prematurely firing in response to a concussive shock due to being dropped prior to intended actuation.

[0085] Returning to FIG. 10 , the inner housing 506 may further include an engagement element 550 configured to engage a protrusion 552 of the needle carrier assembly 516 when the needle carrier assembly 516 translates distally beyond a predetermined threshold, thereby preventing the needle carrier assembly 516 from translating distally beyond the predetermined threshold. This is contemplated to ensure retraction of the needle carrier assembly in the event of an air or dry firing that is somehow activated when the applicator 500 is not held against the host's skin. In some embodiments, the predetermined threshold may correspond to the distal end of the needle carrier assembly 516 extending beyond a point proximal to the distal end of the inner housing 506 to a point substantially coincident with the distal end of the inner housing 506 or to a point distal to the distal end of the inner housing 506. In some embodiments, the engagement element 550 comprises a hook, a U-shaped structure, a loop, a protrusion, or any other structure capable of engaging with the protrusion 552 as described above.

[0086] 11 shows the applicator 500 after actuation, at the beginning of the force retract feature process at or near the distal insertion position where the on-skin sensor assembly 508 may contact the host's skin. The first spring 524 drives the holder 522, needle carrier assembly 516, needle hub 518, insertion element, and on-skin sensor assembly 508 distally toward the distal insertion position. During proper operation, the holder 522 and on-skin sensor assembly 508 should be pressed against the host's skin. However, FIG. 11 may also show a dry-fire condition in which the applicator 500 is not properly pressed against the host's skin before triggering the applicator 500. Thus, when first spring 524 drives holder 522 and needle carrier assembly 516 distally beyond a predetermined threshold, engagement element 550 contacts protrusion 552, thereby preventing needle carrier assembly 516 from further moving distally, while holder 522 is driven distally far enough so that backstop features 544 a, 544 b of needle carrier assembly 516 no longer contact spring retaining elements 528 a, 528 b in the distal insertion position, thereby releasing the first end of second spring 526 and initiating retraction, even when applicator 500 is dry fired. The insertion force provided by first spring 524 may be sufficient to further overcome the frictional force between the corresponding contact surfaces of backstop feature 544 b and spring retaining element 528 b.

[0087] 14 , the first spring 524 drives the holder 522, needle carrier assembly 516, and on-skin sensor assembly 508 in a distal direction against the host's skin. As the first spring 524 drives the holder 522, needle carrier assembly 516, and on-skin sensor assembly 508 against the host's skin, the skin provides a counterforce to the force generated by the first spring 524. The skin may counter the force of the first spring 524 and bias against the distal end of the on-skin sensor assembly 508. Because the distal end of the holder 522 is offset from the distal end of the on-skin sensor assembly 508, as shown in FIG. 13 , the counterforce provided by the skin is transmitted to the holder 522 as the first spring 524 continues to drive the holder 522 toward the skin while the on-skin sensor assembly 508 is pressed against the skin. The reaction force provided by the skin allows spring retaining element 528b to be displaced past backstop feature 544b. Once spring retaining element 528b clears distance α past backstop feature 544b, second spring 526 can deflect spring retaining element 528b laterally, thereby releasing second spring 526 and driving needle carrier assembly 516 proximally. Alternatively, as described above in connection with FIG. 13 , if angle θ of the portion of spring retaining element 528b in contact with second spring 526 is substantially 90° (e.g., flat), the sloped or angled surface of flexing element 546 in contact with spring retaining element 528b will deflect spring retaining element 528b sufficiently to release second spring 526, thereby driving needle carrier assembly 516 proximally.

[0088] In some embodiments, the engaging element 550 can engage the protrusion 552 even when the applicator 500 is pressed against the user's skin. In such embodiments, the engaging element 550 engages the protrusion 552 when the first spring 524 drives the holder 522, the needle carrier assembly 516, and the on-skin sensor assembly 508 against the host's skin. As explained above, the engaging element 550 prevents the needle carrier assembly 516 from moving distally when the engaging element 550 engages the protrusion 552. This allows the spring retaining elements 528a, 528b to move away from the backstop features 544a, 544b, allowing the second spring 526 to release. The engagement of the engaging element 550 with the protrusion 552 may add additional force to the counterforce provided by the skin, thus increasing the energy required to overcome the frictional engagement between the spring retention elements 528a, 528b and the backstop features 544a, 544b. In some cases, the engagement of the engaging element 550 with the protrusion 552 provides an immediate impact force that converts at least a portion of the initial energy of the first spring 524 into the energy necessary to overcome the frictional engagement between the spring retention elements 528a, 528b and the backstop features 544a, 544b. It is contemplated that such embodiments may benefit users with softer skin or a higher body fat percentage.

[0089] 12, which shows the applicator 500 in operation, the needle carrier assembly 516 is urged proximally retracted by the second spring 526, as indicated by arrow 554. In FIG. 12, when the on-skin sensor assembly 508 contacts the host's skin with the backstop features 544a, 544b no longer securing the spring retaining elements 528a, 528b, the first end of the second spring 526 presses against the spring retaining elements 528a, 528b with sufficient force to deflect the spring retaining elements 528a, 528b to a distal insertion position, allowing the second spring 526 to clear the spring retaining elements 528a, 528b and drive the needle carrier assembly 516 proximally, thereby maintaining the needle carrier assembly 516, needle hub 518 (see FIGS. 7-9), and insertion element 520 (see FIGS. 7-9) in a locked, retracted position, even in the event of a dry fire.

[0090] 15 and 16 show close-up views of some features of an applicator, such as applicator 500, according to some embodiments.

[0091] In Figure 15, a first spring 524 (see Figures 6-12) urges the holder 522 and the needle carrier assembly and on-skin sensor assembly 508 in a distal direction indicated by arrow 556, toward a distal insertion position. An engagement portion in the form of a retaining element 534b of the needle carrier assembly is releasably coupled to the on-skin sensor assembly 508. As illustrated, during insertion and near the distal insertion position, the holder 522 contacts the spring retaining element 534b, preventing the spring retaining element 534b from deflecting laterally, thereby securely securing the on-skin sensor assembly 508 to the needle carrier assembly.

[0092] In Figure 16, the second spring 526 (see Figures 6-12) is urging the needle carrier assembly 516 proximally from the distal insertion position. The holder 522 has been driven sufficiently distally that, at the distal insertion position, the holder 522 is no longer in contact with the wearable retaining element 534b. The wearable retaining element 534b is therefore free to flex laterally, thereby releasing the on-skin sensor assembly 508 from the wearable retaining element 534b and therefore from the needle carrier assembly 516. The needle carrier assembly 516 is now driven proximally by the second spring 526, while the on-skin sensor assembly 508 is secured to the host's skin. Furthermore, in some embodiments, as the holder 522 is driven to the distal insertion position and substantially held in that position by the first spring 524, the holder 522 can press against one or both of the on-skin sensor assembly 508 or the adhesive patch of the on-skin sensor assembly 508, and can support one or both during attachment to the host's skin.

[0093] Figure 17 shows a perspective partial cutaway view of the needle carrier assembly 516, needle hub 518, and on-skin sensor assembly 508 of the applicator 500 of Figures 5 and 6, according to some embodiments. Figure 18 shows a cross-sectional view of the needle hub 518 and on-skin sensor assembly 508, according to some embodiments. Figure 19 shows a top view of a portion of the needle carrier assembly 516 and needle hub 518, according to some embodiments. The following is a description of these features with reference to Figures 17-19.

[0094] On-skin sensor assembly 508 includes sensor assembly opening 560. Needle hub 518 couples insertion element 520 to needle carrier assembly 516 and is configured to substantially maintain a desired orientation of insertion element 520 during insertion of a sensor of on-skin sensor assembly 508 into the skin of a host.

[0095] The needle hub 518 comprises a plurality of upper arms 562a, 562b, a plurality of lower arms 564a, 564b, and a base 566. While two upper arms and two lower arms are illustrated, any number of arms is contemplated, such as a single upper and lower arm. In some embodiments, the upper arms 562a, 562b and the lower arms 564a, 564b can be flexible such that when the needle hub 518 is coupled to the needle carrier assembly 516, the upper arms 562a, 562b and the lower arms 564a, 564b secure the needle hub 518 in a desired orientation relative to the needle carrier assembly 516. For example, the upper arms 562a, 562b may be configured to flex radially inward when positioned through a carrier opening 568 in the needle carrier assembly 516, such that the upper arms 562a, 562b contact an upper surface of the needle carrier assembly 516 adjacent the carrier opening 568, and the lower arms 564a, 564b contact a lower surface of the needle carrier assembly 516 adjacent the carrier opening 568. Such an arrangement allows for a compliant fit between the needle carrier assembly 516 and the needle hub 518, with the lower arms 564a, 564b flexing to allow the upper arms 562a, 562b to expand after clearing the surface of the carrier opening 568. The lower arms 564a, 564b can partially or completely relax to bias the needle hub distally and reduce the clearance between the needle hub and the needle carrier that would otherwise exist in a non-compliant fit. Additionally, the upper arms 562 a , 562 b and lower arms 564 a , 564 b also help maintain contact between the base 566 and the top surface of the on-skin sensor assembly 508 .

[0096] The base 566 includes an anti-rotation feature. The anti-rotation feature may comprise a key having a shape complementary to at least a portion of the sensor assembly opening 560 of the on-skin sensor assembly 508 and may be configured to prevent rotation of the base 566 within the sensor assembly opening 560, for example, to substantially prevent rotation of the needle hub 518 relative to the on-skin sensor assembly 508 about an axis 567 parallel to the insertion element 520. Additionally, or alternatively, a top surface of the needle carrier assembly 516 adjacent the carrier opening 568 may include grooves 570 configured to receive the upper arms 562 a, 562 b when the upper arms 562 a, 562 b are disposed through the carrier opening 568 in an orientation complementary to the orientation of the grooves 570, thereby securing the needle hub 518 relative to the needle carrier assembly 516, as shown in FIG.

[0097] In some embodiments, the base 566 further comprises a substantially flat surface configured, in some cases, to mate with a top or proximal surface of the on-skin sensor assembly 508 when the anti-rotation feature of the base 566 is engaged within the opening 560 of the on-skin sensor assembly 508 and maintain the insertion element 520 in a substantially perpendicular orientation relative to the top surface of the on-skin sensor assembly 508.

[0098] Based at least on the above-described features of the needle hub 518, the on-skin sensor assembly 508, and / or the needle carrier assembly 516, the base 566 allows for easy assembly during manufacturing, including, but not limited to, proper alignment and pre-assembly of the insertion element 520 onto the on-skin sensor assembly 508, and / or the ability to easily engage the assembly of the needle hub 518, the insertion element 520, the sensor, and the on-skin sensor assembly 508 with other portions of the assembled applicator 500.

[0099] 20A and 20B show perspective views of locking features for insertion elements in the form of needles 600a, 600b for use in an applicator for an analyte sensor system, according to some embodiments. For example, needle 600a in FIG. 20A includes a locking feature comprising a ridge 602 configured to mate with a complementary feature in, for example, needle hub 518. Alternatively, needle 600b in FIG. 20B includes a locking feature comprising a groove 604 configured to mate with a complementary feature in, for example, needle hub 518.

[0100] In yet another alternative, any of the insert elements described in this disclosure may comprise a locking feature that, for example, heat stakes the selected insert element to the needle hub 518. In yet another alternative, any of the insert elements described in this disclosure may comprise a locking feature that, for example, comprises one or more friction-fit or snap-fit ​​elements that secure the selected insert element to the needle hub 518. In yet another alternative, any of the insert elements described in this disclosure may comprise a locking feature that, for example, comprises complementary clamshell elements on the selected insert element and the needle hub 518 that are configured to mate with one another. In yet another alternative, any of the insert elements described in this disclosure may comprise a locking element that, for example, comprises one or more insert-molded elements configured to couple the selected insert element to the needle hub 518.

[0101] During manufacturing, the applicator 500 may be assembled in stages. For example, without limitation, if present, the first barrier layer 512 may be attached to the inner housing 506. The insertion element 520 may be coupled to the needle hub 518, which may then be coupled to the on-skin sensor assembly 508. The second spring 526 may be installed in the holder 522 or the needle carrier assembly 516, which may then be placed in the holder 522 and attached to the needle hub 518 and on-skin sensor assembly 508 via wearable retention elements 534a, 534b. The first spring 524 may be placed in the holder 522, which may then be placed in the inner housing 506. The inner housing 506 may be inserted into and secured to the outer housing 504. If present, the second barrier layer 530 may be attached to the inner housing 506. If a separate element, actuation element 502 may be disposed within outer housing 504. Any labeling, sterilization, and / or packaging may then be applied to applicator 500.

[0102] 21-23 illustrate several cross-sectional views and various features and operating positions of yet another applicator 700 for an on-skin sensor assembly of an analyte sensor system, according to some embodiments.

[0103] Applicator 700 can include an outer applicator housing 504 that includes actuating element 502. Outer applicator housing 504 can be configured to translate distally under force applied by the host of applicator 700, thereby aligning actuating element 502 in a position that allows applicator 700 to fire, the alignment illustrated by FIG. 21. As discussed above in connection with applicator 500, in some embodiments, actuating element 502 can be located anywhere, such as on the top, upper side, lower side, or any other location of applicator 700.

[0104] The applicator 700 further comprises an inner housing 506 configured to house one or more mechanisms utilized to apply the on-skin sensor assembly 508 to the skin of a host. A distal surface 510 of the bottom opening of the inner housing 506 can define a bottom surface of the applicator 700. In some examples, when the applicator 700 is pressed against the skin of a host, the skin can deform substantially convexly at the distal surface 510 such that at least a portion of the surface of the skin disposed at the bottom opening of the inner housing 506 extends beyond the plane defined by the distal surface 510, in a proximal direction, and into the bottom opening of the inner housing 506.

[0105] Although not shown in FIGS. 21-23 , inner housing 506 may include a spring 536 configured to contact outer housing 504 and maintain a predetermined spacing between outer housing 504 and inner housing 506 in a pre-actuated orientation (see FIG. 7 ). Spring 536 may be a compression spring, a leaf spring, a flex arm spring, a foam or rubber strip, or the like. In some other embodiments, outer housing 504 may include spring 536, and spring 536 may be configured to contact inner housing 506.

[0106] The applicator 700 may further comprise a needle carrier assembly 702. The needle carrier assembly 702 comprises engagement portions, which may be in the form of wearable retention and / or alignment elements 534a, 534b, which are configured to pass through the holder 704 and releasably couple the on-skin sensor assembly 508 to the holder 704 and / or the needle carrier assembly 702. Although two wearable retention and / or alignment elements are illustrated, any number of wearable retention and / or alignment elements is contemplated.

[0107] The applicator 700 further comprises a needle hub 518 configured to couple an insertion element 520 to the needle carrier assembly 702. The insertion element 520 is configured to insert a sensor of the on-skin sensor assembly 508 into the skin of a host. In some embodiments, the insertion element 520 comprises a needle, such as an open-side needle, a needle with a flexible tip, a curved needle, a polymer-coated needle, a hypodermic needle, or any other suitable type of needle or structure. In still other embodiments, the insertion element 520 may be integrally formed with the sensor, and the insertion element 520 may be sufficiently rigid to be inserted partially into the skin of a host with minimal or no structural support.

[0108] The applicator 700 may further include a holder 704 releasably coupled to the needle carrier assembly 702, the holder 704 being configured to guide the on-skin sensor assembly 508 while coupled to the needle carrier assembly 702, for example, at least during translation from a proximal position to a distal insertion position. As described above in connection with the applicator 500, once the on-skin sensor assembly 508 is positioned on the skin of the host, the on-skin sensor assembly 508 may be removed or released from the holder 704 and / or the needle carrier assembly 702.

[0109] The applicator 700 may further include an insertion assembly configured to translate the insertion element 520, the needle hub 518, and the needle carrier assembly 702 distally from a proximal position to a distal insertion position. Such an insertion assembly may include a first spring 524. The first spring 524 may be a compression spring or any suitable type of spring and may have a first end that contacts or couples with the inner applicator housing 506 and a second end that contacts or couples with the holder 704. The first spring 524 is configured to translate the holder 704, the needle carrier assembly 702, the needle hub 518, the insertion element 520, and the on-skin sensor assembly 508 distally to the distal insertion position upon actuation of the insertion assembly. At substantially the distal insertion position, the needle carrier assembly 702 may be separated from the holder 704 and the on-skin sensor assembly 508.

[0110] The applicator 700 may further include a retraction assembly configured to translate the needle carrier assembly 702, the needle hub 518, and the insertion element 520 in a proximal direction from a distal insertion position to a proximal retracted position. In some embodiments, the initial proximal position may be the same as the proximal retracted position. In other embodiments, the initial proximal position may be different from the proximal retracted position. Such a retraction assembly may include a second spring 706. The second spring 706 may be a compression spring or any suitable type of spring and may have a first end that contacts or couples to the holder 704 and a second end that includes a tang 708 (e.g., a spring portion or spring end) disposed substantially along the diameter of the second spring 706 and that contacts or couples to a spring retaining element 710 of the holder 704 at least until retracted. The spring retaining element 710 may include, for example, an arm, a deflection element, a tab, a detent, a snap, or any other feature capable of retaining functionality. Spring retaining element 710 may have substantially the same form and function as spring retaining elements 528a, 528b of applicator 500, except as described below. Second spring 706 is configured to translate needle carrier assembly 702, needle hub 518, and insertion element 520 proximally from a distal insertion position to a proximal retracted position. Tang 708 of second spring 706 is released from spring retaining element 710 at the distal insertion position when spring retaining element 710 is not backed up by backstop element 712 and in response to the tang 708 of second spring 706 pressing against spring retaining element 710 with a force above a predetermined threshold sufficient to overcome and deflect spring retaining element 710.

[0111] Needle carrier assembly 702 further includes a backstop feature 712 configured to prevent lateral movement of spring retaining element 710 of holder 704, at least in a proximal pre-actuation position, thereby supporting retention of second spring 706 between spring retaining element 710 and holder 704 until retraction. In the orientation shown in FIG. 21 , second spring 706 exerts a force against spring retaining element 710, but backstop feature 712 prevents lateral deflection of retaining element 710.

[0112] Holder 704 further comprises needle carrier retaining element 542, which may comprise a deflectable arm, a rigid arm, a deformable feature, a snap, a catch, or a hook. Needle carrier retaining element 542 is configured to engage needle carrier assembly 702 when needle carrier assembly 702 reaches the proximal retracted position after actuation, thereby maintaining needle carrier assembly 702, needle hub 518, and insertion element 520 in a locked, retracted position and restricting access to insertion element 520.

[0113] Although not shown in Figures 21-23, inner housing 506 of applicator 700 may further include engagement element 550, and needle carrier assembly 702 may further include protrusion 552, and may function substantially as described above in connection with at least Figures 10-12.

[0114] 21-23, inner housing 506 of applicator 700 may further include a protrusion extending distally therefrom, substantially like protrusion 548 described above. Similar to that described above in connection with FIG. 13, this protrusion may be configured to contact at least one of spring retaining element 710 and backstop feature 712 in a pre-actuated state, such that spring retaining element 710 is prevented from deflecting laterally until holder 704 and needle carrier assembly 702 have translated distally at least a predetermined minimum distance. Thus, the protrusion may provide a measure of drop protection to prevent premature firing of applicator 700 in response to a concussive shock from being dropped prior to actuation.

[0115] Applicator 700 functions substantially similarly to applicator 500, except that instead of utilizing spring retaining elements 528a, 528b positioned along the outside of the second coil of spring 526 and configured to contact and retain the coil of second spring 526, applicator 700 utilizes spring retaining element 710 positioned along the inside of second spring 706 and configured to contact and retain a tang 708 of second spring 706 along the diameter of second spring 706. Locating spring retaining element 710 within and substantially along the center of second spring 706, rather than along the outside of second spring 706, further ensures that spring retaining element 710 does not contact the coil of second spring 706 as second spring 706 extends during retraction, thereby facilitating operation of applicator 700. Additionally, the arrangement including spring retaining element 710 as opposed to spring retaining elements 528a, 528b reduces the risk and difficulty of ensuring that multiple spring retaining elements are triggered or overcome substantially simultaneously.

[0116] 21 illustrates the state of the applicator 700 prior to actuation, according to some embodiments. The holder 704, needle carrier assembly 702, needle hub 518, insertion element 520, on-skin sensor assembly 508, first spring 524, and second spring 526 are all shown in their pre-actuation positions.

[0117] The retaining element 532 of the holder 704 contacts the inner housing 506, thereby securing the holder 704, and therefore the needle carrier assembly 702, needle hub 518, insertion element 520, and on-skin sensor assembly 508, in the pre-activated state.

[0118] The backstop feature 712 of the needle carrier assembly 702 contacts the spring retaining element 710 to prevent the spring retaining element 710 from deflecting laterally, thereby ensuring that the spring retaining element 710 retains the tang 708 of the second spring 706 in the loaded or pre-actuated position shown.

[0119] Actuation of the applicator 700 may involve the host pressing the applicator 700 against their skin with sufficient force to translate the outer housing 504 distally toward and relative to the inner housing 506 until the actuation element 502 is aligned with the insertion assembly retaining element 532 of the holder 704, as shown in FIG. 21 . Once such alignment is achieved, the host may initiate the actuation element 502, thereby sufficiently deflecting the insertion assembly retaining element 532 to release the holder 704 from the inner housing 506. In some other embodiments, the applicator 700 may be configured such that the actuation element 502 may be first actuated, but the actual insertion is not triggered until the outer housing 504 has been sufficiently translated distally toward and relative to the inner housing 506. In yet other embodiments, the actuating element 502 may be biased toward the center of the applicator 700 such that the actuating element 502 does not need to be explicitly actuated by the host, but instead may be configured to automatically begin insertion when the outer housing 504 is sufficiently translated distally toward and relative to the inner housing 506.

[0120] 22 shows the applicator 700 after actuation and during insertion, according to some embodiments. The first spring 524 drives the holder 704, and thus the needle carrier assembly 702, needle hub 518, insertion element 520, and on-skin sensor assembly 508, distally toward the distal insertion position. FIG. 22 shows the on-skin sensor assembly 508 in contact with the host's skin, but with the holder 704 not yet fully driven by the first spring 524 into contact with the on-skin sensor assembly 508 or the host's skin.

[0121] In some embodiments, the mass of each of the holder 704, needle carrier assembly 702, needle hub 518, insertion element 520, and on-skin sensor assembly 508 may be specifically designed to reduce or substantially eliminate the tendency of the needle carrier assembly 702, needle hub 518, insertion element 520, and on-skin sensor assembly 508 to detach from the holder 704 while being driven distally during insertion. In some embodiments, the force exerted by the first spring 524 may further be selected to be sufficient for proper operation of the applicator 500, but not so great as to further exacerbate such inertia-triggered detachment described above. In some embodiments, the spring (not shown) may be configured to exert a force against a portion of the needle carrier assembly 702, e.g., in a distal direction, sufficient to prevent inertia-triggered detachment of the needle carrier assembly 516 from the holder 704 during insertion.

[0122] 23 shows the applicator 700 after actuation and at or near the distal insertion position, according to some embodiments. The first spring 524 drives the holder 704, needle carrier assembly 702, and on-skin sensor assembly 508 distally to the distal insertion position. Because the first spring 524 has driven the holder 704 a shorter distance distally than the needle carrier assembly 702, the backstop feature 712 no longer contacts the spring retaining element 710, allowing the second spring 706 (e.g., tang 708) to deflect the spring retaining element 710 laterally, thereby releasing the second spring 706 and driving the needle carrier assembly 702 proximally. Alternatively, similar to that described above in connection with applicator 500 of FIG. 13 , where angle θ of the portion of spring retaining element 710 that contacts tang 708 of second spring 526 is substantially 90° (e.g., flat), spring retaining element 710 may be biased to automatically deflect sufficiently to release second spring 706 when backstop feature 712 no longer contacts spring retaining element 710, thereby releasing second spring 526 and driving needle carrier assembly 702 in a proximal direction. Although not shown in FIGS. 21-23 , inner housing 506 may further comprise engagement element 550 configured to engage protrusion 552 of needle carrier assembly 702 and function substantially at least as described above in connection with FIGS. 10-12 . In some examples, a stop feature (not shown) may be located on the bottom of applicator 700, for example, on a distal portion of inner housing 506. Such a stop feature may be configured to contact one or more of the on-skin sensor assembly 508, the needle carrier assembly 702, or the holder 704 at the distal insertion position.

[0123] When the second spring 706 is released, the second spring 706 is configured to drive the needle carrier assembly 702, the needle hub 518, and the insertion element 520 in a proximal direction. Although not shown in FIG. 23 , when the needle carrier assembly 702 moves to the proximal retracted position, the needle carrier retaining element 542 can engage the needle carrier assembly 702, thereby retaining the needle carrier assembly 702, the needle hub 518, and the insertion element 520 in a locked retracted position that restricts access to the insertion element 520.

[0124] 24 illustrates a perspective view of the holder 704, first spring 524, and second spring 706 of the applicator 700, according to some embodiments. FIG. 24 illustrates the spring retaining element 710 with the retaining tangs 708 of the second spring 706 oriented within the applicator 700 prior to retraction.

[0125] During manufacture, the applicator 700 may be assembled in stages. For example, but not by way of limitation, the first barrier layer 512 (see FIG. 6 ), if present, may be attached to the inner housing 506, as described above in connection with the applicator 500. The insertion element 520 may be coupled to the needle hub 518, which may then be coupled to the on-skin sensor assembly 508. The second spring may be installed in the holder 704 or the needle carrier assembly 702, and the needle carrier assembly 702 may then be placed in the holder 704 and attached to the needle hub 518 and the on-skin sensor assembly via the wearable retention elements 534 a, 534 b. The first spring 524 may be placed in the holder 704, and then installed in the inner housing 506. The inner housing 506 may be inserted into and secured to the outer housing 504. If present, second barrier layer 530 (see FIG. 6 ) may be attached to inner housing 506, as described above in connection with applicator 500. If a separate element, actuation element 502 may be disposed within outer housing 504. Any labeling, sterilization, and / or packaging may then be applied to applicator 700.

[0126] In some embodiments, the applicator system may include a cap and / or liner removal component. FIG. 25 illustrates, for example, an embodiment of an applicator 900 having an applicator housing 902 configured to hold an on-skin medical device and a deployment mechanism configured to deploy the on-skin medical device to the skin. The applicator housing 902 may be configured similarly to the applicator embodiments disclosed herein, including having an outer housing 904 and an inner housing 906 as disclosed with respect to the embodiments of FIGS. 5-24 . The outer housing 904 may be configured similarly to the outer housing 504, and the inner housing may be configured similarly to the inner housing 506. The applicator housing 902, in some embodiments, may be configured to be grasped by a user. Various other configurations of the applicator housing may be utilized as desired.

[0127] The applicator housing 902 may include an internal cavity 903 for holding a skin-mountable medical device. The housing 902 may include an opening 905 at an end portion 907 of the internal cavity 903 for deploying the skin-mountable medical device therethrough. The internal cavity 903 may include a proximal end portion 909 that may include a skin-mountable medical device coupled to a needle carrier assembly.

[0128] The deployment mechanism may be configured similarly to other forms of deployment mechanisms disclosed herein. The deployment mechanism may be configured similarly to the deployment mechanisms disclosed with respect to the embodiments of FIGS. 5-24. For example, the deployment mechanism, in embodiments, may include an engagement portion in the form of one or more retention elements for retaining the on-skin-wearable medical device and releasing the on-skin-wearable medical device from the housing 902 onto the skin. The deployment mechanism may include an insertion assembly for inserting at least a portion of the on-skin-wearable medical device into the skin. The insertion assembly may insert an insertion element (e.g., a needle) into the skin. The deployment mechanism may drive the insertion element into the skin as the deployment mechanism deploys the on-skin-wearable medical device onto the skin. The deployment mechanism may include a retraction assembly for retracting the insertion element from the skin. Other forms of deployment mechanisms may be utilized in embodiments as desired.

[0129] Applicator 900 may include actuation element 908, which may operate similarly to actuation element 502. Applicator 900 may include needle carrier assembly 910, which may operate similarly to needle carrier assembly 516. Applicator 900 may include holder 912, which may operate similarly to holder 522. Applicator 900 may include a hub (e.g., needle hub 914), which may operate similarly to needle hub 518. Applicator 900 may include insertion element 915 (e.g., a needle), which may operate similarly to insertion element 520. Applicator 900 may include springs 916 and 918, which may operate similarly to springs 524 and 526, respectively. Applicator 900 may include retention elements 920a and 920b, which may operate similarly to retention elements 534a and 534b, respectively. Additional components of the applicator shown in FIGS. 5-24 may be utilized with applicator 900. Applicator 900 may operate in a similar manner and provide similar functionality to the applicators shown in Figures 5-24.

[0130] The applicator 900 may include a cap 942 that may be positioned at a distal portion of the applicator housing 902 and may cover a distal opening 905 of the internal cavity 903. The cap 942 may include a gripping portion 944 on an outer surface of the cap 942 and an engaging portion 946 on an inner surface of the cap 942. The cap 942 may include a central portion 948 that covers and spans the distal opening 905 of the internal cavity. The cap 942 may include an outer lid for the applicator 900 during shipping and unpackaging of the applicator 900.

[0131] A central portion 948 of cap 942 may include one or more openings 950 that may allow a sterilizing substance, such as a sterilizing gas, to pass through to sterilize the internal components of applicator 900. Central portion 948 may include a central support 952 that may be configured to press against liner removal component 928 to hold liner removal component 928 in place. Central support 952 may be configured to rotate when disconnecting or unscrewing cap 942 from applicator housing 902.

[0132] An engagement portion 946 of the cap 942 may include threads or another form of engagement portion 946 for engaging a corresponding engagement portion 954 on the exterior surface of the housing 902. The engagement portion 946 may be configured to be rotated relative to the applicator housing 902 to unscrew from the housing 902 and enable release of the liner removal component 928 from the applicator housing 902.

[0133] The applicator 900 may include a liner removal component 928. The liner removal component 928 may be configured to engage with a liner 926 positioned on the engagement surface of the patch 922 and remove the liner 926 from the engagement surface of the on-skin medical device when pulled from the engagement surface of the on-skin medical device. The liner removal component 928 may include an engagement surface 930 for engaging with the liner 926. The engagement surface 930 may be a flat surface that may extend parallel to the liner 926. The engagement surface 930 may include an opening 927 configured to allow the insertion element 915 to pass through. The liner removal component 928 may further include a sheath 939 configured to cover the insertion element 915. The liner removal component 928 may further include a raised portion 936 that may extend from a distal portion 932 of the liner removal component 928. The raised portion 936 may extend axially within the internal cavity 903.

[0134] A distal portion 932 of the liner removal component 928 may include a flange 933 for grasping by a user to remove the liner removal component 928 from the internal cavity 903 and thus remove the liner 926 from the engagement surface of the on-skin medical device. In an embodiment, the flange 933 may be omitted from use.

[0135] In some embodiments, a liner 926 may be positioned over the engaging surface of the patch. The liner may cover the engaging surface and protect it from damage, degradation, or other adverse effects. The liner may include, for example, a sheet of material that covers the engaging surface of the patch. The liner may have a proximal surface that contacts the engaging surface of the patch and a distal surface facing opposite the proximal surface. In some embodiments, the liner may be configured to reduce the likelihood that the exposed engaging surface will degrade or otherwise lose its adhesive properties prior to deployment. For example, during a sterilization process using a gas or other sterilizing material, the liner may reduce the likelihood of the engaging surface degrading. The sterilizing gas may include ethylene oxide (EtO) or another form of sterilizing gas as desired. However, the liner should be removed from the engaging surface before deploying the on-skin sensor assembly on the skin.

[0136] The applicator 900 may be utilized to deploy an on-skin medical device on the skin. The on-skin medical device may include, for example, the on-skin sensor assembly 508 shown in FIG. 6, which may include a housing, an analyte sensor coupled to the housing, an electronics unit, and a patch 922. The on-skin sensor assembly may have a configuration such as that shown in FIGS. 2A-4, or other configurations as desired.

[0137] The cap 942 and liner removal component 928 may be removed prior to deployment of the on-skin medical device onto the skin.

[0138] When activated, the applicators disclosed herein can utilize an insertion element (such as insertion element 915) to insert a transcutaneous analyte sensor into the skin of a host.

[0139] Referring to FIG. 26A, the insertion element 915 can drive the analyte sensor 956 of the on-skin sensor assembly 508 into the skin of the host, with the analyte sensor 956 extending along the channel 958 of the insertion element 915.

[0140] The analyte sensor 956 may include, for example, a first portion 960 or contact portion that may be coupled to a housing 962 of the on-skin sensor assembly 508. The first portion 960 may include electrical contacts 964 that may be electrically connected to, for example, an electrical terminal of the on-skin sensor assembly 508 or another component of the on-skin sensor assembly 508. The electrical terminal may be positioned on an interface board or circuit board, or another component of the on-skin sensor assembly 508, as desired. Other methods of coupling between the first portion 960 and the housing 962 may be utilized, as desired.

[0141] Analyte sensor 956 can include a second portion 966 including a sensing portion, which can be configured to be inserted into or through the skin of a host and positioned intracutaneously or subcutaneously. Second portion 966, in embodiments, can extend distally from a distal surface 968 of housing 962 and can be guided into the host's skin by insertion element 915. Second portion 966 can be straight and axially aligned with opening 978 for passage of insertion element 915, as shown in FIG. 26A .

[0142] The analyte sensor 956 may include an elongated analyte sensor. The second portion 966 may extend distally to be positioned within the host's skin layer. In embodiments, the second portion 966 of the analyte sensor 956 may extend perpendicular to the distal surface 968 of the housing 962. In embodiments, other angles may be utilized as desired. The second portion 966 may extend perpendicular to the first portion 960 of the analyte sensor 956. In embodiments, other angles may be utilized as desired.

[0143] The bend 970 may angle the second portion 966 of the analyte sensor 956 relative to the first portion 960 of the analyte sensor 956. The bend 970 may be positioned, for example, between the second portion 966 and the first portion 960 and may have a continuous curve, as shown in FIG. 26A , or may have another configuration as desired. The bend 970 may angle the second portion 966 at a perpendicular angle relative to the first portion 960 or at another angle as desired. The bend 970 may be axially aligned with an opening 978 for passage of the insert element 915, as shown in FIG. 26A . Other configurations of the analyte sensor 956 may be utilized as desired.

[0144] The housing 962 of the on-skin sensor assembly 508 may be configured similarly to other forms of housing disclosed herein. The housing 962 may include a wearable housing. The housing 962 may be configured to be worn on the skin of a host. The housing 962 may include a distal surface 968 that may be configured to face toward the skin of the host. The patch 922 may be positioned on the distal surface 968 of the housing 962. The patch 922 may include an engagement surface 974 for engaging the skin of the host. The engagement surface 974 may include an adhesive surface, or another form of surface, in some embodiments.

[0145] The housing 962 may include a proximal surface 972 facing opposite the distal surface 968. The proximal surface 972 may extend parallel to the distal surface 968 or may have another configuration as desired.

[0146] The housing 962, in some embodiments, may include a cavity 976 that may receive the first portion 960 of the analyte sensor 956. The cavity 976 may have various configurations as desired. For example, the cavity 976, in some embodiments, may be configured to hold an adhesive (which may include a liquid adhesive or a curable adhesive) that may couple the first portion 960 of the analyte sensor 956 to the housing 962. The cavity 976 may hold the adhesive and, if desired, may include one or more dams or other features that may be utilized to electrically isolate portions of the analyte sensor 956 from each other. In some embodiments, the cavity 976 may comprise a recess for the first portion 960 of the analyte sensor 956 to be inserted into and otherwise coupled to the housing 962. In some embodiments, the use of the cavity 976 may be eliminated, and the first portion 960 of the analyte sensor 956 may be coupled to the housing 962 in other ways.

[0147] The housing 962 can include an opening 978 for the insertion element 915 to pass through. The opening 978 can extend through the proximal surface 972 of the housing 962 and can extend to the distal surface 968 of the housing 962. The opening 978 can be configured to retract the insertion element 915 proximally through the skin. The insertion element 915 can be retracted after penetrating the host's skin. In embodiments, the insertion element 915 can be positioned within the opening 978 during insertion into the host's skin, or can be threaded distally relative to the opening 978 during insertion into the host's skin. In embodiments such as shown in FIG. 26A , the insertion element 915 can be positioned within the opening 978 and can be static relative to the opening 978 during insertion into the host's skin. For example, as shown in Figures 7, 8 and 21-23, the insertion element 915 may move distally with the housing 962 of the on-skin sensor assembly 508 and may remain stationary relative to the housing 962 upon insertion into the host's skin. Other forms of insertion may be utilized in embodiments.

[0148] The insertion element 915 can include a proximal end portion 980 and a distal end portion 982 that comprises a tip 984 of the insertion element 915. The tip 984, in embodiments, can include a sharp tip and can be configured to pierce and be inserted into the host's skin.

[0149] The needle hub 914 may be positioned at a proximal end portion 980 of the insertion element 915. The needle hub 914 may contact the proximal surface 972 of the housing 962 or may be spaced from the proximal surface 972 as desired.

[0150] 27 shows a perspective view of an on-skin wearable medical device in the form of an on-skin sensor assembly 508. The wearable housing 509 of the on-skin sensor assembly 508 is shown, with the patch 922 (marked in FIG. 25) removed from the illustration for clarity.

[0151] The wearable housing 509 has a diameter 511 and a height 513 (marked in FIG. 27). The wearable housing 509 may further include one or more outer surfaces 515 having a contour that defines the shape of the wearable housing 509. The wearable housing 509 includes an outer top, upper, or proximal surface 517 having a shape (e.g., a flat shape as shown in FIG. 27). The wearable housing 509 includes an outer lower, bottom, or distal surface 519 having a predetermined shape. The distance from the outer top surface 517 to the outer lower surface 519 of the housing 509 may comprise the height 513 of the housing 509.

[0152] The wearable housing 509 may further include one or more mating features 521 that may be configured to engage a mating portion of an applicator. The mating features 521 may have a variety of forms and may include recesses as shown in FIG. 27. Other forms of mating features (e.g., protrusions, adhesives) may be utilized in embodiments as desired. The mating features 521 may be positioned on one or more exterior surfaces 515 of the housing 509 or may have other locations in embodiments as desired. The mating features 521 may be configured to engage a mating portion of the applicator, which may be in the form of wearable retention and / or alignment elements 534a, 534b as shown in FIGS. 15 and 16, for example.

[0153] In embodiments, stabilizing features 523 may be provided that may stabilize the wearable housing 509 within the applicator. The stabilizing features 523 may, for example, comprise recesses in one or more of the outer sides 515 that may mate with stabilizers on the applicator. The stabilizers may contact the stabilizing features 523 to prevent removal or other movement of the on-skin sensor assembly 508 within the applicator.

[0154] The configuration of the on-skin sensor assembly 508 may be compatible with the applicator (e.g., the applicators disclosed herein, including applicators 500, 700). For example, the size of the on-skin sensor assembly 508 (e.g., the diameter 511 and / or height 513 of the wearable housing 509) may be compatible with the applicator and may be compatible with an engaging portion of the applicator. For example, an engaging portion in the form of wearable retention and / or alignment elements 534a, 534b as shown in FIGS. 15 and 16 may be sized and otherwise configured to engage with the wearable housing 509 of the on-skin sensor assembly 508.

[0155] The location and shape of the mating feature 521 may be further configured to engage a mating portion of an applicator. For example, the mating feature 521 may be positioned, shaped, or otherwise configured to receive the wearable retention and / or alignment elements 534a, 534b therein, as shown in Figures 15 and 16. The stabilizing feature 523 may be further positioned, shaped, or otherwise configured to mate with a stabilizer on the applicator.

[0156] Thus, an applicator (e.g., any applicator disclosed herein, including applicators 500, 700) may be configured to engage and deploy the on-skin sensor assembly 508 shown in Figure 27. The engaging portion of the applicator (e.g., the wearable retention and / or alignment elements 534a, 534b as shown in Figures 15 and 16) may fit over the on-skin sensor assembly 508.

[0157] However, other forms of on-skin wearable medical devices may be utilized in examples. For example, Fig. 28 shows a perspective view of an on-skin wearable medical device having a different configuration than the on-skin wearable medical device shown in Fig. 27. Fig. 28 shows an on-skin wearable medical device in the form of an on-skin sensor assembly 1000. The wearable housing 1002 of the on-skin sensor assembly 1000 is shown (the patch has been omitted from the illustration for clarity). The patch may have a configuration similar to other configurations of patches disclosed herein or may have other configurations as desired.

[0158] The wearable housing 1002 may have a diameter 1004 and a height 1006. The wearable housing 1002 may further include one or more outer surfaces 1008 having a contour that defines the shape of the wearable housing 1002. The wearable housing 1002 includes an outer upper, top, or proximal surface 1010 having a predetermined shape (e.g., a flat shape as shown in FIG. 28 ). The wearable housing 1002 includes an outer lower, bottom, or distal surface 1012 having a predetermined shape. The distance from the outer upper surface 1010 to the outer lower surface 1012 of the housing 1002 may comprise the height 1006 of the housing 1002.

[0159] The wearable housing 1002 may further include one or more mating features 1014. The mating features 1014 may have a variety of forms and may include recesses as shown in FIG. 28. Other forms of mating features (e.g., protrusions, adhesives) may be utilized in embodiments as desired. The mating features 1014 may be positioned on one or more exterior surfaces 1008 of the housing 1002, or may have other locations in embodiments as desired.

[0160] The configuration of the on-skin sensor assembly 1000 shown in Figure 28 differs from the configuration of the on-skin sensor assembly 508 shown in Figure 27. For example, the size of the on-skin sensor assembly 1000 differs from the size of the on-skin sensor assembly 508 shown in Figure 27. The diameter 1004 of the housing 1002 is smaller than the diameter 511 of the housing 509, for example. The height 1006 of the housing 1002 is smaller than the height 513 of the housing 509, for example. Although the height and diameter are both shown as different in Figures 27 and 28, in embodiments, one or more of the height or diameter may be different.

[0161] The shape of the on-skin sensor assembly 1000 shown in Figure 28 differs from the shape of the on-skin sensor assembly 508 shown in Figure 27. For example, the on-skin sensor assembly 508 shown in Figure 27 has a wider end and a narrower end, while the on-skin sensor assembly 1000 shown in Figure 28 has ends with the same width. The on-skin sensor assembly 1000 may have an oval or elliptical shape, and the on-skin sensor assembly 508 of Figure 27 may have an oval shape with one end wider than the other.

[0162] The configuration of the on-skin sensor assembly 1000 shown in Figure 28 may differ from the configuration of the on-skin sensor assembly 508 shown in Figure 27 in that the size, location, or other configuration of the coupling features may differ. The coupling feature 521 shown in Figure 27 may be located at an end portion of the wearable housing 509, for example. The coupling feature 1014 shown in Figure 28 may be located at a central portion of the wearable housing 1002. The configuration of the on-skin sensor assembly 1000 shown in Figure 28 may differ from the configuration of the on-skin sensor assembly 508 shown in Figure 27 in other ways, as desired.

[0163] Thus, the on-skin sensor assembly 1000 may have a mating mismatch with an applicator (e.g., an applicator disclosed herein, including applicators 500, 700). While the applicator may be configured to mate with the on-skin sensor assembly 508 shown in FIG. 27, variations in the configuration of the on-skin sensor assembly 1000 shown in FIG. 28 may cause the applicator to not mate with the on-skin sensor assembly 1000. For example, with reference to FIGS. 15 and 16, engagement portions in the form of wearable retention and / or alignment elements 534a, 534b may not be configured to engage with the on-skin sensor assembly 1000.

[0164] 29A , in an embodiment, an adapter body 1020 may be utilized. The adapter body 1020 may be configured to interface between at least a portion of the on-skin medical device and an applicator. The adapter body 1020 may, for example, be adapted to mate with at least a portion of the on-skin medical device to an engagement portion of the applicator. For example, with reference to FIGS. 27 and 28 , the adapter body 1020 may enable the on-skin sensor assembly 1000 to mate with an engagement portion of the applicator configured to mate with the on-skin sensor assembly 508. The engagement portion may be configured to engage the adapter body 1020.

[0165] In examples, the adapter body 1020 may be configured to interface in various ways. For example, the adapter body 1020 may interface between a portion of the on-skin sensor assembly 1000 having a first configuration (as shown in FIG. 28 ) and a portion of the applicator (e.g., an engaging portion as shown in FIGS. 15 and 16 ) configured to engage a second configuration of the on-skin sensor assembly 508 (as shown in FIG. 27 ) that differs from the first configuration. The configurations may differ from each other in one or more of shape or size, or other configurations (e.g., location or shape of coupling features). The configurations may be of the respective wearable housing 509, 1002 or other portions of the assembly 508, 1000.

[0166] In an example, the on-skin sensor assembly 1000 may be smaller than the on-skin sensor assembly 508. The size difference may be a difference in size between the housings 509, 1002 of the on-skin sensor assemblies 508, 1000. For example, a smaller diameter or a smaller height of the housing 1002 may be provided. Accordingly, the adapter body 1020 may comprise a spacer body configured to space the size difference between the on-skin sensor assemblies 508, 1000. Other forms of interfaces may be utilized in embodiments.

[0167] In an example, the adapter body 1020 may be configured to accommodate an on-skin wearable medical device that may be modified or adjusted from a first configuration to a second configuration. For example, the on-skin wearable medical device may have added or removed components or modules, or other modifications to the on-skin wearable medical device, that may change the configuration of the on-skin wearable medical device for engagement with the applicator. The added or removed components or modules may include electrical components or modules (e.g., communication components, power sources such as batteries, sensing components, processors, among others), or other configurations of components or modules. The changes to the on-skin wearable medical device may change the shape, size, or other configuration of the on-skin wearable medical device (e.g., the location or shape of coupling features) from the first configuration to the second configuration. Thus, an on-skin wearable medical device having a first configuration may be the same as an on-skin wearable medical device having a second configuration. The adapter body 1020 may be configured to interface between an on-skin device having a second configuration and an applicator (while the applicator may be configured to engage the same on-skin device having a first configuration without the use of the adapter body 1020). Other uses of the adapter body 1020 may result.

[0168] 29A and 29B, the adapter body 1020 can include a holding area 1022 for receiving at least a portion of the on-skin medical device. The holding area 1022 can, for example, comprise a cavity for receiving at least a portion of the on-skin medical device.

[0169] The adapter body 1020 may include one or more walls that may define a boundary of the holding area 1022. The one or more walls may include one or more side walls 1024 that may define the boundary of the holding area 1022. The side walls 1024 may be configured to cover corresponding sides 1008 (marked in FIG. 28 ) of the on-skin sensor assembly 1000.

[0170] The side wall 1024 may include an inner surface 1026 (marked in FIG. 29B ) and an outer surface 1028. The inner surface 1026 may be configured to face toward a portion of the on-skin medical device that may be positioned within the retention area 1022. The outer surface 1028 may be configured to face opposite the inner surface 1026 and may face radially outward from the on-skin medical device.

[0171] The one or more side walls 1024 may have a spacing between the inner surface 1026 and the outer surface 1028, which may be configured to space the outer surface 1008 of the on-skin medical device (marked in FIG. 28 ) from the outer surface 1028 of the one or more side walls 1024. The outer surface 1008 of the on-skin medical device may comprise, for example, the outer surface 1008 of the housing 1002. The thickness of the one or more side walls 1024 may form the spacing, or the spacing may be provided in other ways.

[0172] The inner surface 1026 may be configured to contact the outer surface 1008 of the on-skin medical device. The inner surface 1026 may be contoured to the shape of the outer surface 1008 of the on-skin medical device to provide a contour that matches the shape of the outer surface 1008. The outer surface 1028 of the adapter body 1020 may have a different contour than the inner surface 1026 of the adapter body 1020 in some embodiments.

[0173] For example, the inner surface 1026 may form the inner periphery 1030 of the adapter body 1020. The outer surface 1028 may form the outer periphery 1032 of the adapter body 1020. The inner periphery 1030 may have a different contour than the outer periphery 1032. Such a feature may account for differences in shape between the outer surface 1008 of the on-skin sensor assembly 1000 and the shape to which the adapter body 1020 conforms the on-skin sensor assembly 1000. For example, if the engaging portion of the applicator is configured to fit a square and the outer surface 1008 of the on-skin sensor assembly 1000 has an oval shape, the outer periphery 1032 may have a square contour. However, the inner periphery 1030 may retain its oval shape to accommodate the shape of the outer surface 1008 of the on-skin sensor assembly 1000. The inner periphery 1030 may, in embodiments, have a smaller diameter than the outer periphery 1032. The engaging portion may be configured to engage at least a portion of one or more walls of the adapter body. The engagement portion may be configured to engage an outer surface of the adapter body.

[0174] The spacing between the inner surface 1026 and the outer surface 1028 can accommodate an on-skin wearable medical device to fit into the engagement portion of the applicator. For example, the engagement portion of the applicator may be configured to engage an on-skin sensor assembly having a larger diameter than the on-skin sensor assembly 1000. The spacing can compensate for the difference in diameter. Alternatively, or in combination, the spacing can compensate for the difference in shape between the on-skin sensor assemblies.

[0175] The one or more walls may include an upper wall 1034 that may define the boundary of the retention area 1022. The upper wall 1034 may be configured to cover a corresponding outer top, upper, or proximal surface 1010 (marked in FIG. 28 ) of the on-skin medical device. The upper wall 1034 may include an inner surface 1036 (marked in FIG. 29B ) and an outer surface 1038. The inner surface 1036 may be configured to face toward a portion of the on-skin medical device that may be positioned within the retention area 1022. The outer surface 1038 may be configured to face opposite the inner surface 1036 and may face radially outward from the on-skin medical device.

[0176] The top wall 1034 may have a spacing between its inner surface 1036 and outer surface 1038 that may be configured to space an outer top, upper, or proximal surface 1010 (shown in FIG. 28 ) of the on-skin medical device from the outer surface 1038 of the top wall 1034. The outer surface 1010 of the on-skin medical device may comprise, for example, the outer top surface 1010 of the housing 1002. The thickness of the top wall 1034 may form the spacing, or the spacing may be provided in other ways. The top wall 1034 may include an opening 1035 that may allow for the insertion or retraction of an insertion element, such as a needle.

[0177] The inner surface 1036 may be configured to contact the outer surface 1010 of the on-skin medical device. The inner surface 1036 may be contoured to the shape of the outer surface 1010 of the on-skin medical device to provide a contour that matches the shape of the outer surface 1010. The outer top surface 1038 of the adapter body 1020, in examples, may have a different contour than the inner surface 1036 of the adapter body 1020.

[0178] The spacing between the inner surface 1036 and the outer surface 1038 can accommodate an on-skin wearable medical device to fit into the engagement portion of the applicator. For example, the engagement portion of the applicator may be configured to engage an on-skin sensor assembly having a greater height than the on-skin sensor assembly 1000. The spacing can compensate for the height difference. Alternatively, or in combination, the spacing can compensate for shape differences between the on-skin sensor assemblies.

[0179] In some embodiments, the side wall 1024 can extend distally from the top wall 1034. In some embodiments, the side wall 1024 can extend distally from an outer edge or perimeter of the top wall 1034. Other configurations can be provided in some embodiments.

[0180] One or more stabilizers 1040 may be provided to stabilize the on-skin medical device within the holding area 1022. The stabilizers may comprise protrusions, for example, as shown in FIG. 29B . In embodiments, the stabilizers may have other forms. The stabilizers may be configured to contact the on-skin medical device to prevent the on-skin device from moving within the holding area 1022. For example, lateral movement may be resisted. The stabilizers 1040 may comprise one or more portions of the side walls 1024, including the inner surface 1026 of the side walls 1024.

[0181] 29A and 29B , the outer surface 1028 of the sidewall 1024 may include a stabilizing feature 1042 that may be configured to stabilize the adapter body 1020 within the applicator. The stabilizing feature 1042 may comprise a recess in the outer surface 1028 of the sidewall 1024. The stabilizing feature 1042 may have a similar contour and position to the stabilizing feature 523 shown in FIG. 27 , for example. Thus, the stabilizing feature 1042 may be utilized to stabilize the adapter body 1020 in a manner similar to how the stabilizing feature 523 stabilizes the on-skin sensor assembly 508 within the applicator. Other configurations of stabilizing features may be utilized as desired.

[0182] The adapter body 1020 may include a retainer portion 1044 for holding an on-skin medical device to the adapter body 1020. The retainer portion 1044 may have a variety of configurations. In an example, the retainer portion 1044 may include one or more device couplers 1046 that may couple the on-skin medical device to the adapter body 1020.

[0183] The device coupler 1046 may have various configurations in embodiments. With reference to FIG. 29B , the device coupler 1046 may include a protrusion 1048 that may be configured to engage with the on-skin sensor assembly 1000. The protrusion 1048 may be configured to engage a mating feature 1014 on the wearable housing 1002 of the on-skin sensor assembly 1000 (e.g., as shown in the detailed view of FIG. 30C ). The protrusion 1048 may enter the mating feature 1014 in the form of a recess in the wearable housing 1002. The device coupler 1046 may have other forms in embodiments. For example, the device coupler may include a protrusion or a recess, or one or more of a protrusion or a recess. The device coupler may include an adhesive or have another form.

[0184] The device coupler 1046 may be located at an edge portion of the top wall 1034, which in an embodiment may include a portion of the side wall 1024 of the adapter body 1020. The device coupler 1046 may have other locations in embodiments.

[0185] The device coupler 1046 may include a releasable coupler configured to release the on-skin wearable medical device from the adapter body 1020. The device coupler 1046 may be configured to deflect, for example, to release the on-skin wearable medical device from the adapter body 1020. The deflection may be in a radially outward direction to allow the device coupler 1046 to separate from the on-skin wearable medical device.

[0186] The device coupler 1046 may include an arm, in an embodiment. For example, the arm 1050 may extend distally from the top wall 1034. The end of the arm 1050 may include a protrusion 1048. The arm 1050 may be coupled to the top wall 1034 by a hinge portion 1052. For example, with reference to FIG. 30C , the hinge portion 1052 may allow the arm 1050 to flex radially outward from the wearable housing 1002. The hinge portion 1052 may be configured to pivot about an axis extending parallel to the plane of the adapter body 1020 (e.g., the plane of the top wall 1034).

[0187] The arms 1050, in an embodiment, can define the boundaries of the retention area 1022. The arms 1050 can flex radially outward from the retention area 1022 to allow release of the on-skin medical device from the retention area 1022 of the adapter body 1020.

[0188] In embodiments, the adapter body 1020 may include one or more supports 1054. The supports 1054 may be configured to support the device coupler 1046 in a coupled configuration with the on-skin medical device. The supports 1054 may have various forms and may comprise a contact surface of the adapter body 1020. The contact surface may be configured to contact a contact surface 1056 of an applicator (marked in FIG. 30A ) to press the device coupler 1046 toward the on-skin medical device. The contact surface 1056 may abut against a contact surface of the support 1054. Thus, the device coupler 1046 may be held in a coupled configuration with the on-skin medical device. The support 1054 may have other configurations in embodiments.

[0189] 29A and 29B, an applicator coupler 1060 may be utilized to couple the adapter body 1020 to at least a portion of the applicator. The applicator coupler 1060 may include a protrusion that may engage the applicator. The applicator coupler 1060 may also have other configurations, such as a recess or adhesive. In embodiments, one or more protrusions or recesses may be provided. As shown in FIGS. 29A and 29B, the applicator coupler 1060 may protrude radially outward from the outer surface 1028 of one or more sidewalls 1024.

[0190] 29C shows a top view of the adapter body 1020 positioned on the on-skin sensor assembly 1000. The spacing of the outer surface 1028 of the side wall 1024 from the outer surface 1008 of the wearable housing 1002 is visible.

[0191] FIG. 30A shows adapter body 1020 coupled to an applicator. An engagement portion of the applicator, e.g., wearable retention elements 534a-d, may engage sidewall 1024 of adapter body 1020. The contact surface of sidewall 1024 may be located in the same position as coupling mechanism 521 shown in FIG. 27 where it engages with wearable retention elements 534a-d. The applicator includes stabilizer 1070 that mates with stabilizing feature 1042 of adapter body 1020. Stabilizer 1070 may include, for example, a portion of needle carrier assembly 516 shown in FIG. 6. Stabilizer 1070 may include one or more posts or may have another form in some embodiments.

[0192] The applicator may further include a stabilizer 1072 having a contact surface 1056 for contacting the support portion 1054 of the adapter body 1020. The stabilizer 1072 may also include, for example, a portion of the needle carrier assembly 516 shown in FIGURE 6. The stabilizer 1072 may include one or more posts or may have another form in some embodiments.

[0193] An insertion element in the form of a needle may extend through an opening 1035 in the top surface of adapter body 1020 .

[0194] 30A, the applicator coupler 1060 may not yet be coupled to the applicator because the deployment mechanism may be in a distal position prior to application to the host's skin. The deployment mechanism may be moved proximally upon contact with the host's skin during the deployment procedure.

[0195] Figure 30B shows the wearable housing 1002 of the on-skin sensor assembly 1000 coupled to the adapter body 1020. A device coupler 1046 may couple the wearable housing 1002 to the adapter body 1020. Figure 30C shows a detailed view of the device coupler 1046 coupled to the wearable housing 1002.

[0196] 30D illustrates exemplary steps during deployment of on-skin sensor assembly 1000 to the host's skin. The applicator may be pressed against the surface of the skin, causing the deployment mechanism to retract proximally. The needle carrier assembly 516 may retract proximally relative to the holder 522, for example. Such movement may allow the applicator coupler 1060 to couple to the applicator. The applicator coupler 1060 may, for example, enter a recess or channel 1073 in the holder 522 to couple to the holder 522.

[0197] The needle carrier assembly 516 may be retracted in the deployment procedure according to the methods disclosed herein. FIG. 30E shows the resulting configuration in which the needle carrier assembly 516 has been retracted. Accordingly, the engagement portion in the form of the wearable retention elements 534a-d may be released from the adapter body 1020 in a manner similar to that disclosed herein with respect to the on-skin sensor assembly 508 (e.g., FIGS. 15 and 16 show exemplary releases). The insertion element in the form of a needle may be retracted. The applicator coupler 1060 may hold the adapter body 1020 to the applicator.

[0198] The stabilizer 1072 (marked in FIG. 30A ), having a contact surface 1056 for contacting the support portion 1054 of the adapter body 1020, may be retracted. Thus, the support portion 1054 may not be supported by the contact surface 1056, and the device coupler 1046 may be configured to deflect radially outward. The outward deflection of the device coupler 1046 may allow the on-skin sensor assembly 1000 to release from the adapter body 1020. The on-skin sensor assembly 1000 may be deployed to the host's skin using an adhesive or other form of engagement with the skin, and thus may remain deployed to the skin upon removal of the applicator from the skin.

[0199] Figure 30F shows the resulting configuration of the applicator and a portion of the adapter body 1020, for example, with the on-skin sensor assembly 1000 released from the adapter body 1020. The adapter body 1020 may be coupled to the applicator, with the applicator coupler 1060 disposed within a recess or channel 1073 in the applicator (e.g., as shown in the detailed view of Figure 30G).

[0200] In embodiments, other configurations of the adapter body may be utilized. Figure 31A shows an example of an adapter body 1080. The adapter body 1080 may include features of the adapter body 1020 unless otherwise stated.

[0201] 31A-31C, for example, the adapter body 1080 can include a holding area 1082 for receiving at least a portion of the on-skin medical device. The holding area 1082 can include, for example, a cavity for receiving at least a portion of the on-skin medical device.

[0202] The adapter body 1080 may include one or more walls that may define a boundary of the holding area 1082. The one or more walls may include one or more side walls 1084 that may define the boundary of the holding area 1082. The side walls 1084 may be configured to cover corresponding sides 1008 (marked in FIG. 28 ) of the on-skin sensor assembly 1000.

[0203] The side wall 1084 may include an inner surface 1086 (marked in FIG. 32B ) and an outer surface 1088 (marked in FIG. 31C ). The inner surface 1086 may be configured to face toward a portion of the on-skin medical device that may be placed within the retention area 1082. The outer surface 1088 may be configured to face opposite the inner surface 1086 and may face radially outward from the on-skin medical device.

[0204] The one or more side walls 1084 may have a spacing between the inner surface 1086 and the outer surface 1088, which may be configured to space the outer surface 1008 (marked in FIG. 28 ) of the on-skin medical device from the outer surface 1088 of the one or more side walls 1084. The thickness of the one or more side walls 1084 may form the spacing, or the spacing may be provided in other ways.

[0205] The inner surface 1086 may be configured to contact the outer surface 1008 of the on-skin medical device. The inner surface 1086 may be contoured to the shape of the outer surface 1008 of the on-skin medical device to provide a contour that matches the shape of the outer surface 1008. The outer surface 1088 of the adapter body 1080 may have a different contour than the inner surface 1086 of the adapter body 1080, in examples.

[0206] For example, the inner surface 1086 may form the inner periphery 1090 (marked in FIG. 31C ) of the adapter body 1080. The outer surface 1088 may form the outer periphery 1092 of the adapter body 1080. The inner periphery 1090 may have a different contour than the outer periphery 1092. Such a feature may allow for a difference in shape between the outer surface 1008 of the on-skin sensor assembly 1000 and the shape to which the adapter body 1080 conforms the on-skin sensor assembly 1000. In an embodiment, the inner periphery 1090 may have a smaller diameter than the outer periphery 1092.

[0207] The spacing between the inner surface 1086 and the outer surface 1088 may adapt the on-skin wearable medical device to fit into the engagement portion of the applicator. For example, the engagement portion of the applicator may be configured to engage an on-skin sensor assembly having a larger diameter than the on-skin sensor assembly 1000. The spacing may compensate for the difference in diameter. Alternatively, or in combination, the spacing may compensate for the difference in shape between the on-skin sensor assemblies.

[0208] The one or more walls may include an upper wall 1094 (marked in FIG. 31A ) that may define the boundary of the retention area 1082. The upper wall 1094 may be configured to cover a corresponding outer top, upper, or proximal surface 1010 (marked in FIG. 28 ) of the on-skin medical device. The upper wall 1094 may include an inner surface 1096 (marked in FIG. 31C ) and an outer surface 1098. The inner surface 1096 may be configured to face toward a portion of the on-skin medical device that may be disposed within the retention area 1082. The outer surface 1098 may be configured to face opposite the inner surface 1096 and may face radially outward from the on-skin medical device.

[0209] The top wall 1094 may have a spacing between its inner surface 1096 and outer surface 1098 that may be configured to space an outer top, upper, or proximal surface 1010 (marked in FIG. 28 ) of the on-skin medical device from the outer surface 1098 of the top wall 1094. The outer surface 1010 of the on-skin medical device may comprise, for example, the outer top surface 1010 of the housing 1002. The thickness of the top wall 1094 may form the spacing, or the spacing may be provided in other ways. The top wall 1094 may include an opening 1095 that may allow for the insertion or retraction of an insertion element, such as a needle.

[0210] The inner surface 1096 may be configured to contact the outer surface 1010 of the on-skin medical device. The inner surface 1096 may be contoured to the shape of the outer surface 1010 of the on-skin medical device to provide a contour that matches the shape of the outer surface 1010. The outer surface 1098 of the adapter body 1020 may have a different contour than the inner surface 1096 of the adapter body 1020, in examples.

[0211] The spacing between the inner surface 1096 and the outer surface 1098 may adapt to fit the on-skin medical device onto the engagement portion of the applicator. For example, the engagement portion of the applicator may be configured to engage an on-skin sensor assembly having a greater height than the on-skin sensor assembly 1000. The spacing may compensate for the height difference. Alternatively, or in combination, the spacing may compensate for shape differences between the on-skin sensor assemblies.

[0212] In some embodiments, the side wall 1084 can extend distally from the top wall 1094. In some embodiments, the side wall 1084 can extend distally from an outer edge or perimeter of the top wall 1094. Other configurations can be provided in some embodiments.

[0213] The adapter body 1080 may include a retainer portion 1104 for holding an on-skin medical device to the adapter body 1080. The retainer portion 1104 may have a variety of configurations. In an embodiment, the retainer portion 1104 may include one or more device couplers 1106 that may couple the on-skin medical device to the adapter body 1080.

[0214] The device coupler 1106 may have various configurations in embodiments. With reference to FIG. 31C , the device coupler 1106 may include a protrusion 1108 that may be configured to engage with the on-skin sensor assembly 1000. The protrusion 1108 may be configured to engage a mating feature 1110 of the wearable housing 1002 of the on-skin sensor assembly 1000, which may have a different configuration than the mating feature shown in FIG. 28 . For example, the mating feature 1110 may be located, for example, at an end portion of the wearable housing 1002. Other locations may be utilized as desired. The protrusion 1108 may enter the mating feature 1110 in the form of a recess in the wearable housing 1002. The device coupler 1106 may have other forms in embodiments. For example, the device coupler may include a protrusion or a recess, or one or more of a protrusion or a recess. The device coupler may include an adhesive or have another form.

[0215] The device coupler 1106 may include arms, in an embodiment. For example, the arms 1120 may extend circumferentially along the outer periphery of the adapter body 1080. The arms 1120 may extend circumferentially from respective hinge portions 1122 to respective ends 1124 of the arms 1120. Each arm 1120 may extend circumferentially along a side of the wearable housing 1002. Each arm 1120 may include a protrusion 1108.

[0216] The hinge portion 1122 may allow the arm 1120 to flex radially outward from the wearable housing 1002. The hinge portion 1122 may be configured to pivot about an axis that extends transversely or perpendicular to the plane of the adapter body 1080 (e.g., the plane of the top wall 1094).

[0217] The arms 1120, in an example embodiment, can define the boundaries of the retention area 1082. The arms 1120 can flex radially outward from the retention area 1082 to allow release of the on-skin medical device from the retention area 1082 of the adapter body 1080.

[0218] The device coupler 1106 may be located at an edge portion of the top wall 1094, which in an embodiment may include a portion of the side wall 1084 of the adapter body 1080. The device coupler 1106 may have other locations in embodiments.

[0219] The device coupler 1106 may include a releasable coupler configured to release the on-skin wearable medical device from the adapter body 1080. The device coupler 1106 may be configured to deflect, for example, to release the on-skin wearable medical device from the adapter body 1080. The deflection may be in a radially outward direction to allow the device coupler 1106 to separate from the on-skin wearable medical device.

[0220] In embodiments, the adapter body 1080 may include one or more supports 1126. The supports 1126 may be configured to support the device coupler 1106 in a coupled configuration with the on-skin medical device. The supports 1126 may have various forms and may comprise a contact surface of the adapter body 1080. The contact surface may be configured to contact a contact surface 1127 of the applicator (marked in FIG. 32B ) to press the device coupler 1106 toward the on-skin medical device. The support portions 1126 may include recesses in the arms 1120 or may have another configuration in embodiments. Thus, the device coupler 1106 may be held in a coupled configuration with the on-skin medical device. The supports 1126 may have other configurations in embodiments.

[0221] The support 1126 may further include a stabilizing feature that may be configured to stabilize the adapter body 1080 within the applicator. The stabilizing feature may operate in a manner similar to other forms of stabilizing features disclosed herein.

[0222] 31A and 31B, an applicator coupler 1128 can be utilized to couple the adapter body 1080 to at least a portion of the applicator. The applicator coupler 1128 can include a protrusion that can engage the applicator. The applicator coupler 1128 can also have other configurations, such as a recess or adhesive. In some embodiments, one or more protrusions or recesses can be provided. As shown in FIGS. 31A and 31B, the applicator coupler 1128 can protrude radially outward from the outer surface 1088 of one or more sidewalls 1084. The applicator coupler 1128 can be disposed on the device coupler 1106 or on the end 1124 of the arm 1120. In some embodiments, other locations can be utilized.

[0223] In an example, the device coupler 1106 may be biased to extend radially outward from the retention area 1082. Figure 31A, for example, shows a top view of the adapter body 1080 showing the device coupler 1106 in a free state (i.e., open configuration) in which the device coupler 1106 extends radially outward. Figure 31B shows a top view of the adapter body 1080 disposed on the wearable housing 1002. Figure 31C shows a bottom view of the adapter body 1080 on the wearable housing 1002 with the device coupler 1106 in the open configuration.

[0224] Figure 31D illustrates a top view of the adapter body 1080 positioned on the wearable housing 1002 with the device coupler 1106 in the closed configuration. Figure 31E shows a bottom view of the adapter body 1080 positioned on the wearable housing 1002 with the device coupler 1106 in the closed configuration.

[0225] FIG. 32A shows an adapter body 1080 coupled to an applicator. An engagement portion of the applicator, for example, wearable retention elements 534a-d, can engage a sidewall 1084 of the adapter body 1080. The contact surface of the sidewall 1084 can be located in the same position as where the coupling mechanism 521 shown in FIG. 27 engages with the wearable retention elements 534a-d. The applicator includes a stabilizer 1070 that mates with the support portion 1126 of the adapter body 1080. The contact between the stabilizer 1070 and the support portion 1126 of the adapter body 1080 is shown in the perspective view of FIG. 32B. The contact can hold the device coupler 1106 in a closed configuration.

[0226] 32A and 32B, the applicator coupler 1128 may not yet be coupled to the applicator because the deployment mechanism may be in a distal position prior to application to the host's skin. The deployment mechanism may be moved proximally upon contact with the host's skin during the deployment procedure.

[0227] 32C, the needle carrier assembly 516 may be retracted in a deployment procedure according to the methods disclosed herein. FIG. 32C illustrates the resulting configuration in which the needle carrier assembly 516 has been retracted. Accordingly, engagement portions in the form of wearable retention elements 534a-d may be released from the adapter body 1080 in a manner similar to that disclosed herein with respect to the on-skin sensor assembly 508 (e.g., FIGS. 15 and 16 show exemplary releases). Retraction of the needle carrier assembly 516 may retract an insertion element in the form of a needle.

[0228] The stabilizer 1070 (marked in FIG. 30A ), which has a contact surface for contacting the support portion 1126 of the adapter body 1080, may be retracted. Thus, the support portion 1126 may not be supported by a contact surface, and the device coupler 1106 may be configured to deflect radially outward. The outward deflection of the device coupler 1106 may allow the on-skin sensor assembly 1000 to release from the adapter body 1080. The on-skin sensor assembly 1000 may be deployed to the host's skin using an adhesive or other form of engagement with the skin, and thus may remain deployed to the skin upon removal of the applicator from the skin.

[0229] The outward deflection of the device coupler 1106 may further couple the applicator coupler 1128 into a recess or channel 1130 (marked in FIG. 32D) in the applicator. Thus, the applicator coupler 1128 may hold the adapter body 1080 to the applicator.

[0230] 32E illustrates the resulting configuration of the applicator and a portion of the adapter body 1080, for example, with the on-skin sensor assembly 1000 released from the adapter body 1080. The adapter body 1080 may be coupled to the applicator, with the applicator coupler 1128 disposed within a recess or channel 1130 in the applicator (e.g., as shown in the detailed view of FIG. 32D).

[0231] In embodiments, other configurations of adapter bodies may be utilized. Figure 33A shows an example of an adapter body 1140. The adapter body 1140 may include features of other configurations of adapter bodies disclosed herein unless otherwise stated.

[0232] 33A-33C, the adapter body 1140 can include a holding area 1142 for receiving at least a portion of the on-skin medical device. The holding area 1142 can include, for example, a cavity for receiving at least a portion of the on-skin medical device.

[0233] The adapter body 1140 may include one or more walls that may define the boundaries of the holding area 1142. The one or more walls may include one or more side walls 1144 that may define the boundaries of the holding area 1142. The side walls 1144 may be configured to cover corresponding sides 1008 (marked in FIG. 28 ) of the on-skin sensor assembly 1000.

[0234] The side wall 1144 may include an inner surface 1146 (marked in FIG. 33C ) and an outer surface 1148. The inner surface 1146 may be configured to face toward a portion of the on-skin medical device that may be placed within the retention area 1142. The outer surface 1148 may be configured to face opposite the inner surface 1146 and may face radially outward from the on-skin medical device.

[0235] The one or more side walls 1144 may have a spacing between the inner surface 1146 and the outer surface 1148, which may be configured to space the outer surface 1008 of the on-skin medical device (marked in FIG. 28 ) from the outer surface 1148 of the one or more side walls 1144. The outer surface 1008 of the on-skin medical device may comprise, for example, the outer surface 1008 of the housing 1002. The spacing may be provided by a distance from the inner side wall 1144a (as shown in FIG. 33C ) relative to the outer side wall 1144b.

[0236] The inner surface 1146 may be configured to contact the outer surface 1008 of the on-skin medical device. The inner surface 1146 may be contoured to the shape of the outer surface 1008 of the on-skin medical device to provide a contour that matches the shape of the outer surface 1008. The outer surface 1148 of the adapter body 1140 may have a different contour than the inner surface 1146 of the adapter body 1140, in an example embodiment.

[0237] For example, the inner surface 1146 may form the inner periphery 1150 of the adapter body 1140. The outer surface 1148 may form the outer periphery 1152 of the adapter body 1140. The inner periphery 1150 may have a different contour than the outer periphery 1152. Such a feature may allow for a difference in shape between the outer surface 1008 of the on-skin sensor assembly 1000 and the shape to which the adapter body 1140 conforms the on-skin sensor assembly 1000. The inner periphery 1150 may, in an embodiment, have a smaller diameter than the outer periphery 1152.

[0238] The spacing between the inner surface 1146 and the outer surface 1148 can accommodate an on-skin wearable medical device to fit into the engagement portion of the applicator. For example, the engagement portion of the applicator may be configured to engage an on-skin sensor assembly having a larger diameter than the on-skin sensor assembly 1000. The spacing can compensate for the difference in diameter. Alternatively, or in combination, the spacing can compensate for the difference in shape between the on-skin sensor assemblies.

[0239] The one or more walls may include an upper wall 1154 that may define the boundary of the retention area 1142. The upper wall 1154 may be configured to cover a corresponding outer upper, top, or proximal surface 1010 (marked in FIG. 28 ) of the on-skin medical device. The upper wall 1154 may include an inner surface 1156 (marked in FIG. 33C ) and an outer surface 1158 (marked in FIG. 33A ). The inner surface 1156 may be configured to face toward a portion of the on-skin medical device that may be disposed within the retention area 1142. The outer surface 1158 may be configured to face opposite the inner surface 1156 and may face radially outward from the on-skin medical device.

[0240] The top wall 1154 may have a spacing between its inner surface 1156 and outer surface 1158 that may be configured to space the outer top, upper, or proximal surface 1010 (shown in FIG. 28 ) of the on-skin medical device from the outer surface 1158 of the top wall 1154. The outer surface 1010 of the on-skin medical device may comprise, for example, the outer top surface 1010 of the housing 1002. The thickness of the top wall 1154 may form the spacing, or the spacing may be provided in other ways. The top wall 1154 may include an opening 1155 that may allow for the insertion or retraction of an insertion element, such as a needle.

[0241] The inner surface 1156 may be configured to contact the outer surface 1010 of the on-skin medical device. The inner surface 1156 may be contoured to the shape of the outer surface 1010 of the on-skin medical device to provide a contour that matches the shape of the outer surface 1010. The outer upper surface 1158 of the adapter body 1140, in examples, may have a different contour than the inner surface 1156 of the adapter body 1140.

[0242] The spacing between the inner surface 1156 and the outer surface 1158 can accommodate an on-skin wearable medical device to fit into the engagement portion of the applicator. For example, the engagement portion of the applicator may be configured to engage an on-skin sensor assembly having a greater height than the on-skin sensor assembly 1000. The spacing can compensate for the height difference. Alternatively, or in combination, the spacing can compensate for shape differences between the on-skin sensor assemblies.

[0243] In some embodiments, the side wall 1144 can extend distally from the top wall 1154. In some embodiments, the side wall 1144 can extend distally from an outer edge or periphery of the top wall 1154. Other configurations can be provided in some embodiments.

[0244] In examples, the adapter body 1140 may include an ejection portion 1160 that may be configured to eject the on-skin-wearable medical device from the adapter body 1140. The ejection portion 1160 may include one or more openings 1162 in the top wall 1154 of the adapter body 1140. The openings 1162 may be configured to allow an ejection assembly of the applicator to pass through and contact the on-skin-wearable device and eject it from the adapter body 1140. The ejection assembly may include, for example, one or more protrusions configured to pass through the openings 1162.

[0245] One or more stabilizers 1170 (marked in FIG. 33C ) may be provided to stabilize the on-skin medical device within the holding area 1142. The stabilizers may include, for example, protrusions as shown in FIG. 33C . In embodiments, the stabilizers may have other forms. The stabilizers may be configured to contact the on-skin medical device to prevent the on-skin device from moving within the holding area 1142. For example, lateral movement may be resisted. The stabilizers 1170 may comprise one or more portions of the side wall 1144, including the inner surface 1146 of the side wall 1144.

[0246] 33A and 33B , the outer surface 1148 of the side wall 1144 may include a stabilizing feature 1164 that may be configured to stabilize the adapter body 1140 within the applicator. The stabilizing feature 1164 may comprise a recess in the outer surface 1148 of the side wall 1144. The stabilizing feature 1164 may have a contour and position similar to the stabilizing feature 523 shown in FIG. 27 , for example. Thus, the stabilizing feature 1164 may be utilized to stabilize the adapter body 1140 in a manner similar to the manner in which the stabilizing feature 523 stabilizes the on-skin sensor assembly 508 within the applicator. Other configurations of stabilizing features may be utilized as desired.

[0247] The adapter body 1140 may include a retainer portion 1166 for holding an on-skin medical device to the adapter body 1140. The retainer portion 1166 may have a variety of forms. In an example, the retainer portion 1166 may include one or more device couplers 1168 that may couple the on-skin medical device to the adapter body 1140.

[0248] 33C , the device coupler 1168 can include an adhesive that can couple the on-skin medical device to the adapter body 1140. The adhesive can include an adhesive layer that includes the inner surface 1156 of the top wall 1154. The adhesive can include a releasable coupler in the form of a releasable adhesive configured to release the on-skin medical device from the adapter body 1140.

[0249] 33A and 33B, an applicator coupler 1180 may be utilized to couple the adapter body 1140 to at least a portion of the applicator. The applicator coupler 1180 may include protrusions that may engage with the applicator. The applicator coupler 1180 may be configured similarly to the applicator coupler 1060 described with respect to FIGS. 29A and 29B.

[0250] 33A shows a top view of the adapter body 1140 positioned on the on-skin sensor assembly 1000. The spacing of the outer surface 1148 of the side wall 1144 from the outer surface 1008 of the wearable housing 1002 is visible.

[0251] Figure 33B shows a bottom view of the adapter body 1140 positioned on the on-skin sensor assembly 1000. Figure 33C shows a bottom view of the adapter body 1140 without the on-skin sensor assembly 1000 present.

[0252] FIG. 34A shows an adapter body 1140 coupled to an applicator. An engagement portion of the applicator, e.g., wearable retention elements 534a-d, may engage sidewall 1144 of adapter body 1140. The contact surface of sidewall 1144 may be located in the same position as coupling mechanism 521 shown in FIG. 27 engages with wearable retention elements 534a-d. The applicator includes a stabilizer 1070 that mates with stabilizing feature 1164 of adapter body 1140. Stabilizer 1070 may include, for example, a portion of needle carrier assembly 516 shown in FIG. 6.

[0253] 34A, the applicator coupler 1180 may not yet be coupled to the applicator because the deployment mechanism may be in a distal position prior to application to the host's skin. The deployment mechanism may be moved proximally upon contact with the host's skin during the deployment procedure.

[0254] FIG. 34B shows exemplary steps during deployment of the on-skin sensor assembly 1000 to the skin of a host. The applicator may be pressed against the surface of the skin, causing the deployment mechanism to retract proximally. The needle carrier assembly 516 may retract proximally relative to the holder 522, for example. Such movement may allow the applicator coupler 1180 to couple to the applicator. The applicator coupler 1180 may, for example, enter a recess or channel 1182 in the holder 522 to couple to the holder 522. FIG. 34C shows the configuration without the on-skin sensor assembly 1000 shown for clarity. The applicator coupler 1180 may hold the adapter body 1140 to the applicator after release of the on-skin wearable medical device from the adapter body 1140.

[0255] Once the on-skin sensor assembly 1000 is deployed on the host's skin, the holder 522 may be advanced distally according to methods disclosed herein. The applicator's ejection assembly may be activated, for example, when the holder 522 is advanced distally relative to the adapter body 1140.

[0256] For example, FIG. 34D shows an ejection assembly including an ejection actuator in the form of a protrusion 1190. The ejection actuator may be configured to eject the on-skin-wearable medical device from the adapter body 1140. The protrusion 1190 of the ejection actuator may extend through an opening in the adapter body 1140. The protrusion 1190 may advance distally to separate the on-skin sensor assembly 1000 from the device coupler 1168 by being pushed distally by the protrusion 1190. FIG. 34F shows a distal perspective view of the holder 522, for example, without the adapter body 1140 present. The protrusion 1190 extends distally from a surface of the holder 522.

[0257] The ejection assembly may be pushed distally with the needle carrier assembly 516 withdrawn, for example, as shown in FIG. 34E. The on-skin sensor assembly 1000 may be released from the adapter body 1140. The adapter body 1140 may be coupled to the applicator using an applicator coupler 1180 disposed in a recess or channel 1182 in the applicator.

[0258] In embodiments, other adapter body configurations may be utilized. Figure 35A shows an example of an adapter body 1200. Adapter body 1200 may include features of other adapter bodies disclosed herein unless otherwise stated.

[0259] 35A-35D, for example, the adapter body 1200 can include a holding area 1202 for receiving at least a portion of the on-skin medical device. The holding area 1202 can include, for example, a cavity for receiving at least a portion of the on-skin medical device.

[0260] The adapter body 1200 may include one or more walls that may define the boundaries of the holding area 1202. The one or more walls may include one or more side walls 1204 that may define the boundaries of the holding area 1202. The side walls 1204 may be configured to cover corresponding sides 1008 (marked in FIG. 28 ) of the on-skin sensor assembly 1000.

[0261] The upper wall 1204 may include an inner surface 1206 (marked in FIG. 35B ) and an outer surface 1208. The inner surface 1206 may be configured to face toward a portion of the on-skin medical device that may be placed within the retention area 1202. The outer surface 1208 may be configured to face opposite the inner surface 1206 and may face radially outward from the on-skin medical device.

[0262] The one or more side walls 1204 may have a spacing between the inner surface 1206 and the outer surface 1208, which may be configured to space the outer surface 1008 (marked in FIG. 28 ) of the on-skin medical device from the outer surface 1208 of the one or more side walls 1204. The thickness of the one or more side walls 1204 may form the spacing, or the spacing may be provided in other ways.

[0263] The inner surface 1206 may be configured to contact the outer surface 1008 of the on-skin medical device. The inner surface 1206 may be contoured to the shape of the outer surface 1008 of the on-skin medical device to provide a contour that matches the shape of the outer surface 1008. The outer surface 1208 of the adapter body 1200 may have a different contour than the inner surface 1206 of the adapter body 1200, in an example embodiment.

[0264] For example, the inner surface 1206 may form the inner periphery 1210 (marked in FIG. 35B ) of the adapter body 1200. The outer surface 1208 may form the outer periphery 1212 of the adapter body 1200. The inner periphery 1210 may have a different contour than the outer periphery 1212. Such a feature may allow for a difference in shape between the outer surface 1008 of the on-skin sensor assembly 1000 and the shape to which the adapter body 1200 conforms the on-skin sensor assembly 1000. The inner periphery 1210 may have a smaller diameter than the outer periphery 1212, in examples.

[0265] The spacing between the inner surface 1206 and the outer surface 1208 can accommodate an on-skin wearable medical device to fit into the engagement portion of the applicator. For example, the engagement portion of the applicator may be configured to engage an on-skin sensor assembly having a larger diameter than the on-skin sensor assembly 1000. The spacing can compensate for the difference in diameter. Alternatively, or in combination, the spacing can compensate for the difference in shape between the on-skin sensor assemblies.

[0266] The outer surface 1208 of the side wall 1204 may include a stabilizing feature 1240 that may be configured to stabilize the adapter body 1200 within an applicator. The stabilizing feature 1240 may comprise a recess in the outer surface 1208 of the side wall 1204. The stabilizing feature 1240 may have a contour and position similar to the stabilizing feature 523 shown in FIG. 27 , for example. Thus, the stabilizing feature 1240 may be utilized to stabilize the adapter body 1200 in a manner similar to the manner in which the stabilizing feature 523 stabilizes the on-skin sensor assembly 508 within an applicator. Other configurations of stabilizing features may be utilized as desired.

[0267] The one or more walls may include an upper wall 1214 (marked in FIG. 35A ) that may define the boundary of the retention area 1202. The upper wall 1214 may be configured to cover a corresponding outer top, upper, or proximal surface 1010 (marked in FIG. 28 ) of the on-skin medical device. The upper wall 1214 may include an inner surface 1216 (marked in FIG. 35B ) and an outer surface 1218. The inner surface 1216 may be configured to face toward a portion of the on-skin medical device that may be positioned within the retention area 1202. The outer surface 1218 may be configured to face opposite the inner surface 1216 and may face radially outward from the on-skin medical device.

[0268] The top wall 1214 may have a spacing between the inner surface 1216 and the outer surface 1218 that may be configured to space the outer top, upper, or proximal surface 1010 (shown in FIG. 28 ) of the on-skin medical device from the outer surface 1218 of the top wall 1214. The outer surface 1010 of the on-skin medical device may comprise, for example, the outer top surface 1010 of the housing 1002. The thickness of the top wall 1214 may form the spacing, or the spacing may be provided in other ways. The top wall 1214 may include an opening 1215 that may allow for the insertion or retraction of an insertion element, such as a needle.

[0269] The inner surface 1216 may be configured to contact the outer surface 1010 of the on-skin medical device. The inner surface 1216 may be contoured to the shape of the outer surface 1010 of the on-skin medical device to provide a contour that matches the shape of the outer surface 1010. The outer top surface 1218 of the adapter body 1200, in examples, may have a different contour than the inner surface 1216 of the adapter body 1200.

[0270] The spacing between the inner surface 1216 and the outer surface 1218 can accommodate an on-skin wearable medical device to fit into the engagement portion of the applicator. For example, the engagement portion of the applicator may be configured to engage an on-skin sensor assembly having a greater height than the on-skin sensor assembly 1000. The spacing can compensate for the height difference. Alternatively, or in combination, the spacing can compensate for the shape difference between the on-skin sensor assemblies.

[0271] In some embodiments, side wall 1204 can extend distally from top wall 1214. In some embodiments, side wall 1204 can extend distally from an outer edge or perimeter of top wall 1214. Other configurations can be provided in some embodiments.

[0272] The adapter body 1200 may include a retainer portion 1220 for holding an on-skin medical device to the adapter body 1200. The retainer portion 1220 may have a variety of forms. In an example, the retainer portion 1220 may include one or more device couplers 1222 that may couple the on-skin medical device to the adapter body 1080.

[0273] The device coupler 1222 may have various forms in embodiments. With reference to FIG. 35B , the device coupler 1222 may include a protrusion 1224 that may be configured to engage with the on-skin sensor assembly 1000. The protrusion 1224 may be configured to engage a mating feature on the wearable housing 1002 of the on-skin sensor assembly 1000, which may have a different configuration than the mating feature shown in FIG. 28 , for example. The mating feature may be located, for example, at an end portion of the wearable housing 1002. Other locations may be utilized as desired. The protrusion 1224 may enter a mating feature in the form of a recess in the wearable housing 1002. The device coupler 1222 may have other forms in embodiments. For example, the device coupler may include a protrusion or a recess, or one or more of a protrusion or a recess. The device coupler may include an adhesive or have another form.

[0274] The device coupler 1222 may include arms in some embodiments. For example, the arms 1226 may extend circumferentially around the outer periphery of the adapter body 1200. The arms 1226 may extend circumferentially from the hinge portion 1228 to respective ends 1230 of the arms 1226. Each arm 1226 may extend circumferentially along a side of the wearable housing 1002. Each arm 1226 may include a protrusion 1224.

[0275] Each hinge portion 1228 may allow each arm 1226 to flex radially outward from the wearable housing 1002. The hinge portions 1228 may be configured to pivot about an axis that extends transversely or perpendicular to the plane of the adapter body 1200 (e.g., the plane of the top wall 1214).

[0276] Arms 1226, in examples, can define the boundaries of retention area 1202. Arms 1226 can flex radially outward from retention area 1202 to allow release of the on-skin medical device from retention area 1202 of adapter body 1200.

[0277] Arms 1226 of device coupler 1222 may comprise a majority of circumference 1212 of adapter body 1200. Arms 1226 may comprise at least 60%, 70%, or 80% of circumference 1212, in embodiments.

[0278] The device coupler 1222 may include a releasable coupler configured to release the on-skin wearable medical device from the adapter body 1200. The device coupler 1222 may be configured to deflect, for example, to release the on-skin wearable medical device from the adapter body 1200. The deflection may be in a radially outward direction to allow the device coupler 1222 to separate from the on-skin wearable medical device.

[0279] In an embodiment, the adapter body 1200 may include one or more supports 1232. The supports 1232 may be configured to support the device coupler 1222 in a coupled configuration with the on-skin medical device. The supports 1232 may have various forms and may comprise a contact surface of the adapter body 1200. The supports 1232 may include hooks, as shown in FIG. 35B . The hooks may extend around the applicator contact surface 1234 (marked in FIG. 35G ) and be configured to press the device coupler 1222 toward the on-skin medical device. The applicator contact surface 1234 may include at least one post that can engage with the hooks. Thus, the device coupler 1222 may be held in a coupled configuration with the on-skin medical device. The posts may be configured to be withdrawn from the hooks, allowing the device coupler 1222 to be separated from a portion of the on-skin medical device. The post may be withdrawn during retraction of the insertion element or needle to guide the transcutaneous analyte sensor into the host's skin, as disclosed herein. Support 1232 may have other configurations in embodiments.

[0280] In an embodiment, the device coupler 1222 may be biased to extend radially outward from the retention area 1202. Thus, upon release of the support portion 1232, the device coupler 1222 may be released from the on-skin medical device.

[0281] Figure 35C shows a top view of the adapter body 1200 placed on the on-skin medical device. Figure 35D shows a bottom view of the adapter body 1200 placed on the on-skin medical device.

[0282] FIG. 35E shows the adapter body 1200 coupled to an applicator. An engagement portion of the applicator, e.g., wearable retention elements 534a-d, can engage the sidewall 1204 of the adapter body 1200. The contact surface of the sidewall 1204 can be located in the same position as the coupling feature 521 shown in FIG. 27 where it engages with the wearable retention elements 534a-d. The applicator includes at least one stabilizer 1235 having a contact surface 1234 that mates with the support portion 1232 of the adapter body 1200. The stabilizer 1235 can include a post that engages with a hook on the support portion 1232. The hook can wrap around the post. The contact between the stabilizer 1235 and the support portion 1232 of the adapter body 1200 is shown in a perspective view in FIG. 35G. The contact can hold the device coupler 1222 in a closed configuration.

[0283] 35F shows the assembly prior to retraction of the needle carrier assembly 516. The needle carrier assembly 516 may be retracted in a deployment procedure according to methods disclosed herein. Accordingly, the engagement portion of the applicator in the form of the wearable retention elements 534a-d may be released from the adapter body 1200 in a manner similar to that disclosed herein with respect to the on-skin sensor assembly 508 (e.g., FIGS. 15 and 16 show exemplary releases).

[0284] The stabilizer 1235, which has a contact surface for contacting the support portion 1232 of the adapter body 1200, may be retracted. The post may be retracted from a position between the hooks of the support portion 1232. Thus, the post may no longer be between the hooks of the support portion 1232. Thus, the support portion 1232 may not be supported by a contact surface, and the device coupler 1222 may be configured to deflect radially outward. The hooks may release in opposite directions, causing the device coupler 1222 to deflect radially outward and separate from the on-skin-wearable medical device. The outward deflection of the device coupler 1222 may allow the on-skin sensor assembly 1000 to be released from the adapter body 1200. The on-skin sensor assembly 1000 may be deployed on the host's skin using an adhesive or other form of engagement with the skin, and thus may remain deployed on the skin upon removal of the applicator from the skin.

[0285] In embodiments, other configurations of the adapter body may be utilized. Figure 36A shows an example of an adapter body 1250. The adapter body 1250 may include features of other examples of the adapter body unless otherwise stated.

[0286] 36A, the adapter body 1250 can include a holding area 1252 for receiving at least a portion of the on-skin medical device. The holding area 1252 can comprise, for example, a cavity for receiving at least a portion of the on-skin medical device.

[0287] The adapter body 1250 may include one or more walls that may define a boundary of the holding area 1252. The one or more walls may include one or more side walls 1254 that may define a boundary of the holding area 1252. The side walls 1254 may be configured to cover corresponding sides 1008 (marked in FIG. 28 ) of the on-skin sensor assembly 1000.

[0288] Side wall 1254 can include an inner surface 1256 and an outer surface 1258. Inner surface 1256 can be configured to face toward a portion of a on-skin medical device that can be placed within retention area 1252. Outer surface 1258 can be configured to face the opposite side from inner surface 1256 and can face radially outward from the on-skin medical device.

[0289] The one or more side walls 1254 may have a spacing between the inner surface 1256 and the outer surface 1258, which may be configured to space an outer surface 1260 (marked in FIG. 36B ) of the on-skin medical device from the outer surface 1258 of the one or more side walls 1254. The outer surface 1260 of the on-skin medical device may include, for example, the outer surface 1260 of a housing 1272 of the on-skin medical device. The thickness of the one or more side walls 1254 may form the spacing, or the spacing may be provided in other ways.

[0290] The inner surface 1256 may be configured to contact the outer surface 1260 of the on-skin medical device. The inner surface 1256 may be contoured to the shape of the outer surface 1260 of the on-skin medical device to provide a contour that matches the shape of the outer surface 1260. The outer surface 1258 of the adapter body 1250 may have a different contour than the inner surface 1256 of the adapter body 1250, in some embodiments.

[0291] For example, the inner surface 1256 may form the inner periphery 1262 of the adapter body 1250. The outer surface 1258 may form the outer periphery 1264 of the adapter body 1250. The inner periphery 1262 may have a different contour than the outer periphery 1264. Such a feature may allow for a difference in shape between the outer surface 1260 of the on-skin sensor assembly 1259 and the shape to which the adapter body 1250 conforms the on-skin sensor assembly 1259.

[0292] The spacing between the inner surface 1256 and the outer surface 1258 can accommodate an on-skin wearable medical device to fit into the engagement portion of the applicator. For example, the engagement portion of the applicator may be configured to engage an on-skin sensor assembly having a larger diameter than the on-skin sensor assembly 1259. The spacing can compensate for the difference in diameter. Alternatively, or in combination, the spacing can compensate for the difference in shape between the on-skin sensor assemblies.

[0293] The adapter body 1250 may include a ring that extends around the retention area 1252 .

[0294] The adapter body 1250 may include a retainer portion 1266 for holding an on-skin medical device to the adapter body 1250. The retainer portion 1266 may have a variety of forms. In an example, the retainer portion 1266 may include one or more device couplers 1268 that may couple the on-skin medical device to the adapter body 1250.

[0295] The device coupler 1268 may have various forms in embodiments. With reference to FIG. 36A , the device coupler 1268 may include a protrusion that may be configured to engage with the on-skin sensor assembly 1259. The protrusion may be configured to engage a mating feature 1270 (marked in FIG. 36B ) on the wearable housing 1272 of the on-skin sensor assembly 1259. The protrusion may enter the mating feature 1270 in the form of a recess in the wearable housing 1272. The device coupler 1268 may have other forms in embodiments. For example, the device coupler may include a protrusion or a recess, or one or more of a protrusion or a recess. The device coupler may include an adhesive or may have another form. A ball and groove arrangement (e.g., having a mating feature 1270 that includes a groove) may be utilized.

[0296] Device coupler 1268 may be disposed on inner surface 1256 of sidewall 1254 and may be configured to extend radially inward toward retention area 1252. Device coupler 1268 may have other locations in embodiments.

[0297] The device coupler 1268 may include a releasable coupler configured to release the on-skin wearable medical device from the adapter body 1250. The device coupler 1268 may be configured to release from the on-skin wearable medical device when a sufficient force is applied to the device coupler 1268. The protrusions may disengage from the coupling features 1270. In examples in which the device coupler 1268 includes recesses, the protrusions of the wearable housing 1272 may disengage from the recesses of the adapter body 1250 to provide for release of the adapter body 1250.

[0298] An applicator coupler 1274 may be utilized to couple the adapter body 1250 to at least a portion of the applicator. The applicator coupler 1274 may include a recess that may engage a protrusion on the applicator. The applicator coupler 1274 may have other configurations, such as a protrusion or adhesive. In embodiments, one or more protrusions or recesses may be provided. As shown in FIG. 36A , the applicator coupler 1274 may be disposed on the outer surface 1258 of the sidewall 1254, or in another location as desired.

[0299] 36B shows a perspective view of an exemplary on-skin sensor assembly 1259 that may be utilized with the adapter body 1250. The adapter body 1250 may enclose the wearable housing 1272 of the on-skin sensor assembly 1259.

[0300] Figure 36C, for example, shows adapter body 1250 disposed about wearable housing 1272. Device coupler 1268 can mate with coupling feature 1270. Figure 37, for example, shows a cross-sectional view along line CC' of Figure 36C.

[0301] The applicator engagement portion can be configured to engage the adapter body 1250. The engagement portion can include a wearable retention and / or alignment element as disclosed herein, or can have other configurations. FIG. 38 shows an engagement portion 1280 configuration that includes a retention element in the form of a protrusion 1282, for example. The protrusion 1282 can be located on an arm of the wearable retention and / or alignment element as disclosed herein, or can have other configurations. Other configurations (e.g., recesses, adhesive) can be utilized as desired. The wearable retention and / or alignment element can comprise part of a needle carrier assembly as disclosed herein. The engagement portion 1280 can be configured to engage the applicator coupler 1274, as shown in the cross-sectional view of FIG. 39A. The protrusion 1282 can engage the applicator coupler 1274, or another coupling configuration can occur.

[0302] The adapter body 1250 may be adapted to mate the on-skin sensor assembly 1259 with the engagement portion 1280 .

[0303] The engagement portion 1280 can be configured to release from the adapter body 1250, in embodiments. For example, with reference to FIG. 39B , the engagement portion 1280 of the applicator can be released when pulled from the adapter body 1250. The protrusion 1282 can be separated from the applicator coupler 1274 when a force is applied that pulls the protrusion 1282 from the applicator coupler 1274. The engagement portion 1280 can, for example, deflect from the applicator coupler 1274 to release. The arms of the wearable retention and / or alignment element can, for example, deflect outward to release the protrusion 1282 from the applicator coupler 1274. Other release configurations can be utilized as needed. In embodiments, the adapter body 1250 can be detached from the wearable housing 1272 if desired. The on-skin-wearable medical device can be released from the adapter body 1250. FIG. 39C , for example, illustrates the resulting configuration. The device coupler 1268 may be separated from the coupling feature 1270 .

[0304] In embodiments, the adapter body 1250 may remain engaged with the engagement portion 1280 upon deployment of the wearable housing 1272. For example, the wearable housing 1272 may be separated from the adapter body 1250 and remain on the host's skin. The adapter body 1250 may remain engaged with the engagement portion 1280 and may be retracted from the host's skin along with the applicator's engagement portion 1280. The wearable housing 1272 may remain disposed on the host's skin, for example, as depicted in FIG. 39C.

[0305] In some embodiments, the adapter body 1250 may interface between the on-skin-wearable medical device and the applicator such that the applicator cannot engage with other configurations of the on-skin-wearable medical device. For example, in configurations such as those shown in FIGS. 36A-39C , the engagement portion 1280 may not be able to engage with other configurations of the on-skin-wearable medical device. The adapter body 1250 may further interface with the engagement portion 1280 by mating the on-skin-wearable medical device with the engagement portion 1280. Such a configuration may be useful for mating on-skin-wearable medical devices of multiple different sizes or other configurations with a single configuration of the engagement portion. For example, with reference to FIGS. 36A-39C , multiple different adapter bodies may be utilized to mating on-skin-wearable medical devices of multiple different configurations with the engagement portion 1280. Adapter bodies of different diameters or shapes may be utilized to accommodate multiple adapter bodies of different diameters or shapes having the same engagement portion 1280. Other configurations of the engagement portion and on-skin-wearable medical device may be accounted for through the use of adapter bodies.

[0306] Applicators disclosed herein (e.g., applicators disclosed herein including applicators 500, 700, 900) may include an actuation body 1300 (e.g., marked in FIG. 30B ) that can be utilized to electrically activate an on-skin wearable medical device or on-skin sensor assembly 1000. Features and operation of the actuation body 1300 are disclosed in U.S. patent application Ser. No. 16 / 400,974, filed May 1, 2019, and published November 7, 2019 as U.S. Patent Application Publication No. 2019-0160974, the entire contents of which are incorporated by reference for all purposes. The actuation body 1300 may operate to activate the sensor electronics module 140 of the on-skin sensor assembly 1000 through remote sensing by the sensor electronics module 140. The sensor electronics module 140 may include, for example, a proximity sensor that can detect the proximity of the actuation body 1300. The proximity sensor may have the form disclosed in U.S. Patent Application Publication No. 2007 / 0129999, such as a Hall Effect sensor, a reed switch, or other form of proximity sensor. The proximity sensor may be a magnetic field sensor for sensing the magnetic field of the actuation body 1300. The actuation body 1300 may include, for example, a magnet that generates a magnetic field. Variations in the proximity of the proximity sensor to the actuation body 1300 (e.g., variations in the strength of the magnetic field generated by the actuation body 1300 due to distance) may be sensed and utilized to activate the on-skin sensor assembly 1000.

[0307] Electrical activation may occur from a lower power state to a higher power state in the manner disclosed in U.S. Patent Application Publication No. 2007 / 0129990. The on-skin sensor assembly 1000 and sensor electronics module 140 may be held in a low-power or quiescent state when coupled to an applicator (e.g., an applicator disclosed herein, including applicators 500, 700, and 900), since the on-skin sensor assembly 1000 is not being used in such a configuration. The on-skin sensor assembly 1000 may conserve battery power in such a configuration. Upon deployment, the on-skin sensor assembly 1000 is intended for use and thus can be activated to a higher power state for operation of the on-skin sensor assembly 1000 on the host's skin. The distance between the on-skin sensor assembly 1000 and the actuating body 1300 increases upon application of the on-skin sensor assembly 1000 when the applicator is removed from the on-skin sensor assembly 1000 positioned on the host's skin. The increase in distance is detected by the proximity sensor, and therefore the on-skin sensor assembly 1000 is activated into a higher power state for use.

[0308] 30B , the position of the actuating body 1300 on the applicator may require a large actuating body 1300 (e.g., a large magnet) to generate a magnetic field sufficient to be sensed by the sensor electronics module 140 of the on-skin sensor assembly 1000. Furthermore, if the size of the on-skin sensor assembly 1000 is reduced, or if the presence of additional structure, such as an adapter or other configuration change, increases the distance between the actuating body 1300 of the applicator and the sensor electronics module 140, an even larger actuating body 1300 (e.g., a larger magnet) may be required due to the increased distance between the actuating body 1300 and the on-skin sensor assembly 1000.

[0309] 40 shows an example where adapter body 1302 includes actuation body 1304. Actuation body 1304 operates similarly to actuation body 1300. Actuation body 1304 can include a magnet.

[0310] The adapter body 1302 is configured similarly to other examples of the adapter body disclosed herein. The adapter body 1302 includes one or more walls 1306, 1308 that define a holding area 1310 for receiving the on-skin sensor assembly 1000. The one or more walls include one or more side walls 1306 and a top wall 1308. The adapter body 1302 may include one or more device couplers 1312 that may couple the on-skin sensor assembly 1000 to the adapter body 1302. The device couplers 1312 may include arms that extend along the sides of the on-skin sensor assembly 1000 and may operate in a manner similar to, for example, the device coupler 1106 of FIGS. 31A-31C. Other configurations of device couplers as disclosed herein may also be utilized.

[0311] The actuation body 1304 may be disposed in or on one or more walls 1306, 1308. The actuation body 1304 in FIG. 40 is disposed on the top wall 1308. The actuation body 1304 may be disposed on the receiver 1314 on the outer surface 1316 of the top wall 1308, or on another surface (e.g., the inner surface 1318 marked in FIG. 41 ). The receiver 1314 may include a cavity or have another configuration. In an embodiment, the actuation body 1304 may be disposed on the side wall 1306. In an embodiment, the receiver 1314 or other portion of the adapter body 1302 may include one or more securing features (e.g., a snap-fit ​​mechanism, a retention tab, or an adhesive) to retain the actuation body 1304 within the receiver.

[0312] The actuating body 1304 may be positioned proximate to the proximity sensor of the on-skin sensor assembly 1000 when the assembly 1000 is received within the adapter body 1302. FIG. 41 shows a cross-sectional view of FIG. 40 along line D-D′, showing the actuating body 1304 positioned above and proximate to the sensor electronics 140 of the on-skin sensor assembly 1000, which may include, for example, the proximity sensor. The location of the actuating body 1304 on the adapter body 1302 may advantageously increase the proximity of the actuating body 1304 to the proximity sensor of the on-skin sensor assembly 1000. A larger magnetic field may be provided for detection by the proximity sensor. A smaller actuating body 1304 than the actuating body 1300 may be utilized to provide a field or other signal for detection by the proximity sensor.

[0313] Any of the adapter bodies disclosed herein may incorporate an actuation body 1304 as disclosed herein. The actuation body 1304 may include a magnet or may have other forms depending on the form of the proximity sensor utilized (e.g., in examples where the proximity sensor includes a magnet, a magnetically responsive material may be utilized; an electric field generator (e.g., a charged body) may be utilized; an optical indicator may be utilized for optical sensing, among other things).

[0314] Upon activation, the actuating body 1304 may operate similarly to the actuating body 1300. The distance between the actuating body 1304 and the on-skin sensor assembly 1000 increases upon deployment of the on-skin sensor assembly 1000 to the host's skin. The proximity sensor senses the removal of the actuating body 1304 and electrically activates the on-skin sensor assembly 1000 from a low power state to a high power state. Variations in the actuation method may be provided in the embodiments.

[0315] Features of the adapter body may enable interfacing of different configurations of on-skin medical devices with applicators of various configurations. In an example, the applicator may include a universal applicator, and the adapter body interfaces to enable the on-skin medical device to engage the universal applicator.

[0316] Features of the embodiments disclosed herein may be used alone or in combination with any other system, device, or method disclosed herein.

[0317] The foregoing description presents the best modes contemplated for carrying out this invention, manners and processes for making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains to make and use the invention. The invention is, however, susceptible to modifications and alternative constructions from those contemplated above that are of full equivalents. Consequently, the invention is not limited to the particular embodiments disclosed. On the contrary, the invention covers all modifications and alternative constructions that are within the spirit and scope of the invention as generally expressed by the following claims, which particularly point out and separately claim the subject matter of the invention. While the present disclosure has been illustrated and described in detail in the drawings and foregoing specification, such illustration and description is to be considered illustrative or exemplary and not restrictive.

[0318] All references cited herein are incorporated by reference in their entirety. To the extent that publications and patents or patent applications incorporated by reference conflict with the present disclosure contained herein, the present specification is intended to supersede and / or supersede any such conflicting material.

[0319] Unless otherwise defined, all terms (including technical and scientific terms) are to be given their ordinary and customary meanings to those of ordinary skill in the art and should not be limited to any special or customized meaning unless expressly defined as such herein. It should be noted that the use of a particular term when describing a particular feature or aspect of the present disclosure should not be construed as implying that the term is being redefined herein to be limited to include any specific characteristics of the feature or aspect of the present disclosure with which the term is associated. Terms and phrases used in this application, and variations thereof, unless expressly stated otherwise, particularly in the appended claims, should be construed as open-ended, as opposed to limiting. For example, the term "comprising" should be read to mean "including without limitation," "including, but not limited to," etc. The term "comprising," as used herein, is synonymous with "including," "containing," or "characterized by," and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. The term "having" should be interpreted as "having at least." The term "including" should be interpreted as "including but not limited to."The term "example" is used to provide illustrative instances of the item under discussion, and not an exhaustive or limiting list thereof; adjectives such as "known," "normal," "standard," and similar terms should not be construed as limiting the described items to a given period of time or to items available at a given time, but rather should be read to encompass known, conventional, or standard technology that may be available or known at any time now or in the future; and words such as "preferably," "preferred," "desired," or "desirable," and similar terms should not be understood to imply that a particular feature is critical, essential, or even essential to the structure or function of the invention, but rather are merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment. Similarly, a group of items joined by the conjunction "and" should not be read as requiring any and all of those items to be present in the group, but rather should be read as "and / or" unless expressly stated otherwise. Similarly, a group of items joined by the conjunction "or" should not be read as requiring mutual exclusivity among the group, but rather should be read as "and / or" unless expressly stated otherwise.

[0320] When a range of values ​​is provided, it is understood that the upper and lower limits, and each intervening value between the upper and lower limits of the range, are included within the examples.

[0321] With respect to the use of virtually any plural and / or singular term in this specification, those skilled in the art can interpret the plural into the singular and / or the singular into the plural as appropriate to the context and / or application. For clarity, various singular / plural permutations may be explicitly set forth herein. The indefinite articles "a" or "an" do not exclude plurals. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain means are recited in mutually different dependent claims does not indicate that a combination of these means cannot be used to advantage. Reference signs in the claims shall not be construed as limiting the scope.

[0322] Those skilled in the art will further understand that where a specific number is intended in an introduced claim recitation, such intention will be expressly recited in the claim, and that the absence of such recitation indicates no such intention. For example, to aid in understanding, the following appended claims may include the use of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed as suggesting that introducing a claim recitation with the indefinite article "a" or "an" limits any particular claim including such an introduced claim recitation to embodiments containing only one such recitation, even when the introductory phrases "one or more" or "at least one" and indefinite articles, such as "a" or "an," are included in the same claim (e.g., "a" and / or "an" should generally be construed to mean "at least one" or "one or more"). The same applies to the use of definite articles used to introduce claim recitations. Additionally, even when a specific number of enumerations in an introduced claim is explicitly recited, those skilled in the art will recognize that such enumeration should typically be interpreted to mean at least the recited number (e.g., the mere recitation of "two enumerations" without other modifiers typically means at least two enumerations, or more than two enumerations). Furthermore, when a conventional expression similar to "at least one of A, B, and C, etc." is used, such a structure is generally intended in the sense that a skilled artisan would understand the conventional expression (e.g., "a system having at least one of A, B, and C" includes, but is not limited to, systems having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, and C, etc.).When conventional language similar to "at least one of A, B, or C, etc." is used, such a structure is generally intended in the sense that one of ordinary skill in the art would understand the conventional language (e.g., "a system having at least one of A, B, or C" includes, but is not limited to, a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, and C, etc.). One of ordinary skill in the art will further understand that virtually any disjunctive word and / or phrase presenting two or more alternative terms, whether in the specification, claims, or drawings, should be understood to contemplate the possibility of including one of those terms, either of those terms, or both terms. For example, the phrase "A or B" is understood to include the possibilities of "A" or "B" or "A and B."

[0323] All numerical values ​​expressing quantities of raw materials, reaction conditions, and the like used herein should be understood to be modified in all instances by the term "about." Accordingly, unless otherwise indicated, the numerical parameters set forth herein are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of any claims in any application claiming priority to this application, each numerical parameter should be construed in light of the number of significant digits and ordinary rounding approaches.

[0324] Moreover, while the foregoing has been described in some detail by way of illustration and example for purposes of clarity and understanding, it will be apparent to those skilled in the art that certain changes and modifications may be practiced. Therefore, the descriptions and examples should not be construed as limiting the scope of the invention to the specific examples described herein, but on the contrary, they should be construed as covering all modifications and alternatives that come within the true scope and spirit of the invention.

Claims

1. 1. An apparatus comprising: An apparatus comprising: an adapter body configured to interface between at least a portion of an on-skin medical device and an applicator of the on-skin medical device.

2. 10. The device of claim 1, wherein the adapter body is configured to interface between at least the portion of the on-skin medical device having a first configuration and a portion of the applicator configured to engage a second configuration of at least the portion of the on-skin medical device that is different from the first configuration.

3. The apparatus of claim 2 , wherein the second configuration differs from the first configuration in one or more of shape or size.

4. the on-skin medical device having at least the portion having the first configuration is a first on-skin medical device, and the on-skin medical device having at least the portion having the second configuration is a second on-skin medical device; the first configuration includes a configuration of a first wearable housing of the first on-skin medical device; The apparatus of claim 2 or 3, wherein the second configuration comprises a configuration of a second wearable housing of the second on-skin medical device.

5. The apparatus of claim 2 or 3, wherein the on-skin medical device having at least the portion having the first configuration is the same as the on-skin medical device having at least the portion having the second configuration.

6. the on-skin medical device is a first on-skin medical device; The apparatus of any one of claims 1 to 5, wherein the adapter body is configured to interface with a wearable housing of the first on-skin wearable medical device that is smaller than a wearable housing of a second on-skin wearable medical device with which the applicator is configured to engage.

7. 7. The apparatus of claim 6, wherein the wearable housing of the first on-skin medical device has a smaller diameter or height than the wearable housing of the second on-skin medical device.

8. The apparatus of any one of claims 1 to 7, wherein the adapter body is configured to adapt at least the portion of the on-skin medical device to fit into an engagement portion of the applicator.

9. The apparatus of any one of claims 1 to 8, wherein the adapter body includes a holding area for receiving at least the portion of the on-skin medical device.

10. The apparatus of any one of claims 1 to 9, wherein the adapter body includes a cavity for receiving at least the portion of the on-skin medical device.

11. The apparatus of any one of claims 1 to 10, wherein the adapter body includes one or more walls that define a holding area for receiving at least the portion of the on-skin medical device.

12. The device of claim 11 , wherein the one or more walls include one or more side walls that define the boundaries of the holding area.

13. 13. The device of claim 12, wherein the one or more side walls include an inner surface and an outer surface, the inner surface configured to face the portion of the on-skin medical device, and the outer surface configured to face the opposite side from the inner surface.

14. 14. The device of claim 13, wherein the one or more side walls have a spacing between the inner surface and the outer surface configured to space the outer surface of the on-skin medical device from the outer surface of the one or more side walls.

15. The apparatus of claim 14 , wherein the spacing is configured to accommodate at least the portion of the on-skin medical device to fit into an engagement portion of the applicator.

16. 16. The apparatus of any one of claims 13 to 15, wherein the inner surface of the one or more side walls defines an inner periphery having a contour different from an outer periphery defined by the outer surface of the one or more side walls.

17. 17. The apparatus of any one of claims 13 to 16, wherein the inner surface of the one or more side walls defines an inner circumference having a smaller diameter than an outer circumference defined by the outer surface of the one or more side walls.

18. The device of any one of claims 11 to 17, wherein the one or more walls include a top wall that defines the boundary of the holding area.

19. 20. The apparatus of claim 18, wherein the upper wall includes an inner surface and an outer surface, the inner surface configured to face the portion of the on-skin medical device, and the outer surface configured to face the opposite side from the inner surface.

20. 20. The apparatus of claim 19, wherein the top wall has a spacing between the inner and outer surfaces configured to space an outer surface of the on-skin medical device from the outer surface of the top wall.

21. 21. The apparatus of claim 20, wherein the spacing is configured to accommodate at least the portion of the on-skin medical device to fit into an engagement portion of the applicator.

22. The system of any one of claims 9 to 21, further comprising one or more stabilizers for stabilizing at least a portion of the on-skin medical device within the holding area.

23. 23. The apparatus of claim 22, wherein the one or more stabilizers include one or more protrusions for contacting at least the portion of the on-skin medical device.

24. The apparatus of any one of claims 1 to 23, wherein the adapter body comprises a ring extending around a holding area for receiving at least the portion of the on-skin medical device.

25. The apparatus of any one of claims 1 to 24, wherein the adapter body includes a holding portion for holding at least the portion of the on-skin medical device to the adapter body.

26. The apparatus of any one of claims 1 to 25, further comprising one or more device couplers for coupling the on-skin medical device to the adapter body.

27. 27. The apparatus of claim 26, wherein the one or more device couplers comprise an adhesive.

28. 28. The apparatus of claim 26 or 27, wherein the one or more device couplers include one or more of a protrusion or a recess configured to engage at least the portion of the on-skin medical device.

29. 29. The apparatus of any one of claims 26 to 28, wherein the one or more device couplers are configured to flex.

30. 30. The apparatus of any one of claims 26 to 29, wherein the one or more device couplers include a releasable coupler configured to release the on-skin medical device from the adapter body.

31. The apparatus of any one of claims 26 to 30, wherein the one or more device couplers include one or more arms.

32. 32. The apparatus of claim 31, wherein the one or more arms define a holding area for receiving at least the portion of the on-skin medical device.

33. 33. The apparatus of claim 31 or 32, wherein the one or more arms are configured to deflect radially outward from a holding area for receiving at least the portion of the on-skin medical device.

34. The apparatus of any one of claims 26 to 33, wherein the adapter body includes one or more supports configured to support the one or more device couplers in a coupled configuration with at least the portion of the on-skin medical device.

35. 35. The device of claim 34, wherein the one or more support portions include one or more contact surfaces of the adapter body.

36. 36. The device of claim 34 or 35, wherein the one or more supports include one or more hooks.

37. 37. The apparatus of any one of claims 1 to 36, further comprising one or more applicator couplers for coupling the adapter body to at least a portion of the applicator.

38. 38. The device of claim 37, wherein the one or more applicator couplers include one or more protrusions or recesses configured to engage at least the portion of the applicator.

39. The apparatus of any one of claims 1 to 38, wherein the adapter body includes an ejection portion configured to eject at least the portion of the on-skin medical device from the adapter body.

40. 40. The apparatus of claim 39, wherein the vent comprises one or more openings in a surface of the adapter body.

41. The apparatus of any one of claims 1 to 40, wherein the on-skin medical device includes a transcutaneous analyte sensor, and the adapter body is configured to be disposed within a housing of the applicator.

42. 42. The apparatus of any one of claims 1 to 41, wherein the adapter body includes an actuation body configured to electrically actuate the on-skin medical device.

43. 43. The device of claim 42, wherein the actuating body includes a magnet.

44. 44. The apparatus of claim 42 or 43, wherein the adapter body includes one or more walls that define a holding area for receiving at least the portion of the on-skin medical device, and the actuation body is disposed on at least one of the one or more walls.

45. 45. The device of claim 44, wherein the one or more walls include a top wall that defines the holding area, and the actuation body is disposed on the top wall.

46. 1. A system comprising: an applicator for an epicutaneous medical device; A system comprising an adapter body configured to interface between at least a portion of the on-skin medical device and the applicator of the on-skin medical device.

47. 47. The system of claim 46, wherein the applicator includes an engagement portion configured to engage the adapter body.

48. 48. The system of claim 47, wherein the engagement portion is configured to engage an outer surface of the adapter body.

49. 49. The system of claim 47 or 48, wherein the on-skin medical device is a first on-skin medical device, and the engagement portion is configured to engage a second on-skin medical device having a different configuration than the first on-skin medical device.

50. 50. The system of claim 49, wherein the first on-skin medical device has a wearable housing having a smaller diameter or height than the wearable housing of the second on-skin medical device.

51. The system of any one of claims 47 to 50, wherein the on-skin medical device is a first on-skin medical device having a first wearable housing, the engagement portion being sized to fit into a second wearable housing of a second on-skin medical device, the second wearable housing having a larger diameter or height than the first wearable housing.

52. The system of any one of claims 47 to 51, wherein the adapter body is configured to adapt at least the portion of the on-skin medical device to fit into an engagement portion of the applicator.

53. The system of any one of claims 46 to 52, wherein the adapter body includes a holding area for receiving at least the portion of the on-skin medical device.

54. The system of any one of claims 46 to 53, wherein the adapter body includes a cavity for receiving at least the portion of the on-skin medical device.

55. The system of any one of claims 46 to 54, wherein the adapter body includes one or more walls that define a holding area for receiving at least the portion of the on-skin medical device.

56. 56. The system of claim 55, wherein the applicator includes an engagement portion configured to engage at least a portion of the one or more walls.

57. The system of any one of claims 46 to 56, wherein the adapter body includes one or more device couplers for coupling the on-skin medical device to the adapter body.

58. 58. The system of claim 57, wherein the one or more device couplers include a releasable coupler configured to release the on-skin medical device from the adapter body.

59. the adapter body includes one or more supports configured to support the one or more device couplers in a coupled configuration with at least the portion of the on-skin medical device; 59. The system of claim 57 or 58, wherein the applicator includes one or more contact surfaces configured to abut the one or more supports.

60. 60. The system of claim 59, wherein the one or more supports include one or more hooks.

61. 61. The system of claim 60, wherein the one or more contact surfaces include at least one post configured to engage with the one or more hooks, the at least one post configured to withdraw from the one or more hooks to separate the one or more device couplers from at least the portion of the on-skin medical device.

62. 62. The system of claim 61, wherein the applicator is configured such that the at least one post is withdrawn during retraction of a needle to guide the transcutaneous analyte sensor into the skin of a host.

63. the adapter body includes an ejection portion configured to eject at least a portion of the on-skin medical device from the adapter body; 63. The system of any one of claims 46 to 62, wherein the applicator includes an ejection actuator configured to eject the on-skin medical device from the adapter body.

64. 64. The system of any one of claims 46 to 63, further comprising the on-skin medical device.

65. 65. The system of claim 64, wherein the on-skin medical device includes a mating mismatch with the applicator.

66. 66. The system of claim 64 or 65, wherein the on-skin medical device has a wearable housing having a configuration different from the configuration of the wearable housing into which the engaging portion of the applicator is configured to mate.

67. 67. The system of claim 66, wherein the wearable housing of the on-skin medical device has a smaller diameter or height than the configuration of the wearable housing into which the engaging portion of the applicator is configured to mate.

68. 68. The system of any one of claims 64 to 67, wherein the on-skin medical device comprises a transcutaneous analyte sensor.

69. The system of any one of claims 46 to 68, wherein the adapter body includes an actuation body for electrically actuating the on-skin medical device.

70. 70. The device of claim 69, wherein the actuating body comprises a magnet.

71. A method comprising utilizing an applicator to apply an on-skin medical device to the skin of a host, wherein an adapter body interfaces between at least a portion of the on-skin medical device and the applicator.

72. 72. The method of claim 71, wherein the on-skin medical device includes a mating mismatch with the applicator.

73. 73. The method of claim 71 or 72, wherein the adapter body adapts at least the portion of the on-skin medical device to fit into an engagement portion of the applicator.

74. 74. The method of any one of claims 71 to 73, wherein the on-skin medical device is a first on-skin medical device, and the applicator has an engagement portion configured to engage with a second on-skin medical device having a different configuration than the first on-skin medical device.

75. 75. The method of claim 74, wherein the engaging portion is configured to engage with a wearable housing of the second on-skin medical device having a larger diameter or height than the wearable housing of the first on-skin medical device.

76. 76. The method of any one of claims 71 to 75, further comprising the step of releasing the on-skin medical device from the adapter body.

77. 77. The method of claim 76, further comprising utilizing one or more releasable couplers to release the on-skin medical device from the adapter body.

78. 78. The method of claim 76 or 77, further comprising the step of retaining the adapter body on the applicator after release of the on-skin medical device from the adapter body.

79. 79. The method of any one of claims 71 to 78, wherein the on-skin medical device comprises a transcutaneous analyte sensor.

80. 80. The method of claim 79, further comprising utilizing an insertion element of the applicator to guide the transcutaneous analyte sensor into the skin of the host.

81. 81. The method of any one of claims 71 to 80, further comprising the step of electrically activating the on-skin medical device using an activation body disposed on the adapter body.

82. 82. The method of claim 81, wherein the actuating body comprises a magnet.

83. 83. The method of claim 81 or 82, wherein electrically activating the on-skin medical device comprises activating the on-skin medical device from a low power state to a high power state.

84. A method according to any one of claims 81 to 83, wherein the step of electrically activating the on-skin medical device comprises increasing the distance between the on-skin medical device and the activation body.

85. The method of any one of claims 71 to 84, wherein the adapter body includes one or more walls defining a holding area for receiving at least the portion of the on-skin medical device, and the actuation body is positioned on at least one of the one or more walls.

Images