Methods for reversible male birth control

Abstract

Methods for contraception and reversible male birth control are disclosed herein. One method (1100) includes providing (1102) a polymer (202) comprising a viscosity and reducing (1104) the viscosity of the polymer (202) to produce a polymer solution (200). The method (1100) further includes injecting (1106) the polymer solution (200) into the vas deferens (30) of a male subject while the viscosity of the polymer (202) is being reduced. The polymer solution (200) forms a polymer barrier (10) within the vas deferens (30) to physically block the outflow of sperm within the vas deferens after injection.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 336,219, filed April 28, 2022, the entire contents of which are incorporated herein by reference.

[0002] The subject matter disclosed herein relates to contraceptives, and more specifically, to methods for reversible male birth control. [Background technology]

[0003] Women usually bear most of the economic and health-related burden of unintended pregnancy and / or all of the economic and / or health-related burden of contraceptives. Long-term reversible contraceptives, such as intrauterine devices (IUDs) and implantable sustained-release birth control pills, have become popular methods for birth control among women. No equivalent method of male contraception exists, which affects pregnancy rates around the world. Summary of the Invention [Problem to be solved by the invention]

[0004] The subject matter of the present disclosure provides an example of a method for male birth control. It is desirable to develop an improved method for using polymers that can provide contraception to male subjects (e.g., male humans, non-reproductive humans, male animals, non-reproductive animals, etc.) and / or a method for male birth control. It is also desirable that the contraceptive and / or method for male birth control for male subjects is reversible. Thus, the subject matter of the present application was developed in response to the current state of the art, in particular the desire to provide a contraceptive and / or method for male birth control that is reversible for male subjects. [Means for solving the problem]

[0005] A method for male birth control is disclosed herein. One method includes providing a polymer containing a viscosity, reducing the viscosity of the polymer to create a polymer solution, and injecting the polymer solution into a subject's vas deferens while the viscosity of the polymer is reduced to form a polymer barrier against sperm in the vas deferens after injection. The preceding subject matter of this paragraph characterizes Example 1 of the present disclosure.

[0006] Providing the polymer includes providing a biocompatible polymer. The preceding subject matter of this paragraph characterizes Example 2 of the present disclosure, which also includes subject matter according to Example 1 above.

[0007] Providing a biocompatible polymer includes providing a polysaccharide. The preceding subject matter of this paragraph characterizes Example 3 of the present disclosure, which also includes subject matter according to any one of Examples 1 or 2 above.

[0008] Providing the polysaccharide includes providing an alginate. The preceding subject matter of this paragraph features Example 4 of the present disclosure, which also includes subject matter according to any one of Examples 1, 2, or 3 above.

[0009] Providing an alginate includes providing sodium alginate. The preceding subject matter of this paragraph characterizes Example 5 of the present disclosure, which also includes subject matter according to any one of Examples 1, 2, 3, or 4 above.

[0010] Reducing the viscosity of the polymer includes reducing the viscosity of the polymer so that the polymer solution can be dispensed through a small gauge hypodermic needle. The preceding subject matter of this paragraph characterizes Example 6 of the present disclosure, which also includes subject matter according to Example 1 above.

[0011] Small gauge hypodermic needles include hypodermic needles including gauges up to and including 27 gauge. The preceding subject matter of this paragraph characterizes Example 7 of the present disclosure, which also includes subject matter according to any one of Examples 1 and 6 above.

[0012] Injecting the polymer solution includes injecting the polymer solution into the subject's vas deferens using a small gauge hypodermic needle while the viscosity of the polymer is decreasing. The preceding subject matter of this paragraph features Example 8 of the present disclosure, which also includes subject matter according to any one of Examples 1, 6, and 7 above.

[0013] Reducing the viscosity of the polymer includes temporarily reducing the viscosity of the polymer. The preceding subject matter of this paragraph characterizes Example 9 of the present disclosure, which also includes subject matter according to Example 1 above.

[0014] Temporarily reducing the viscosity of the polymer includes mixing the polymer with glucono-delta-lactone (GdL) to create a polymer solution. The preceding subject matter of this paragraph characterizes Example 10 of the present disclosure, which also includes subject matter according to any one of Examples 1 and 9 above.

[0015] The polymer solution forms a polymer barrier against the sperm in response to being present in the vas deferens for a predetermined time, the predetermined time being time for the subject to metabolize the GdL. The preceding subject matter of this paragraph features Example 11 of the present disclosure, which also includes subject matter according to any one of Examples 1, 9, and 10 above.

[0016] The polymer solution forms a polymer barrier against the sperm, allowing time for the subject to metabolize the polymer. The preceding subject matter of this paragraph characterizes Example 12 of the present disclosure, which also includes subject matter according to Example 1 above.

[0017] This time period is at least one year. The preceding subject matter of this paragraph characterizes Example 13 of the present disclosure, which also includes subject matter according to Example 1 above.

[0018] The method also includes injecting a calcium chelator into the vas deferens to degrade the polymer barrier. The preceding subject matter of this paragraph characterizes Example 14 of the present disclosure, which also includes subject matter according to Example 1 above.

[0019] Injecting a calcium chelator into the vas deferens includes injecting ethylenediaminetetraacetic acid (EDTA) into the vas deferens. The preceding subject matter of this paragraph features Example 15 of the present disclosure, and Example 14 also includes subject matter according to any one of Examples 1 and 14 above.

[0020] Injecting the EDTA into the vas deferens includes injecting the EDTA into the vas deferens via a hypodermic needle having a gauge of 27 or less. The preceding subject matter of this paragraph features Example 16 of the present disclosure, which also includes subject matter according to any one of Examples 1, 14, and 15 above.

[0021] Also disclosed herein is another method for male birth control. The method includes locating a polymer barrier to sperm in a subject's vas deferens and injecting a calcium chelator into the vas deferens to degrade the polymer barrier. The preceding subject matter of this paragraph characterizes Example 17 of the present disclosure.

[0022] Calcium chelators include ethylenediaminetetraacetic acid (EDTA).The preceding subject matter of this paragraph characterizes Example 18 of the present disclosure, which also includes subject matter according to Example 17 above.

[0023] In addition, a further method for male birth control is disclosed herein, which comprises: reducing the viscosity of a polymer to produce a polymer solution; injecting the polymer solution into a subject's vas deferens while the viscosity of the polymer is reduced, and producing a polymer barrier to sperm in the vas deferens after the viscosity of the polymer increases while in the vas deferens; identifying the location of the polymer barrier in the vas deferens; and injecting a calcium chelator into the vas deferens to degrade the polymer barrier. The preceding subject matter of this paragraph characterizes Example 19 of the present disclosure.

[0024] The polymer comprises sodium alginate and the calcium chelator comprises ethylenediaminetetraacetic acid (EDTA).The preceding subject matter of this paragraph characterizes Example 20 of the present disclosure, which also includes subject matter according to Example 19 above.

[0025] A more particular description of the embodiments briefly described above will be made with reference to specific embodiments illustrated in the accompanying drawings, in which the embodiments will be described and explained with additional specificity and detail, with the understanding that these drawings depict only certain embodiments and therefore should not be considered limiting in scope, and in which: [Brief description of the drawings]

[0026] [Figure 1] FIG. 1 is a schematic diagram of a prior art polymeric barrier to sperm in the vas deferens of a male subject.

[0027] [Diagram 2] FIG. 2 is a schematic diagram of one embodiment of a polymer solution that can be inserted via a small gauge needle into the vas deferens of a male subject to form the polymer barrier shown in FIG. 1.

[0028] [Diagram 3] FIG. 2 is a schematic diagram of one embodiment of a calcium chelator capable of degrading the polymer barrier shown in FIG. 1.

[0029] [Figure 4] FIG. 1 is a schematic diagram of one embodiment of a polymeric barrier against sperm containing a spermicide.

[0030] [Diagram 5] FIG. 5 is a schematic diagram of one embodiment of a polymer solution comprising a polymer and a spermicide that can be inserted into the vas deferens of a male subject to form the polymer barrier of FIG.

[0031] [Figure 6]FIG. 5 is a schematic diagram illustrating one embodiment of a particle containing a spermicide contained in the polymer barrier of FIG.

[0032] [Figure 7] FIG. 7 is a schematic diagram illustrating one embodiment of the particle of FIG. 6 showing multiple pores for encapsulating spermicide.

[0033] [Figure 8] FIG. 5 is a schematic diagram of another embodiment of a spermicide-containing polymer solution that can be inserted into the vas deferens of a male subject to form the spermicide-containing polymer barrier of FIG.

[0034] [Figure 9] FIG. 5 is a schematic diagram of one embodiment of a calcium chelator capable of degrading the polymer barrier of FIG.

[0035] [Figure 10A] 5 is a graph illustrating the concentration over about one year of one embodiment of a spermicide contained in the polymeric barrier of FIG. [Figure 10B] 5 is a graph illustrating the concentration over about one year of one embodiment of a spermicide contained in the polymeric barrier of FIG.

[0036] [Figure 11] FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. [Figure 12] FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. [Figure 13] FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. [Figure 14] FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. [Figure 15] FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. [Figure 16] FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. [Figure 17]FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. [Figure 18] FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. [Figure 19] FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. [Figure 20] FIG. 1 is a schematic flow diagram of various methods of reversible male birth control. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Various embodiments disclosed herein provide reversible methods for reversible birth control for male subjects (e.g., male humans, non-reproductive humans, male animals, etc.) Reversible contraceptives for male subjects are also disclosed herein.

[0038] Various embodiments disclosed herein provide, among other things, a barrier (or implant) that provides a less traumatic long-term male contraceptive. The barrier is injected or otherwise placed into the vas deferens of a male subject (e.g., a male human, a non-reproductive human, a male animal, a non-reproductive animal, etc.) to block the outflow of sperm. Other embodiments provide a barrier that includes a spermicide, which can provide a dual barrier defense: a physical block and a chemical defense.

[0039] The barrier can include a polymer or polymer matrix that blocks the vas deferens and, in some embodiments, can further support a sperm inhibitor as a secondary defense. The polymer can be a biocompatible polymer, such as a polysaccharide (e.g., an alginate (e.g., sodium alginate)). The barrier blocks or at least partially blocks the vas deferens and, in some embodiments, can further provide a sperm inhibitor to incapacitate (e.g., kill) sperm that pass through the barrier. In certain embodiments, the sperm inhibitor comprises a calcium blocker sperm inhibitor encapsulated in microparticles suspended in a semi-porous hydrogel polymer.

[0040] Objectives of various embodiments include providing a reversible male contraceptive; providing a male contraceptive that does not completely block the vas deferens; providing a male contraceptive that partially occludes the vas deferens with spermicidal agents; providing a particulate polymer plug for male contraception; providing male contraception via a minimally invasive outpatient procedure; providing a cost-effective reversible male contraceptive; providing a male contraceptive with improved recovery rates; providing a hormone-free male contraceptive, a male contraceptive with an effective life span of at least one year; and providing a male contraceptive with partial occlusion that avoids granulomas in the vas deferens. The present invention may include, but is not limited to, providing a fertility drug, providing a male contraceptive with multiple mechanisms of action (e.g., semi-permeable barrier and spermicide drug), providing a spermicidal drug soluble in an organic solvent or viscosity reducing agent, providing a spermicidal implant that degrades predictably in the body over time, providing a barrier that is both a physical barrier and a chemical / drug delivery device, providing a polymer that can be injected into the vas deferens with a 27 gauge needle or smaller, providing a barrier without damaging the vas deferens, and providing a barrier that includes a spermicide without damaging the vas deferens. The above and other objects may be achieved using a barrier that at least partially blocks / occludes the vas deferens and may further include a sperm inhibitor to neutralize sperm that are not blocked / occluded by the barrier. The barrier may include a scaffold to fix the barrier in place within the vas deferens.

[0041] 1 is a schematic diagram of a prior art polymeric barrier 10 for blocking and / or occluding the outflow of sperm 20 within the vas deferens 30 of a male subject. The polymeric barrier 10 is typically injected into the vas deferens 30 using a hypodermic needle.

[0042] The current polymers forming the polymeric barrier 10 typically include a relatively high viscosity. Typically, a 25 gauge or larger hypodermic needle is required to inject the current polymers into the vas deferens 30 to form the polymeric barrier 10.

[0043] Larger hypodermic needles (e.g., 25 gauge or larger needles) typically require a relatively large incision in the male subject's scrotum to access the vas deferens 30. Additionally, 25 gauge or larger hypodermic needles may leave a relatively large puncture hole in the vas deferens 30, which may predispose the subject to infection, may predispose the subject to granulomas caused by sperm 20 leaking from the vas deferens 30, may require sutures to close, and / or may require longer healing times compared to smaller gauge hypodermic needles.

[0044] 2 is a schematic diagram of one embodiment of a polymer solution 200 capable of forming a polymer barrier 10 (see FIG. 1) for blocking sperm 20 within the vas deferens 30 of a male subject. In various embodiments, a first portion of the polymer solution 200 includes a polymer 202 (e.g., a liquid and / or liquefiable polymer) and a second portion of the polymer solution 200 includes a viscosity reducing agent 204.

[0045] The polymer 202 may include any suitable polymer(s) now known or later developed that may be inserted into the male subject's vas deferens 30 and form a polymeric barrier 10 to block the outflow of sperm 20. The polymer 202 may include liquid and / or solid chemical states. The polymer 202, in various embodiments, includes hydrogels, starches, algae (e.g., brown algae), collagen, gelatin, fibrin, and the like, among other possible suitable polymers and / or substances, each of which are contemplated herein. In certain embodiments, the polymer 202 includes natural polymeric materials and / or substances.

[0046] In various embodiments, the polymer 202 is biocompatible. In some embodiments, the biocompatible polymer 202 includes a polysaccharide, which can include any suitable polysaccharide. A polysaccharide can include a carbohydrate formed by many sugar units (e.g., 10 or more monosaccharides), which includes carbon (C), hydrogen (H), and oxygen (O) in a 1:2:1 ratio.

[0047] In certain embodiments, the polysaccharide comprises an alginate, which may comprise any suitable alginate. The alginate comprises (1,4) linked β-d-mannuronic acid and α-L-guluronic acid in pyranose conformation arranged in homogeneous (e.g., MM or GG) and heterogeneous (e.g., MG or GM) blocks. In one embodiment, the alginate comprises sodium alginate (NaC6H7O6), among other suitable alginates possible and contemplated herein.

[0048] In various embodiments, polymer 202 includes any polymeric substance(s) and / or type(s) of polymer that includes a viscosity that can be temporarily lowered. In additional or alternative embodiments, polymer 202 includes any polymeric substance(s) and / or type(s) of polymer that includes a viscosity that can be temporarily lowered and then increased. Thus, each of these polymers 202 can be considered a gelling polymer 202.

[0049] The viscosity reducing agent 204 may include any suitable substance(s) capable of temporarily reducing the viscosity of the polymer 202 contained in the polymer solution 200. In various embodiments, the viscosity reducing agent 204 may temporarily reduce the viscosity of the polymer 202 such that the polymer solution 200 may be injected into the vas deferens 30 using a 27 gauge hypodermic needle or smaller. Additionally, the viscosity reducing agent 204 may include any suitable substance(s) capable of being metabolized by the male subject such that the viscosity of the polymer 202 increases to form the polymer barrier 10 within the vas deferens. In certain embodiments, the viscosity reducing agent 204 may be selected from the group consisting of gluconolactone (CH 10 In additional or alternative embodiments, the viscosity reducing agent 204 includes calcium chloride, phosphates, lactates, acetates, aluminum, calcium compounds, barium compounds, and / or the like.

[0050] The viscosity reducing agent 204 used to create the polymer solution 200 may depend on the polymer 202 used to form the polymeric barrier 10. Similarly, the type of viscosity reducing agent 204 used in the polymer solution 200 may depend on the type of polymer 202 used to form the polymeric barrier 10. Additionally, the type of viscosity reducing agent 204 and / or viscosity reducing agent 204 used in the polymer solution 200 may depend on the type of polymer 202 and / or polymer 202 used to form the polymeric barrier 10.

[0051] The ratio of polymer 202 to viscosity reducing agent 204 in the polymer solution 200 may include any suitable ratio that allows the viscosity reducing agent 204 to temporarily reduce the viscosity of the polymer 202 such that a 27 gauge needle or smaller may be used to inject the polymer solution 200 into the vas deferens 30. Additionally or alternatively, the ratio of polymer 202 to viscosity reducing agent 204 in the polymer solution 200 may include any suitable ratio that allows the viscosity reducing agent 204 to be metabolized within the vas deferens 30 such that the temporarily reduced viscosity of the polymer 202 may be increased within the vas deferens 30 such that the male subject forms a polymer barrier 10 within the vas deferens 30 in response to metabolizing the viscosity reducing agent 204.

[0052] The ratio of polymer 202 to viscosity reducing agent 204 used in the polymer solution 200 may depend on the polymer 202 used to form the polymeric barrier 10. Similarly, the ratio of polymer 202 to viscosity reducing agent 204 used in the polymer solution 200 may depend on the type of polymer 202 used to form the polymeric barrier 10. Additionally, the ratio of polymer 202 to viscosity reducing agent 204 used in the polymer solution 200 may depend on the type of polymer 202 and / or polymer 202 used to form the polymeric barrier 10.

[0053] Exemplary ratios of polymer 202 to viscosity reducing agent 204 in polymer solution 200 can include, but are not limited to, 10:1, 7:1, 5:1, 4:1, 3:1, 2:1, and 1:1, among other possible ratios, each of which are contemplated herein. In one non-limiting example of a polymer solution 200 that includes sodium alginate and GdL, the ratio of sodium alginate to GdL is 1:1, or equal amounts of sodium alginate and GdL.

[0054] The amount of polymer solution 200 injected into the vas deferens 30 can be any suitable amount of polymer solution 200 capable of forming a polymer barrier 10 within the vas deferens 30 sufficient to block the outflow of sperm 20. In various embodiments, the amount of polymer solution 200 injected into the vas deferens 30 is within the range of about 1 gram (1 g) to about 3 grams (3 g) by weight and / or within the range of about 1 milliliter (1 mL) or 1 cubic centimeter (1 cc) to about 3 milliliters (3 mL) or 3 cubic centimeters (3 cc) by volume, each of other ranges and / or amounts of possible polymer solution 200 contemplated herein. In certain embodiments, the amount of polymer solution 200 injected into the vas deferens 30 is about 2 grams (2 g) by weight and / or about 2 milliliters (2 mL) or 2 cubic centimeters (2 cc) by volume, each of other amounts of possible polymer solution 200 by weight and / or volume contemplated herein.

[0055] In practice, the polymer solution 200, including the polymer 202 and the viscosity reducing agent 204, is prepared for a small gauge needle (e.g., a needle of 27 gauge or smaller). The viscosity reducing agent 204 acts on the polymer 202 to reduce the viscosity of the polymer 202 and / or the polymer solution 200.

[0056] For insertion of the polymer solution 200, the male subject is prepared by administering a local anesthetic. A small incision is made in the male subject's scrotum and the male subject's vas deferens 30 is identified and isolated. A needle is attached to the angiocatheter and inserted at an angle (e.g., an upward angle) that allows a saline flush technique to be used to ensure the needle is inserted to the correct depth within the vas deferens 30. Leaving the needle in place, the saline syringe is removed and replaced with a contraceptive syringe containing a pre-filled amount of polymer solution 200 and the polymer solution 200 is dispensed into the vas deferens 30.

[0057] The needle is removed (e.g., withdrawn) and the vas deferens 30 is allowed to retract into the scrotum. This procedure is repeated for the male subject's second vas deferens 30. Because the puncture hole is small, no sutures are required and the small incision is allowed to heal naturally. Once in the vas deferens 30, the viscosity reducing agent 204 (e.g., GdL, etc.) is metabolized by the male subject, which increases the viscosity of the polymer 202 and / or returns the polymer 202 to its original and / or natural viscosity that forms the polymer barrier 10 within the vas deferens 30.

[0058] Over time, the male subject metabolizes the polymeric barrier 10, thereby enabling and / or allowing the sperm 20 to flow through and / or out of the previously blocked / occluded vas deferens 30. The time to metabolize the polymeric barrier 10 may vary from individual to individual. In various embodiments, the polymeric barrier 10 can remain effective in blocking the sperm 20 for at least one year and up to about two years.

[0059] 3 is a schematic diagram of one embodiment of a calcium chelator 300 (or chelating agent) for degrading the polymer 202 and / or the polymer barrier 10. The calcium chelator 300 may include any suitable solution(s) and / or substance(s) capable of degrading, dissolving, and / or destroying the polymer 202 and / or the polymer barrier 10.

[0060] Some non-limiting examples of calcium chelators include, but are not limited to, saline solutions (e.g., phosphate buffered saline (PBS)) and / or water (H2O), each of which among other possible chelators and / or substances contemplated herein. In some embodiments, the calcium chelator comprises a solution having a potential pH (pH) ranging from about pH 5 to about pH 10, each of which among other possible pH levels contemplated herein. In certain embodiments, the calcium chelator 300 comprises ethylenediaminetetraacetic acid (EDTA), each of which among other possible solution(s) and / or substance(s) contemplated herein.

[0061] At a desired time, a calcium chelator 300 may be injected / added to the site of the polymer barrier 10 to degrade the polymer 202 and / or the polymer barrier 10. The calcium chelator 300 may act on the polymer 202 and / or the polymer barrier 10 to degrade / break the polymer barrier into particles 302 of the polymer 202, thereby allowing the particles 302 to be washed out of the vas deferens 30.

[0062] The calcium chelator 300 may be injected into the vas deferens 30 and / or polymeric barrier 10 using a needle of any size. In various embodiments, the calcium chelator 300 may be injected using a 27 gauge needle or smaller.

[0063] The amount of calcium chelating agent 300 injected into the vas deferens 30 and / or polymeric barrier 10 can be any suitable amount capable of degrading the polymer 202 and / or polymeric barrier 10 in the vas deferens 30 sufficiently to not impede the outflow of sperm 20. In various embodiments, the amount of calcium chelating agent 300 injected into the vas deferens 30 and / or polymeric barrier 10 ranges from about 2 grams (2g) to about 5 grams (5g) by weight and / or from about 2 mL or 2 cc to about 5 milliliters (5 mL) or 5 cubic centimeters (5 cc) by volume, each among other possible ranges and / or amounts of calcium chelating agent 300 contemplated herein. In certain embodiments, the amount of calcium chelating agent 300 injected into the vas deferens 30 and / or polymeric barrier 10 is about 2 g by weight and / or 2 mL / 2 cc by volume, each among other possible amounts by weight and / or volume contemplated herein.

[0064] The male subject is prepared for insertion of the calcium chelator 300 by administering a local anesthetic. A small incision is made in the male subject's scrotum and the male subject's vas deferens 30 is identified and isolated. The location and / or site of the polymeric barrier 10 is identified and isolated.

[0065] The needle is attached to the angiocatheter and inserted at an angle (e.g., an upward angle) that allows the saline flush technique to be used to ensure the needle is inserted to the correct depth within the vas deferens 30. Leaving the needle in place, the saline syringe is removed and replaced with a syringe containing a pre-filled amount of calcium chelator 300, and calcium chelator 300 is dispensed into the vas deferens 30 and / or polymeric barrier 10 and vas deferens 30, and the vas deferens 30 is flushed with saline solution (e.g., 2 mL / cc of saline solution).

[0066] The needle is removed (e.g., withdrawn) and the vas deferens 30 is allowed to retract into the scrotum. This procedure is repeated for the other polymeric barrier 10 in the second vas deferens 30 of the male subject. No sutures are required because the puncture hole is small, and the small incision is allowed to heal naturally.

[0067] After the polymer 202 and / or polymer barrier 10 have sufficiently degraded and / or have been degraded, the sperm 20 are no longer blocked and can flow through the vas deferens 30. Because the polymer barrier 10 can now be degraded at will, this form of male birth control is considered to be temporary and / or reversible.

[0068] 4 is a schematic diagram of one embodiment of a polymeric barrier 400 including a spermicide (see spermicide 504 in FIG. 5) that can be injected or otherwise placed into the vas deferens 30 of a male subject. The polymeric barrier 400 can physically block or at least partially block the outflow of sperm 20 within the vas deferens 30, and the spermicide can chemically incapacitate the sperm 20. In this manner, the polymeric barrier 400 can create a two-barrier defense against sperm 20 within the vas deferens 30.

[0069] 5 is a schematic diagram of one embodiment of a polymer solution 500 capable of forming a polymer barrier 400 (see FIG. 4 ) that includes a spermicide to physically block or at least partially block sperm 20 in the vas deferens 30 of a male subject and / or to neutralize sperm 20 in the vas deferens 30. In various embodiments, a first portion of the polymer solution 500 includes a polymer 502 and a second portion of the polymer solution 500 includes a spermicide 504.

[0070] The polymer 502 may include any suitable polymer(s), known or later developed, that can be inserted into the male subject's vas deferens 30 and form a polymeric barrier 400 that physically blocks the outflow of sperm 20. The polymer 502 may include liquid and / or solid chemical states. The polymer 502, in some embodiments, includes a hydrogel, among other possible suitable polymers and / or materials, each of which are contemplated herein.

[0071] In various embodiments, the polymer 502 is biocompatible. In some embodiments, the biocompatible polymer 502 comprises a polysaccharide, which can include any suitable polysaccharide.

[0072] In certain embodiments, the polysaccharide comprises an alginate, which may comprise any suitable alginate, hi one embodiment, the alginate comprises sodium alginate, among other suitable alginates possible and contemplated herein.

[0073] The polymer solution 500 may include any suitable amount of polymer 502 capable of forming a polymer barrier 400 within the vas deferens 30 sufficient to physically block or at least partially block the outflow of sperm 20. In various embodiments, the amount of polymer 502 in the polymer solution 500 is within the range of about 1 g to about 3 g by weight and / or about 1 mL / cc to about 3 mL / cc by volume, each of other ranges and / or amounts of possible polymer 502 contemplated herein. In certain embodiments, the amount of polymer 502 in the polymer solution 500 is about 2 g by weight and / or about 2 mL / cc by volume, each of other amounts of possible polymer 502 by weight and / or volume contemplated herein.

[0074] Spermicide 504 may include any suitable substance or substances capable of neutralizing (e.g., killing) sperm 20. In certain embodiments, spermicide 504 may include a sperm inhibitor or other mechanism capable of neutralizing sperm 20.

[0075] In various embodiments, spermicide 504 can include any suitable chemical, drug, hormone, element, and / or other composition capable of neutralizing sperm 30. In various embodiments, spermicide 504 includes a calcium channel blocker, an essential oil (e.g., neem oil, etc.), and / or citric acid, among other possible substance(s), each of which are contemplated herein. In one embodiment, the calcium channel blocker includes nifedipine, among other possible channel blockers, each of which are contemplated herein. In additional or alternative embodiments, spermicide 504 includes an acid (e.g., a pH of less than 7 pH).

[0076] In various embodiments, the concentration of spermicide 504 may be maintained within the polymeric barrier 400 for approximately one year (see Figures 10A and 10B). That is, Figures 10A and 10B show the concentration of one embodiment of spermicide 504 in the polymeric barrier 400 over a period of approximately one year.

[0077] The polymer solution 500 may include any suitable amount of spermicide 504 capable of neutralizing sperm 20. In certain embodiments, the amount of spermicide 504 in the polymer solution 500 is about 4.676 le, among other higher or lower concentrations of spermicide 504 possible, each of which is contemplated herein. -7 mol / m 3 (See Figures 10A and 10B).

[0078] 6, the spermicide 504 is contained and / or stored within a plurality of particles 600, which may be contained / dispersed within the polymer solution 500. The particles 600 are configured to encapsulate the spermicide 504 such that the spermicide 504 can interact with and neutralize the sperm 20 that contact the polymer barrier 400.

[0079] 6 illustrates one embodiment of a particle 600 including a spermicide 504. The particle 600 may be composed of any suitable material capable of accommodating the spermicide 504. In various embodiments, the particle 600 includes a polymer and / or a biocompatible polymer. In certain embodiments, the microparticle 600 includes poly-L-lactic acid (PLLA) and / or poly(lactic-co-glycolic acid) (PLGA), among other possible polymers, each of which are contemplated herein.

[0080] Particles 600 may include any suitable size and / or shape capable of accommodating spermicide 504. In certain embodiments, particles 600 may be in the range of micro (10 mm) to 100 mm, among other possible larger and / or smaller sizes, each of which are contemplated herein. -6 meters) and / or nano (10 -9 Includes sizes in metric (metric) scale.

[0081] 7, the microparticle 600 includes a plurality of pores 702 configured to encapsulate the spermicide 504. The pores 702 may include any suitable size and / or shape that allows / permits the spermicide to reside therein.

[0082] In certain embodiments, the pores 702 include a size and / or gap of about five nanometers (5 nm). The pores 702 can be filled with the spermicide 504 via physical and / or chemical bonds to encapsulate the spermicide 504 for an effective period of up to one year (see FIGS. 10A and 10B).

[0083] 5, a polymer solution 500 including a polymer 502 and a spermicide 504 is prepared in a hypodermic needle for injection into the male subject's vas deferens 30. The needle may include any size needle capable of delivering the polymer solution 500 to the vas deferens 30.

[0084] To create a polymer barrier 400 within the vas deferens 30 using the polymer solution 500, the male subject is prepared by administering a local anesthetic. An incision is made in the male subject's scrotum and the male subject's vas deferens 30 is identified and isolated. A needle is attached to the angiocatheter and inserted at an angle (e.g., an upward angle) that allows a saline flush technique to be used to ensure the needle is inserted to the correct depth within the vas deferens 30. Leaving the needle in place, the saline syringe is removed and replaced with a contraceptive syringe containing a pre-filled amount of polymer solution 500, and the polymer solution 500 is dispensed into the vas deferens 30.

[0085] The needle is removed (e.g., withdrawn) and the vas deferens 30 is allowed to retract into the scrotum. This procedure is repeated for the second vas deferens 30 of the male subject. In this manner, a polymeric barrier 400 containing spermicide 504 is created within each vas deferens 30 of the male subject.

[0086] Over time, the male subject may metabolize the polymeric barrier 400, polymer 502, and / or spermicide 504, which may enable and / or allow sperm 20 to flow through and / or out of the vas deferens 30. The time to metabolize the polymeric barrier 400, polymer 502, and / or spermicide 504 may vary from individual to individual. In various embodiments, the polymeric barrier 400, polymer 502, and / or spermicide 504 may remain effective in blocking and / or incapacitating sperm 20 for at least one year and up to about two years.

[0087] 8 is a schematic diagram of another embodiment of a polymer solution 800 capable of forming a polymer barrier 400 (see FIG. 4 ) that includes a spermicide to physically block or at least partially block sperm 20 in the vas deferens 30 of a male subject and / or neutralize sperm 20 in the vas deferens 30. In various embodiments, a first portion of the polymer solution 800 includes a polymer 202, a second portion of the polymer solution 800 includes a viscosity reducing agent 204, and a third portion of the polymer solution 800 includes a spermicide 504.

[0088] The polymer 202 may include any of the embodiments of the polymer 202 included in the polymer solution 200 discussed with reference to Figure 2. The viscosity reducing agent 204 may include any of the embodiments of the viscosity reducing agent 204 included in the polymer solution 200 discussed with reference to Figure 2. The spermicide 504 may include any of the embodiments of the spermicide 504 included in the polymer solution 500 discussed with reference to Figure 5.

[0089] To use the polymer solution 800 to create a polymer barrier 400 within the vas deferens 30, the polymer solution 800 is placed in a small gauge needle (e.g., a 27 gauge needle or smaller). The viscosity reducing agent 204 acts on the polymer 202 containing the spermicide 504 to reduce the viscosity of the polymer 202 and / or the polymer solution 800.

[0090] For insertion of the polymer solution 800, the male subject is prepared by administering a local anesthetic. A small incision is made in the male subject's scrotum and the male subject's vas deferens 30 is identified and isolated. A needle is attached to the angiocatheter and inserted at an angle (e.g., an upward angle) that allows a saline flush technique to be used to ensure the needle is inserted to the correct depth within the vas deferens 30. Leaving the needle in place, the saline syringe is removed and replaced with a contraceptive syringe containing a pre-filled amount of polymer solution 800 and the polymer solution 800 is dispensed into the vas deferens 30.

[0091] The needle is removed (e.g., withdrawn) and the vas deferens 30 is allowed to retract into the scrotum. This procedure is repeated for the male subject's second vas deferens 30. The small puncture hole does not require sutures and the small incision is allowed to heal naturally. Once in the vas deferens 30, the viscosity reducing agent 204 (e.g., GdL, etc.) is metabolized by the male subject, which increases the viscosity of the polymer 202 and / or returns the polymer 202 to its original and / or natural viscosity, thereby forming a polymer barrier 400 within the vas deferens 30.

[0092] Over time, the male subject metabolizes the polymeric barrier 400, polymer 202, and / or spermicide 504, which allows and / or may allow sperm 20 to flow through and / or out of the previously blocked / occluded vas deferens 30. The time to metabolize the polymeric barrier 400, polymer 202, and / or spermicide 504 may vary from individual to individual. In various embodiments, the polymeric barrier 400 and / or spermicide 504 may remain effective for at least one year and up to two years.

[0093] 9 is a schematic diagram of one embodiment of a calcium chelator 900 for degrading the polymeric barrier 400 and / or the spermicide 504. The calcium chelator 900 may include any suitable solution(s) and / or substance(s) capable of degrading, dissolving, and / or destroying the polymeric barrier 400 and / or the spermicide 504. In certain embodiments, the calcium chelator 900 includes ethylenediaminetetraacetic acid (EDTA), among other possible solution(s) and / or substance(s), each of which are contemplated herein.

[0094] At a desired time, a calcium chelating agent 900 may be injected / added to the site of the polymeric barrier 400 to degrade the polymer 202 and / or spermicide 504. The calcium chelating agent 900 may act on the polymer 202 and / or spermicide 504 to degrade / break the polymeric barrier 400 into particles 902 of the polymer 202 and / or spermicide 504, thereby allowing the particles 902 to be washed out of the vas deferens 30.

[0095] The calcium chelating agent 900 may be injected into the vas deferens 30 and / or polymeric barrier 400 using a needle of any size. In various embodiments, the calcium chelating agent 900 may be injected using a 27 gauge needle or smaller.

[0096] The amount of calcium chelating agent 900 injected into the vas deferens 30 and / or polymeric barrier 400 can be any suitable amount capable of degrading the polymer 202 and / or spermicide 504 in the vas deferens 30 sufficiently to not impede the outflow of sperm 20. In various embodiments, the amount of calcium chelating agent 900 injected into the vas deferens 30 and / or polymeric barrier 900 is within the range of about 2 g to about 5 g by weight and / or 2 ml / cc to about 5 mL / cc by volume, each of other possible ranges and / or amounts of calcium chelating agent 300 contemplated herein. In certain embodiments, the amount of calcium chelating agent 900 injected into the vas deferens 30 and / or polymeric barrier 400 is about 2 g by weight and / or 2 mL / cc by volume, each of other possible amounts by weight and / or volume contemplated herein.

[0097] The male subject is prepared for insertion of the calcium chelator 900 by administering a local anesthetic. A small incision is made in the male subject's scrotum and the male subject's vas deferens 30 is identified and isolated. The location and / or site of the polymer barrier 400 is identified and isolated.

[0098] The needle is attached to the angiocatheter and inserted at an angle (e.g., an upward angle) that allows the saline flush technique to be used to ensure that the needle is inserted to the correct depth within the vas deferens 30. Leaving the needle in place, the saline syringe is removed and replaced with a syringe containing a pre-filled amount of calcium chelator 900, and the calcium chelator 900 is dispensed into the vas deferens 30 and / or polymeric barrier 400, followed by flushing with saline solution, as in other embodiments discussed elsewhere herein.

[0099] The needle is removed (e.g., withdrawn) and the vas deferens 30 is allowed to retract into the scrotum. This procedure is repeated for the other polymer barrier 400 in the second vas deferens 30 of the male subject. No sutures are required because the puncture hole is small, and the small incision is allowed to heal naturally.

[0100] After the polymer barrier 400 and / or spermicide 504 have sufficiently degraded, the sperm 20 are no longer blocked and are able to flow through the vas deferens 30. Because the polymer barrier 400 and spermicide 504 can now be degraded at will, this form of male birth control is considered to be temporary and / or reversible.

[0101] 11 is a block diagram of one embodiment of a method 1100 for male birth control. In at least the illustrated embodiment, the method 1100 can begin with providing a polymer 202 comprising clay (block 1102). In various embodiments, providing the polymer 202 includes providing a biocompatible polymer, providing a polysaccharide, providing an alginate, and / or providing sodium alginate.

[0102] The method 1100 further includes reducing the viscosity of the polymer 202 (block 1104) to create the polymer solution 200. In various embodiments, the viscosity of the polymer 202 is reduced and / or the viscosity of the polymer 202 is reduced and / or the polymer solution 200 is created by mixing and / or adding a viscosity reducing agent 204 (e.g., GdL) to the polymer 202.

[0103] The polymer solution 200 is injected into the male subject's vas deferens 30 while the viscosity of the polymer 202 is decreasing (block 1106). In various embodiments, the polymer solution 200 forms a polymer barrier 10 against sperm after being injected into the vas deferens 30. The method 1100 can provide temporary and / or reversible male birth control.

[0104] 12 is a block diagram of another embodiment of a method 1200 for male birth control. In at least the illustrated embodiment, the method 1200 can begin with providing a polymer 202 comprising clay (block 1202). In various embodiments, providing the polymer 202 includes providing a biocompatible polymer, providing a polysaccharide, providing an alginate, and / or providing sodium alginate.

[0105] The method 1200 further includes reducing the viscosity of the polymer 202 (block 1204) to create the polymer solution 200. In various embodiments, the viscosity of the polymer 202 is reduced and / or the polymer solution 200 is created by mixing and / or adding a viscosity reducing agent 204 (e.g., GdL) to the polymer 202.

[0106] The polymer solution 200, 800 is injected into the male subject's vas deferens 30 while the viscosity of the polymer 202 is decreasing (block 1206). In various embodiments, the polymer solution 200 forms a polymer barrier 10 against sperm after being injected into the vas deferens 30.

[0107] A calcium chelator 300 (e.g., EDTA) is injected into the vas deferens 30 to degrade the polymer barrier 10 (block 1208). The calcium chelator 300 can be injected using any size needle, and in some embodiments, a 27 gauge needle or smaller. In various embodiments, the method 1200 can provide temporary and / or reversible male birth control.

[0108] 13 is a block diagram of a further embodiment of a method 1300 for male birth control. In at least the illustrated embodiment, the method 1300 can begin with providing a polymer 502 and a spermicide 504 to form a polymer solution 500 (block 1302).

[0109] In various embodiments, providing the polymer 502 includes providing a biocompatible polymer, providing a polysaccharide, providing an alginate, and / or providing sodium alginate. Additionally, the spermicide 504 can include a calcium channel blocker and / or nifedipine, as discussed elsewhere herein.

[0110] A polymer solution 500 including a polymer 502 and a spermicide 504 is injected into the male subject's vas deferens 30 (block 1304). In various embodiments, the polymer solution 500 can form a polymer barrier 400 after being injected into the vas deferens 30. The method 1300 can provide temporary and / or reversible male birth control.

[0111] 14 is a block diagram of another embodiment of a method for male birth control 1400. In at least the illustrated embodiment, the method 1400 can begin with providing a polymer 502 and a spermicide 504 to form a polymer solution 500 (block 1402).

[0112] In various embodiments, providing the polymer 502 includes providing a biocompatible polymer, providing a polysaccharide, providing an alginate, and / or providing sodium alginate. Additionally, the spermicide 504 can include a calcium channel blocker and / or nifedipine, as discussed elsewhere herein.

[0113] A polymer solution 500 including a polymer 502 and a spermicide 504 is injected into the male subject's vas deferens 30 (block 1404). In various embodiments, the polymer solution 500 can form a polymer barrier 400 after being injected into the vas deferens 30.

[0114] A calcium chelator 900 (e.g., EDTA) can be injected into the vas deferens 30 (block 1406) to degrade the polymer 502 and / or the spermicide 504. The method 1400 can provide temporary and / or reversible male birth control.

[0115] 15 is a block diagram of an additional embodiment of a method 1500 for male birth control. In at least the illustrated embodiment, the method 1500 can begin with providing the polymer 202 and the spermicide 504 (block 1502).

[0116] In various embodiments, providing the polymer 202 includes providing a biocompatible polymer, providing a polysaccharide, providing an alginate, and / or providing sodium alginate. Additionally, the spermicide 504 can include a calcium channel blocker and / or nifedipine, as discussed elsewhere herein.

[0117] The method 1500 further includes reducing the viscosity of the polymer 202 (block 1504) to create the polymer solution 800. In various embodiments, the viscosity of the polymer 202 is reduced and / or the polymer solution 800 is created by mixing and / or adding a viscosity reducing agent 204 (e.g., GdL) to the polymer 202.

[0118] The polymer solution 800 is injected into the male subject's vas deferens 30 while the viscosity of the polymer 202 is decreasing (block 1506). In various embodiments, the polymer solution 800 forms a polymer barrier 400 against sperm after being injected into the vas deferens 30. The method 1500 can provide temporary and / or reversible male birth control.

[0119] 16 is a block diagram of an additional embodiment of a method 1600 for male birth control. In at least the illustrated embodiment, the method 1600 can begin with providing the polymer 202 and the spermicide 504 (block 1602).

[0120] In various embodiments, providing the polymer 202 includes providing a biocompatible polymer, providing a polysaccharide, providing an alginate, and / or providing sodium alginate. Additionally, the spermicide 504 can include a calcium channel blocker and / or nifedipine, as discussed elsewhere herein.

[0121] The method 1600 further includes reducing the viscosity of the polymer 202 (block 1604) to create the polymer solution 800. In various embodiments, the viscosity of the polymer 202 is reduced and / or the polymer solution 800 is created by mixing and / or adding a viscosity reducing agent 204 (e.g., GdL) to the polymer 202.

[0122] The polymer solution 800 is injected into the male subject's vas deferens 30 while the viscosity of the polymer 202 is decreasing (block 1606). In various embodiments, the polymer solution 800 forms a polymer barrier 400 against sperm after being injected into the vas deferens 30.

[0123] A calcium chelator 900 (e.g., EDTA) can be injected into the vas deferens 30 (block 1606) to degrade the polymer 502 and / or the spermicide 504. The method 1600 can provide temporary and / or reversible male birth control.

[0124] 17 is a block diagram of another embodiment of a method for male birth control 1700. In at least the illustrated embodiment, the method 1700 may begin with locating a polymeric barrier 10 within the vas deferens 30 of a male subject (block 1702).

[0125] The polymer barrier 400 may be located using any suitable method and / or technique now known or later developed that can identify the location of material within the vas deferens 30. In some embodiments, the polymer barrier 400 includes a dye (e.g., a fluorescent dye (e.g., indocyanine green (ICG) or the like)), and visual imaging can be used to identify the location of the polymer barrier 400 via the dye within the polymer barrier 400. In additional or alternative embodiments, ultrasound is used to identify the location of the polymer barrier 400.

[0126] A calcium chelator 300 can be injected (block 1704) into the vas deferens 30 to degrade the polymeric barrier 10. The calcium chelator 300 in various embodiments can include EDTA, among other possible calcium chelators, each of which are contemplated herein.

[0127] 18 is a block diagram of yet another embodiment of a method 1800 for male birth control. In at least the illustrated embodiment, the method 1800 may begin with locating a polymeric barrier 400 within the vas deferens 30 of a male subject (block 1802).

[0128] The polymer barrier 400 may be located using any suitable method and / or technique now known or later developed that can identify the location of material within the vas deferens 30. In some embodiments, the polymer barrier 400 includes a dye (e.g., a fluorescent dye (e.g., indocyanine green (ICG) or the like)), and visual imaging can be used to identify the location of the polymer barrier 400 via the dye within the polymer barrier 400. In additional or alternative embodiments, ultrasound is used to identify the location of the polymer barrier 400.

[0129] A calcium chelating agent 900 can be injected (block 1804) into the vas deferens 30 to degrade the polymeric barrier 400 and / or the spermicide 504. The calcium chelating agent 900 in various embodiments can include EDTA, among other possible calcium chelating agents, each of which is contemplated herein.

[0130] 19 is a block diagram of a further embodiment of a method 1900 for male birth control. In at least the illustrated embodiment, the method 1900 can begin with reducing the viscosity of the polymer 202 to create a polymer solution 200 (block 1902).

[0131] The polymer 202 may include biocompatible polymers, polysaccharides, alginates, and / or sodium alginate, as discussed elsewhere herein. In various embodiments, the viscosity of the polymer 202 is reduced and / or the polymer solution 200 is created by mixing and / or adding a viscosity reducing agent 204 (e.g., GdL) to the polymer 202.

[0132] The polymer solution 200 is injected into the male subject's vas deferens 30 while the viscosity of the polymer 202 is decreasing (block 1904). In various embodiments, the polymer solution 200 forms a polymer barrier 10 against sperm after being injected into the vas deferens 30.

[0133] The polymeric barrier 10 may be located within the vas deferens 30 (block 1906), and a calcium chelator 300 (e.g., EDTA) may be injected into the vas deferens 30 (block 1908) to degrade the polymeric barrier 10. The method 1900 may provide temporary and / or reversible male birth control.

[0134] 20 is a block diagram of an embodiment of a method 2000 for male birth control. In at least the illustrated embodiment, the method 2000 can begin with reducing the viscosity of a polymer 202 that includes a spermicide 504 (block 2002) to create a polymer solution 800.

[0135] The polymer 202 can include a biocompatible polymer, a polysaccharide, an alginate, and / or sodium alginate, as discussed elsewhere herein. Additionally, the spermicide 504 can include a calcium channel blocker and / or nifedipine, as discussed elsewhere herein. In various embodiments, the viscosity of the polymer 202 is reduced and / or the polymer solution 800 is created by mixing and / or adding a viscosity reducing agent 204 (e.g., GdL) to the polymer 202.

[0136] The polymer solution 800 is injected into the male subject's vas deferens 30 while the viscosity of the polymer 202 is decreasing (block 1904). In various embodiments, the polymer solution 800 forms a polymer barrier 400 against sperm after being injected into the vas deferens 30.

[0137] The polymeric barrier 400 may be located within the vas deferens 30 (block 2006), and a calcium chelator 900 (e.g., EDTA) may be injected into the vas deferens 30 (block 2008) to degrade the polymeric barrier 400 and / or the spermicide 504. The method 2000 may provide temporary and / or reversible male birth control.

[0138] Throughout this specification, reference to an embodiment, an embodiment, or similar terms means that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, throughout this specification, the appearance of an embodiment, an embodiment, and similar terms may, but do not necessarily, all refer to the same embodiment, but mean one or more embodiments, unless expressly specified otherwise. The terms including, comprising, having, and variations thereof mean including, but are not limited to, unless expressly specified otherwise. An enumerated list of items does not imply that any or all of the items are mutually exclusive, unless expressly specified otherwise. The terms "a," "an," and "the" refer to one or more, unless expressly specified otherwise.

[0139] Furthermore, the features, structures, or characteristics of the described embodiments may be combined in any suitable manner. However, one skilled in the art will recognize that the embodiments may be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations have not been shown or described in detail to avoid obscuring aspects of the embodiments.

[0140] Aspects of the embodiments are described above with reference to schematic flow chart illustrations and / or schematic block diagrams of particles (e.g., silver particles 100) and methods according to various embodiments. It should also be noted that in some alternative implementations, the functions noted in the blocks may be performed in an order different from that shown in the figures. For example, two blocks shown in succession may in fact be performed substantially simultaneously, or the blocks may be performed in the reverse order, depending on the functionality involved. Other steps and methods may be considered equivalent in function, logic, or effect to one or more blocks of the illustrated figures, or portions thereof.

[0141] Various arrow and line types may be used in the flowcharts and / or block diagrams, but it is understood that they are not intended to limit the scope of the corresponding embodiments. Indeed, some arrows or other connectors may be used to indicate only the logical flow of the depicted embodiments. For example, arrows may indicate waiting or monitoring periods of unspecified duration between recited steps of the depicted embodiments.

[0142] The description of an element in each figure may refer to the element in the proceeding figure. Like numbers refer to like elements in all figures, including alternative embodiments of like elements.

[0143] Various disclosed embodiments may be embodied in other specific forms. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is therefore indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

1. A method of making a polymer solution for use in forming a polymeric barrier in the vas deferens that can be degraded by a calcium chelating agent, the method comprising: providing a polymer; adding a viscosity reducing agent to the polymer to produce a polymer solution of the polymer having a temporarily reduced viscosity prior to injecting the polymer solution into the subject, the polymer solution being suitable for a single injection into the vas deferens of the subject; where: the single injection includes injecting the polymer solution into the vas deferens of the subject while the viscosity of the polymer is temporarily reduced, the viscosity reducing agent of the polymer solution being configured to be metabolized by the subject, and the polymer of the polymer solution remaining in the vas deferens after the viscosity reducing agent is metabolized to form a polymer barrier to sperm in the vas deferens, thereby temporarily infertilizing the subject after a first time period following the single injection into the vas deferens; the polymer barrier formed by the polymer solution is such that, at a desired time point after a second time period has elapsed following the formation of the polymer barrier in the vas deferens that defines a contraceptive period, a calcium chelator is injected directly into the polymer barrier formed in the vas deferens, degrading the polymer barrier and reversing the temporary infertility of the subject at the desired time point; the calcium chelating agent is not injected into the vas deferens prior to the desired time at which reversal of the temporary infertility is desired, and the calcium chelating agent is not present in the vas deferens during the contraceptive period; method.

2. The method of claim 1 , wherein providing the polymer comprises providing a biocompatible polymer.

3. The method of claim 2 , wherein providing the biocompatible polymer comprises providing a polysaccharide.

4. The method of claim 3 , wherein providing the polysaccharide comprises providing an alginate.

5. The method of claim 4 , wherein providing the alginate comprises providing sodium alginate.

6. The method described in claim 1, wherein the viscosity reducing agent comprises glucono-delta-lactone (GdL).

7. The method described in claim 1, wherein injecting the calcium chelating agent directly into the polymer barrier after formation of the polymer barrier in the vas deferens includes injecting ethylenediaminetetraacetic acid (EDTA) directly into the polymer barrier formed in the vas deferens.

8. 8. The method of claim 7, wherein injecting the EDTA directly into the polymeric barrier in the vas deferens comprises injecting the EDTA directly into the polymeric barrier in the vas deferens through a hypodermic needle including a gauge having a size of 27 gauge or less.

9. A method of making a polymer solution for use in forming a polymeric barrier in the vas deferens, said method comprising: providing a polymer; adding a viscosity reducing agent to the polymer to produce a polymer solution of the polymer having a temporarily reduced viscosity prior to injecting the polymer solution into the subject; the polymer solution is suitable for a first single injection into the vas deferens of the subject at a first time when contraception is desired; the first single injection includes injecting the polymer solution into the subject's vas deferens while the viscosity of the polymer is temporarily reduced to create a polymer barrier within the subject's vas deferens; where: the viscosity reducing agent of the polymer solution is configured to be metabolized by the subject, and the polymer of the polymer solution remains in the subject's vas deferens and forms a polymer barrier to sperm in the vas deferens after a first time period, thereby temporarily infertilizing the subject for a contraceptive period following the first single injection, and only the polymer barrier remains in the vas deferens for the contraceptive period. method.

10. The use further comprises: administering a second single injection into the subject's vas deferens at a second time when conception is desired, at least one year after the subject has been temporarily rendered infertile by the creation of the polymeric barrier in the vas deferens; the second single injection comprises injecting a calcium chelator directly into the polymeric barrier within the vas deferens to degrade the polymeric barrier and thereby reverse infertility in the subject; the calcium chelating agent is not injected into the vas deferens prior to the desired time at which reversal of the temporary infertility is desired, and the calcium chelating agent is not present in the vas deferens during the contraceptive period; 10. The method of claim 9.

11. A system comprising a polymer and a viscosity reducing agent for use in forming a polymeric barrier in the vas deferens, said use comprising: a) adding said viscosity reducing agent to said polymer to produce a polymer solution of said polymer having a temporarily reduced viscosity prior to injecting the polymer solution into a subject; b) administering a single injection into the vas deferens of said subject, wherein: the single injection includes injecting the polymer solution into the vas deferens of the subject while the viscosity of the polymer is temporarily reduced, the viscosity-reducing agent of the polymer solution being configured to be metabolized by the subject, and the polymer of the polymer solution remaining in the vas deferens after the viscosity-reducing agent is metabolized to form a polymeric barrier to sperm in the vas deferens, thereby temporarily infertilizing the subject after a first time period following the single injection into the vas deferens; and c) reversing the temporary infertility of the subject at a desired time point after a second time period following the formation of the polymeric barrier within the vas deferens, the time point defining a contraceptive period, by injecting a calcium chelating agent directly into the polymeric barrier formed within the vas deferens to degrade the polymeric barrier. where: the calcium chelating agent is not injected into the vas deferens prior to the desired time at which reversal of the temporary infertility is desired, and the calcium chelating agent is not present in the vas deferens during the contraceptive period; system.

12. A system comprising a polymer and a viscosity reducing agent for use in forming a polymeric barrier in the vas deferens, said use comprising: a) adding said viscosity reducing agent to said polymer to produce a polymer solution of said polymer having a temporarily reduced viscosity prior to injecting the polymer solution into a subject; b) administering a single injection into the vas deferens of said subject, wherein: the single injection comprises injecting the polymer solution into the vas deferens of the subject while the viscosity of the polymer is temporarily reduced, the viscosity reducing agent of the polymer solution being configured to be metabolized by the subject, and the polymer of the polymer solution remaining in the vas deferens after a first time period following the single injection into the vas deferens to form a polymeric barrier to sperm in the vas deferens, thereby temporarily infertilizing the subject; c) locating the polymeric barrier within the vas deferens at a desired time point after a second time period following formation of the polymeric barrier within the vas deferens, the second time period defining a contraceptive period; and d) after locating the polymer barrier within the vas deferens, injecting a calcium chelator directly into the polymer barrier formed within the vas deferens to degrade the polymer barrier, thereby reversing the temporary infertility of the subject at the desired time point. where: the calcium chelating agent is not injected into the vas deferens prior to the desired time at which reversal of the temporary infertility is desired, and the calcium chelating agent is not present in the vas deferens during the contraceptive period; system.

13. A system comprising a polymer and a viscosity reducing agent for use in forming a polymeric barrier in the vas deferens, said use comprising: a) adding said viscosity reducing agent to said polymer to produce a polymer solution of said polymer having a temporarily reduced viscosity prior to injecting the polymer solution into a subject; b) at a first time when contraception is desired, performing a first single injection into the subject's vas deferens, the single injection comprising injecting the polymer solution into the subject's vas deferens while the viscosity of the polymer is temporarily reduced to create a polymer barrier within the subject's vas deferens; where: the viscosity reducing agent of the polymer solution is configured to be metabolized by the subject, and the polymer of the polymer solution remains in the subject's vas deferens and forms a polymer barrier to sperm in the vas deferens after a first time period, thereby temporarily infertilizing the subject for a contraceptive period following the first single injection, and only the polymer barrier remains in the vas deferens for the contraceptive period. system.

14. A system described in any one of claims 11 to 13, wherein the polymer comprises a polysaccharide.

15. The system described in claim 14, wherein the polysaccharide includes alginate.

16. The system described in claim 15, wherein the alginate comprises sodium alginate.

17. A system described in any one of claims 11 to 13, wherein injecting the polymer solution into the subject's vas deferens while the viscosity of the polymer is temporarily reduced comprises injecting the polymer solution into the subject's vas deferens while the viscosity of the polymer is temporarily reduced through a hypodermic needle including a gauge having a size of 27 gauge or less.

18. A system described in any one of claims 11 to 13, wherein the viscosity reducing agent comprises glucono-delta-lactone (GdL).

19. The use further comprises: administering a second single injection into the subject's vas deferens at a second time when conception is desired at least one year after the subject has been temporarily infertile by creating the polymeric barrier within the vas deferens; the second single injection comprises injecting a calcium chelator directly into the polymeric barrier present in the vas deferens to degrade the polymeric barrier and thereby reverse infertility in the subject; where: the calcium chelating agent is not injected into the vas deferens prior to the desired time at which reversal of the temporary infertility is desired, and the calcium chelating agent is not present in the vas deferens during the contraceptive period; The system of claim 13.

20. The system described in claim 11, 12, or 19, wherein directly injecting the calcium chelating agent into the polymer barrier after formation of the polymer barrier in the vas deferens includes directly injecting ethylenediaminetetraacetic acid (EDTA) into the polymer barrier formed in the vas deferens.

21. The viscosity reducing agent comprises glucono-delta-lactone (GdL), the polymer comprises sodium alginate; The calcium chelating agent includes ethylenediaminetetraacetic acid (EDTA).

20. The system of claim 11, 12, or 19.

22. The system described in claim 12, wherein identifying the location of the polymer barrier within the vas deferens includes identifying the location of the polymer barrier within the vas deferens using one of ultrasound or digital visual imaging.

Images