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New Frontiers in Contraceptive Research: A Blueprint for Action (2004)

Chapter: Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development

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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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Suggested Citation:"Appendix A: Examples of Progress and Impediments in Contraceptive Research and Development." Institute of Medicine. 2004. New Frontiers in Contraceptive Research: A Blueprint for Action. Washington, DC: The National Academies Press. doi: 10.17226/10905.
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APPENDIX A Examples of Progress and Impecliments in Contraceptive Research and Development This appendix provides an update on some of the targets identified as promising in the 1996 IOM report (Institute of Medicine, 1996) and describes what progress has been made and what impediments still exist. It is not meant to be comprehensive but rather is meant to highlight examples of some of the changes that have taken place since 1996. Specifi- cally, updates on microbicide development, male contraceptives, anti- progestins, and immunocontraception are provided. Table A.1 lists a variety of reversible female contraceptives that have been approved since 1996 or that are currently under development. All of the contraceptives listed are essentially variations of previous methods that have been avail- able for as long 20 to 40 years. Thus far, no truly novel targets that could provide completely new approaches to contraception have advanced to the clinical testing stage. ADVANCES IN MICROBICIDES AND SPERMICIDES The worldwide HIV/AIDS epidemic has spurred a great deal of activity in the area of vaginal microbicide development. Microbicides entail a wide variety of formulations that include chemicals, antibodies, or buffers that can prevent the transmission of sexually transmitted infec- tions (STIs) and in many cases that also act as spermicidal contraceptives. Several microbicides are already in clinical trials to test their efficacy in preventing pregnancy and STI transmission, but many others are also at earlier stages of development. Examples of microbicides in development are listed in Table A.2. 163

64 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH TABLE A.1 Female Contraceptives: Changes Since 1996 Contraceptive Type and Use Effectiveness Mechanism of Action Rate and Description Develops Reversible, FDA approved Mirena Levonorgestrel- ~ 99% in the LNG renders the endometrium Approves releasing first year. unresponsive to estrogen, up to5 y' intrauterine Similar in which is responsible for growth of use in: system form to a of uterine lining in preparation Develope (LNG IUS). T-shaped for pregnancy. LNG also manufact IUD. renders the cervical mucus Distribute Vertical hostile to sperm penetration, Laboratory portion hence preventing fertilization. developir of T bears a small cylinder containing LNG. NuvaRing Hormone/ 98%-99% The first monthly hormone- Developed monthly when used releasing vaginal ring used for FDA on ( vaginal ring. as directed. birth control. A soft, flexible transparent ring A/ inch thick with an outer diameter of 2 inches containing etonorgestrel and ethinyl estradiol. Impedes ovulation and implantation. Unlike Cervical caps and diaphragms, the exact placement in the vagina is not critical for it to be effective. The ring is left in the vagina for 3 weeks, after which it is removed for 1 week and then a new ring is inserted. Progesterone Hormone/ Over 98.5% Inhibits cervical mucus Approver vaginal ring vaginal ring. when used production and prevents as directed. ovulation in lactating women. Lunelle Hormone/ 99% Combines medoxyprogesterone Approves monthly acetate and estradiol cypionate, Manufact injection. which suppress ovulation, the comp thicken the cervical mucus, October 2 and thin the endometrium. because c Intramuscular injections are potency a given by a health care provider failure. every 28 to 30 days.

APPENDIX A 165 Development and FDA Approval Side Effects Atrium on, ~ growth Oration cus ration, cation. one- sed for xible Inch thick of 2 inches '1 and les lion. d Placement .cal for it is left in after 1 week nserted. romen. esterone pionate, In, us, am. ~ are Provider Approved by FDA in December 2000 for up to 5 years of use. Approved for 5 years of use in most countries where it is available. Developed by Population Council and manufactured by Schering Oy Laboratories. Distributed in the United States by Berlex Laboratories. Widely used in Europe and developing countries. Developed by Organon, Inc. Approved by FDA on October 3, 2001. Approved only in Chile. Approved by FDA in October 2001. Manufactured by Pharmacia Corporation; the company initiated a voluntary recall October 2002 of Lunelle prebilled syringes because of a lack of assurance of full potency and possible risk of contraceptive failure. Irregular bleeding and amenorrhea, rare hormone-related side effects. Health benefits include reduced number of days of bleeding and increase in hemoglobin levels. Irregular bleeding, weight gain, breast tenderness, nausea, changes in mood. Minimal. Same as those for combination oral hormonal contraceptives. continued

166 TABLE A.1 Continued NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Effectiveness Mechanism of Action Contraceptive Type and Use Rate and Description Develops Implanon Hormone/ 99% Implanon is a progestogen-only FDA app: implant. contraceptive implant; a small, Organon flexible rod, 40 millimeters (mm) long and 2 mm in diameter inserted under the skin on the inside of the upper arm. Contains 68 mg of etonorgestrel released over the 3-year life of the device. Inhibits ovulation and thickens the cervical mucus. Norplant Hormone/ 97-99% Six thin, flexible silicone capsules, Received implant. 33 mm long and 2.4 mm in no longer diameter, containing 36 mg of because ~ LNG, for a total of 216 ma. U.S. mark The capsules are inserted under in 58 cow the skin in a minor surgical Council. procedure; this method is effective for up to 5 years. Jadelle Hormone/ 99% implant. Two flexible silicone rods filled with LNG inserted under the skin (very similar to Norplant). Each Jadelle rod is 43 mm long and 2.5 mm in diameter and contains 5 mg of LNG (total of 150 mg); effective for up to 5 years. Received approved However United St Populatic by Scheri Ortho Evra Transdermal 99.6% when A transdermal patch is applied Received hormonal used as each week for 3 weeks and is November system. directed. then removed for 1 week. Produced It uses ethinyl estradiol and norelgestromin. Depo-Provera Hormone 97-99% when An intramuscular injection of Received injection. used as depo-medroxyprogesterone produced directed. acetate given every 12 weeks. Seasonale Hormonal oral Over99% Used for 84 days before a 7-day Develope contraceptive when used placebo instead of the usual Received as directed. 21-day/7-day cycle. It contains LNG and ethinyl estradiol.

APPENDIX A 167 Development and FDA Approval Side Effects ,en-only small, hers (mm) eter on the rgestrel ~ life of ration ~1 mucus. ~ capsules, I in mg of fig. id under ,ical iS rs. ds filled er the skin ate. Each fig and ~ contains 50 mg); rs. applied and is ok. and ion of tone reeks. a 7-day Usual ontains dol. FDA approved and marketed by Organon International since 1998. Received FDA approval in 1990 but is no longer available in the United States because Wyeth Ayerst took it off the U.S. market. Norplant has been approved in 58 countries. Developed by Population Council. Received FDA approval in 1996; presently approved for use for up to 5 years. However, it is not yet available in the United States. Developed by the Population Council and manufactured by Schering Oy Received FDA approval on November 20, 2001. Produced by Ortho-McNeil. Received FDA approval in 1992, produced by Pfizer. Developed by Barr Laboratories, Inc. Received FDA approved in September 2003. Irregular bleeding, weight gain, acne, headache, and breast tenderness. Irregular bleeding, headache, weight gain, nausea, and acne. Irregular bleeding, weight gain, headaches, acne, and mood changes. Same as those for combination oral hormonal contraceptives. Amenorrhea. Same as those for combination oral hormonal contraceptives. continued

168 TABLE A.1 Continued NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Contraceptive Type and Use Effectiveness Mechanism of Action Rate and Description Develops Cyclessa Hormonal oral contraceptive Over 99% Desogestrel/ethinyl estradiol. when used as directed. ~ 93% over 1 year of typical use. Received Decembe Develope Yasmin Hormonal oral Over99% Yasmin is amonophasic birth Received contraceptive when used controlpill. Each of the first Develope as directed. 21 pills contains the same amount Yasmin 2 ~93% over of estrogen (ethinyl estradiol) on May 2 1 year of and progestin (drospirenone). Develope typical use. LNG Hormonal oral Reduces the Believed to act as an EC FDA app (Levonorgestrel) contraceptive risk of principally by preventing following Known as Plan B pregnancy ovulation or fertilization; it may the only ~ when used for from ~ 8% also inhibit implantation, but is Develope emergency to 1.1% not effective once implantation (WCC) fit contraception following a has begun. Itis administered other not (EC). single act of within 72 hours of unprotected submitter unprotected intercourse for EC as two use to FD sex. consecutive doses (12 hours research' apart) of 0.75 mg of LNG, a research ~ totally synthetic progestogen Health In (total dose of 1.5 mg). of Califor Children' Pittsburg: (WHO). E of intent i from the LNG and Emergency oral Combined LNG and ethinylestradiol. Received ethinyl contraceptive EC is 75% Develope estradiol tablets effective. Preven Emergency oral 74% effective LNG and ethinyl estradiol. FDA app: Emergency contraceptive (wish no The PREVEN Emergency Develope Contraceptive contraception, Contraceptive regimen uses Kit 7.2% the Yuzpe method. Therapy pregnancies must be initiated as soon as expected; possible within 72 hours after with Yuzpe unprotected intercourse. method, 1.9% pregnancies expected.)

APPENDIX A 169 Development and FDA Approval Side Effects radial. c birth first be amount adiol) none). g a; it may n, but is unction ,tered Protected 10 ours G. a togen dol. uses rapy In as s after Received FDA approval on December 20, 2000. Developed by Organon, Inc. Received FDA approval in May 2003. Developed by Berlex Laboratories. Yasmin 28 was approved by the FDA on May 2001, and earlier in Europe. Developed by Schering AG. FDA approved Plan B in July 1999 for EC following unprotected sex and is currently the only progestin-only EC approved by FDA. Developed by Women's Capital Corporation (WCC) financed largely by foundations and other not-for-profit organizations. WCC submitted an application for nonprescription use to FDA on April 21, 2003; supporting research was conducted by not-for-profit research organizations, including Family Health International (FHI), the University of California at San Francisco, the Children's Hospitals of Los Angeles and Pittsburgh, and the World Health Organization (WHO). Barr Laboratories, Inc., signed a letter of intent in October 2003 to acquire Plan B from the WCC. Received FDA approval on April 29, 2003. Developed by Barr Laboratories, Inc. FDA approved as of June, 1999. Developed by Gynetics, Inc. Same as those for combination oral hormonal contraceptives. Same as those for combination oral hormonal contraceptives, except for less bloating than that with other hormonal methods. Produces much less vomiting and nausea than other ECs containing both progestin and estrogen. Vomiting and nausea are potential side effects of EC pills. Vomiting and nausea are potential side effects of EC pills. continued

170 TABLE A.1 Continued NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Effectiveness Mechanism of Action Contraceptive Type and Use Rate and Description Develops Leah's Shield Vaginal barrier ~ 85% over One size, reusable vaginal barrier Develope used with a 1 year of use. method made of silicone with a March 14 spermicidal cup-shaped design and a valve, collabora lubricant. and loop for easy removal. and PHI. FemCap Vaginalbarrier. 77.2% over Silicone rubber cervical cap in FemCap, 1 year of use. three sizes with a brim designed March 28 to fit into the vaginal fornices. (EC Certi Available SILCS Vaginal barrier. Not tested A reusable vaginal barrier in Develope diaphragm yet. three sizes with a dome that Technolo, covers the cervix, a rim that fits with SIL( the vaginal fornices, and a brim being stun that conforms to the vagina. safety. Reality female Vaginal barrier. ~ 95% when Barrier. Made of plastic Collabora condom used as polyurethane (stronger then Medtech directed. latex). Today Sponge Vaginal barrier 89% to 91% The active ingredient in the FDA app when used Today Sponge is nonoxynol-9. Whitehal: according to another c instructions; currently otherwise use effectiveness rate is 84% to 87%.

APPENDIX A 17 Development and FDA Approval Side Effects Al barrier Developed at Yama Inc. Approved by FDA Minimal. e with a March 14, 2002. Studies have been conducted a valve, collaboratively between CONRAD, Yama, vat. and FHI. cap in FemCap, Inc., received FDA approval on Minimal. designed March 28, 2003. Approved in Europe rnices. (EC Certificate No. 99-010901~. Available in Germany and Italy. ier in Developed at Program for Appropriate Minimal. that Technology in Health (PATH) in conjunction that fits with SILCS, Inc. The SILCS device is currently ~ a brim being studied for function, acceptability, and Gina. safety. than Collaboration between CONRAD and Minimal. Medtech Products Ltd. (in India). ~ the FDA application was withdrawn by Minimal. ynol-9. Whitehall-Robins Healthcare and then filed by another company; Allendale Pharmaceuticals; currently under review by FDA. continued

172 TABLE A.1 Continued NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Contraceptive Type and Use Effectiveness Mechanism of Action Rate and Description Develops Examples of Reversible Contraceptives in Development Progesterone receptor modulators Biodegradable implants, for example, Capronor Hormonal oral Unknown contraceptive but estrogen-free H orm one - releasing implants GnRH analogs Could be administered subdermally or other ways. Nestorone/EE . . . vaginal rmg Antigonadotropic. Prevents follicular growth and suppresses ovulation. NA NA Female hormonal Phase II trials contraceptive, indicate over progestin and 90% ovulation estrogen. suppression. Implants containing progestin are implanted under the skin of the arm or hip. The hormone is released gradually into the body for 12 to 18 months. Capronor II consists of two rods of polyte-caprolactone), each containing 18 mg of levonorgestrel (LNG). Capronor III is a single capsule of copolymer (caprolactone and trimethylenecarbonate) filled with 32 mg of LNG. With both systems, the implant remains intact during the first year of use and thus could be removed if needed. Over the second year, it biodegrades to carbon dioxide and water, which are absorbed by the body. A new group of drugs known as GnRH antagonists can be used to prevent the release of FSH and LH from the pituitary gland. The release of FSH and LH triggers ovulation and spermatogenesis (the development of sperm). Blocking the release of these hormones temporarily suppresses fertility for women and men. Suppresses follicular growth and ovulation. In FDA p None has One form GnRH an Developed Phase II t formulati in Swede

APPENDIX A 173 Development and FDA Approval Side Effects ents Oppresses Breslin are in of the le is the body Donor II itch norgestrel single aprolactone rate) filled implant he first old be or the tdes to :er, which iy. known as be used to SH and land. The triggers Genesis army. these suppresses men. owth In FDA pipeline. None has been FDA approved. One form, Cetrorelix, is approved as a GnRH antagonist for other indications. Developed by the Population Council. Phase II trials completed, phase III trials formulation and manufacture by Q Pharma in Sweden. First-generation antagonists caused histamine release and local allergic reaction. New analogs are better tolerated. continued

174 TABLE A.1 Continued NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Effectiveness Mechanism of Action Contraceptive Type and Use Rate and Description Develops Frameless IUDs, IUD Same rate as Similar to regular IUDs but In Europe including other IUDs without the rigid frame. It is United K Gynefix (~99%~. hoped that they will cause less cramping because there is no rigid frame to press against the uterus. It consists of six copper tubing segments attached to a nylon thread, with a knot at the top end that serves as an anchor. The knot is implanted in the myometrium of the uterine fundus, permanently securing the device in the uterine cavity. Silicone plugs Reversible No A reversible, nonsurgicalmethod Studies a nonsurgical pregnancies of tubalsterilization. Liquid Used by method of tubal reported, silicone is injected into the sterilization, but 8% fallopian tubes. The silicone such as Ovabloc experienced hardens and blocks the tube with migration of a rubbery plug that can be the plugs. removed. Could also be used in males. Irreversible Essure Nonsurgical >99%with An expendable microcoilinsert Received sterilization vie successful placed in the fallopian tubes, Manufact bilateral placement; where it promotes the formation occlusion of the first of tissue that blocks the fallopian tubes procedure passageway and anchors the placement device permanently in place. rate of 86%. Insertion procedure does not require an incision in the abdominal cavity and can be performed under local anesthesia. Chemical Nonsurgical NA scarring sterilization Two different chemical combinations can be used to achieve scarring that eventually blocks the fallopian tubes: phenol (carbolic acid) with a thickening agent or phenol with quinacrine Quinacri~ by any re further te any forth

APPENDIX A 175 Development and FDA Approval Side Effects but . It is use less ~ is no rinst the copper id to a of at the n anchor. n the rme curing cavity. al method quid the cone tube with be ~ used in ail insert :ubes, ormation AS the ~lace. is not le en tee anesthesia. ed to entually es: phenol . . .1C. (enlng :inacrine In European clinical trials. Available in the United Kingdom since 1998. The frameless IUDs occasionally have problems with early expulsion, though Gynefix is said to have a lower rate of expulsion. Studies are under way in the Netherlands. Unknown. Used by men in China. Not FDA approved. Received FDA approval in September 2002. Manufactured by Conceptus. Quinacrine is used in China; not approved by any regulatory body; recommended to be further tested in studies with animals before any further use in humans. Discomfort on day of insertion. Cancer risk, potential damage to a fetus if inadvertently administered to a pregnant woman, and increased risk of ectopic pregnancy. continued

176 TABLE A.1 Continued NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Effectiveness Contraceptive Type and Use Rate Mechanism of Action and Description Develops Chemical plugs Nonsurgical NA sterilization. Cryosurgery Nonsurgical NA sterilization. Introduction of chemicals, such as methylcyanoacrylate (MCA), into the fallopian tubes. Liquid nitrogen is used to freeze the cornua; scar tissue blocks the fallopian tubes. Approves NOTE: NA = not available. GENERAL SOURCES: FHI (http: / /www.fhi.org/en/RH/Pubs/Network/vl8_1 /NW181ch5.htm) FDA (http: / /www.fda.gov/) U.S. Patent and Trademark Office (http://www.uspto.gov/) Planned Parenthood Federation of America (http://www.plannedparenthood.org/), especially (http://www.plannedparenthood.org/ARTICLES/bcfuture_w.html) Geneva Foundation for Medical Education and Research (http://www.gfmer.ch/) Reproductive Health Online, from Johns Hopkins University (http: / /www.reproline.jhu.edu/) Population Council, New York, NY (http://www.popcouncil.org/)

FEN ~ 177 Development and FDA Approval Side E~c~ ls, such (~CA), to Reese Coca Approved ~ Canada and the Nethedands. Trussed and Vaughn, lggg sit: Yasm~ (http: / /~.yasmin~om) Today Sponge (ht~: / /~iodaysponge~om/) Company sites: Barr Laboratories (http: / /~.barrl~s.com/home.ht~l) Progesterone king: ~assai et aL, 2000; diva et at lgg7 i.org/), haul) ah/)

78 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH TABLE A.2 Examples of Microbicides and Spermicides in Development Microbicide Type and Use Effectiveness Mechanism of Action Rate and Description Stage of I Examples of microbicides with spermicidal activity BufferGel Microbicide; Unknown; Maintains the natural acidity of Develope (Carbopol buffered gel. potential the vagina, even in the presence Johns Ho polymer) Nonirritating spermicide of seminal fluid, and creates a NICHD a lubricant made and physical barrier that inhibits the Network of a Carbopol gel protection passage of pathogens into the and side ~ (Carbopol 974P), against STIs. vaginal and cervical epithelium. United St which is a high- countries molecular- clinical tr weight, cross- and Unit linked phase II/ polyacrylic acid. activity a: It contains no oil anti-HIV or detergent and in 2006. is compatible for use with condoms and latex diaphragms. Savvy Microbicide; Unknown. Equimolar mixture of the In2002,~ (C31G) surfactant. amphoteric surfactants cetyl successfu Designed to be betaine and myristamine oxide; and office applied vaginally surfactant/detergent that kills or dose esca before sexual disables pathogens by stripping (PCT) stu intercourse. them of their outer covering. now posi It is also a for contrz spermicide. herpes si~ and gono Ushe rcell Microb icide gel; Unknown; High-mole cular-weight cellulose Develop e ' (cellulose adsorption in vitro and sulfate compound. Prevents (Canada) sulfate) inhibitor. animal pathogens from adhering to and Preventic studies have eventually passing through the (TOPCAL shown that walls of healthy cells. Ushercell Ushercell is clinical tr a potent tolerance contraceptive trials are and human cl. microbicide. year 2004

APPENDIX A ~opment 179 Stage of Development and FDA Approval Side Effects cidity of presence eates a tibias the tto the ~thelium. he cetyl re oxide; at kills or tripping ~ring. cellulose ents fig to and ugh the Developed by ReProtect LLC and Johns Hopkins University with support from NICHD and the HIV Prevention Trials Network (HPTN). Two clinical trials for safety and side effects with 27 women in the United States and 98 women in four other countries have been conducted. Two smaller clinical trials have shown BufferGel to be safe and nonirritating to men. Data from phase II/III trial on BufferGel's contraceptive activity are expected in 2004; data on the anti-HIV activity of BufferGel are expected in 2006. In 2002, with support from NICHD, Biosyn successfully completed two phase I/II safety and efficacy studies for C31G vaginal gel, a dose escalation study, and a postcoital testing (PCT) study for contraceptive efficacy. C31G is now positioned to enter phase III clinical trials for contraception and the prevention of HIV, herpes simplex virus, and chlamydia infections and gonorrhea. Developed by Polydex Pharmaceuticals (Canada) and the Program for the Topical Prevention of Conception and Disease (TOPCAD; Chicago, IL). As of September 2002, Ushercell has completed three phase I/II clinical trials of safety, acceptability, and male tolerance of 6% gel. Other phase I/II clinical trials are planned and ongoing. Phase III human clinical trials are planned for fiscal year 2004 under the direction of CONRAD. In a phase I trial, mild vaginal itching and irritation. Vaginal candidiasis and hyperkeratotic lesions required discontinuation of the product in a small percentage of trial participants. An international phase I clinical trial had similar results. Adverse events were categorized as mild to moderate, and included Candida on wet mount, vaginal/vulva! itching or burning after insertion or when passing urine, labial rash, lower abdominal pain, and vaginal discharge. continued

180 TABLE A.2 Continued NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Effectiveness Mechanism of Action Microbicide Type and Use Rate and Description Stage of I ACIDFORM Microbicide; Unknown; Has no active ingredient but is a Instead It buffered gel. potential combination of compounds that Center (T Designed to be spermicide work together to maintain the phase I sc applied vaginally and natural protective acidity of the the Globe before sexual protection normalvaginalenvironment, acceptabi intercourse. against even in the presence of alkaline is planner STIs. semen. Maintains low vaginal pH, which immobilizes sperm and should prevent multiplication and survival of sexually transmitted pathogens. Praneem Spermicide. Unknown. Mechanismis unknown or Phase Itr Contains purified uncharacterized. and Repr extracts from the neem tree combined with citrate oil. Examples of microbicides with no known spermicidal activity Carraguard Microbicide in Assumed Fusion inhibitor; it provides a Develope (formerly aqueous solution; to be non- physical barrier that keeps HIV funding f known as adsorption contraceptive and other pathogens from Foundati. PC-515) inhibitor. on the basis reaching target cells. Carragua Designed to be of laboratory based mi. applied vaginally work. effectiven before sexual intercourse. Emmelle Microbicide gel; Not known A phase I trial of safety with Develope (dextrin sulfate) adsorption to be males has been completed. United K inhibitor. effective as a Phase I and II trials of safety and by the M' Icodextrin-based contraceptive. dosage have been completed. United K intravaginal gel Phase III clinical trial to be Medicine to prevent HIV conducted in Africa is being infection. planned (M-L Laboratories). Lactin vaginal Microbicide. Unknown. Recolonizes the vagina with Phase IIt capsule Lactobacillus to maintain vaginal sponsored acidity.

APPENDIX A 18 Stage of Development and FDA Approval it but is a Ends that sin the ty of the meet, alkaline aginal sperm ival of thogens. Or rides a ups HIV m with :ed. afety and valeted. Be being ries). with ~ vaginal Instead Inc. licensed from Rush Medical Center (TOPCAD) in February 2003. Two phase I safety studies were completed by the Global Microbicide Project (GMP); an acceptability trial for use with diaphragm is planned for 2004. Phase I trials at the Institute of Research Unknown. and Reproduction, India Developed by the Population Council, with funding from CDC, USAID, and the Gates Foundation. Several phase I and II trials of Carraguard and earlier forms of carrageenan- based microbicides were completed; phase III effectiveness trials will begin in January 2004. Developer: M-L Laboratories in the United Kingdom. Phase II trials supported by the Medical Research Council, United Kingdom, Institute of Tropical Medicine, Belgium Phase II trials at the University of Pittsburgh sponsored by NIAID No side effects mentioned. Phase II trials have shown Carraguard to be safe when taken vaginally for up to 12 months. continued

182 TABLE A.2 Continued NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Effectiveness Mechanism of Action Microbicide Type and Use Rate and Description Stage of I Polystyrene Microbicide gel; Unknown. A phase l sulfonate adsorption expanded inhibitor. Sponsored Designed to be applied vaginally before sexual intercourse. PRO2000 Microbicide gel; Unknown; Unlike other sulfonated polymers, Clinicalb (naphthalene adsorption potential such as dextransulfate,which act Indevus I 2-sulfonate inhibitor. efficacy by birding to the V3 loop of conducted polymer) Designed to tee demonstrated glycoprotein gpl20, PRO2000 welltoler applied vaginally in rabbits. also binds to CD4 cells and women. I before sexual interferes with the gpl20-CD4 conducted intercourse. interaction. It provides a physical Africa, in barrier that keeps HIV and other profile in pathogens from reaching the PRO 200C target cells. large pha and prott women it several A SAMMA Microbicide gel; Unknown. In vitro tests found that Preclinica (mandelic acid adsorption mandelic acid condensation St. Luke'` condensation inhibitor. polymer inhibits sperm function polymer) Designed to be (but does not kill sperm). applied vaginally before sexual intercourse. Tenofovir Microbicide gel. Non- Non-nucleoside reverse PMPA gel spermicidal. transcriptase inhibitor; interferes with transcription of viral RNA to DNA. SOURCES: http: / /www.itg.be/micro2002/downloads/presentations/2Monday_May_13_2002/ Track_B_C_session / Polly_Harrison.p df http: / /www.aegis.com/news/bw/2003/BW030206.html http: / /www.aidsmap.com/web /pbl /eng/EF5AB676-885A4F55-8912-9DDlFE9BEE92.htm http: / /www.mihivnews.com/microbicides-news.htm http: / /www.agi-usa.org/pubs/journals/grO40501.html

APPENDIX A 183 Stage of Development and FDA Approval Side Effects A phase I safety study has been completed; expanded safety studies are planned. Sponsored by GMP. polymers, which act up of ~ 2000 and 'O-CD4 a physical and other fig the lotion function interferes rat RNA Clinical trials undertaken by NIH, HPTN, and Indevus Pharmaceuticals. Phase I clinical trials, conducted in Europe, found that PRO 2000 was well tolerated by healthy, sexually abstinent women. Findings from a phase I/II trial, conducted in the United States and South Africa, indicate a similarly promising safety profile in healthy, sexually active women. PRO 2000 has been selected for testing in a large phase II/III pivotal trial to assess safety and protective efficacy. This trial will involve women in the United States, India, and several African countries. Preclinical studies at Rush-Presbyterian- Unknown. St. Luke's Medical Center, Chicago. A few non-HIV-positive male patients reported mild symptoms of genital itching, tingling, irritation, dryness, discoloration, or flaking of the dried gel. Unknown. http: / /www.niaid.nih.gov/daids/prevention/text/microbes.htm http: / /www.global-campaign.org/clientfiles/PipelineFactsheet.pdf http: / /www.global-campaign.org/clientfiles/cone.pdf http: / /www.rhtp.org/micro/micro_research_pipeline.htm http: / /www.popcouncil.org/biomed/microbicides.html Amaral et al., 1999; Garg et al., 2001

84 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH The development of an effective contraceptive microbicide presents an enormous challenge in that it must be highly effective against patho- gens and sperm, but it must not disrupt the normal flora or mucosal cells of the vagina even when it is used very frequently. In addition, establish- ing evidence of efficacy requires multiple clinical trials with different populations to test both the efficacy of the microbicide as a contraceptive and the efficacy of the microbicide for protection against specific STIs. Thus, the clinical testing stage is a very expensive, time-consuming pro- cess. To complicate matters, the Food and Drug Administration (FDA) has not provided guidance on how best to test the safety and efficacy of microbicides in clinical trials. At a recent meeting of an FDA advisory panel, the group discussed whether tests of microbicides should compare the product to condom use or to an inactive placebo, or both. The group also discussed how long an experimental microbicide trial should be and what data would need to be reported to show that the microbicide was effective. However, the panel was unable to come to a consensus on the issues and noted that the first experimental microbicide to be tested would likely face many obstacles (Kaisernetwork, 2003~. Recently, the field has been energized by an influx of new funding from nonfederal and federal sources and by the establishment of several new initiatives or organizations. For example, the Global Microbicide Project (Global Microbicide Project, 2000~ was established in 2000 to help develop new microbicidal agents that specifically address the needs and perspectives of women. The main objective of this project is to develop vaginal methods that would protect women against STIs including HIV/ AIDS. Funding for GMP comes solely from the Bill and Melinda Gates Foundation to expedite microbicide development. Additional funding to investigate the contraceptive efficacy of microbicides is available through the Consortium for Industrial Collaboration in Contraceptive Research (CICCR). GMP can provide funds for both pilot and major projects. Although there is no requirement for cost sharing by an industrial part- ner, it is strongly encouraged. There is no limit to funding for a project, but initial funding for a new project may be limited in time and amount until the feasibility of the proposed approach has been determined. Recently, the U.S. Agency for International Development has also provided signifi- cant sums of money to the Population Council, Family Health Inter- national, and CONRAD (the parent organization of GMP and CICCR) for microbicide development. Support from other foundations may also speed progress in the field. The International Partnership for Microbicides (International Partnership iSee http://www.gmp.org/ (accessed September 2003~.

APPENDIX A 185 for Microbicides, 2002) was established in 2002 as a result of a study sup- ported by the Rockefeller Foundation. IPM acts as a coordinating body and central repository of funds, with the goal of accelerating progress in the microbicide field. The formation of the Alliance for Microbicide Development has been credited with driving progress in the field as well. Founded in 1998, the Alliance2 is a global, not-for-profit organization whose sole mission is to speed the development of safe, effective, and affordable microbicides to prevent STIs, most critically, HIV/AIDS. The Alliance defines itself as a catalyst, communicator, convener, and problem solver. It consists of a global coalition of representatives from more than 200 biopharmaceutical companies, not-for-profit research institutions, and health advocacy groups. As such, it provides authoritative information on microbicide devel- opment, facilitates dialogue on key policy issues, provides education about the public health potential of microbicides, and serves as an advo- cate for the resources needed to develop them. The work of the Alliance is funded by contributions from the William and Flora Hewlett Foundation, the International Partnership for Microbicides, the Moriah Fund, the Rockefeller Foundation, the Bill and Melinda Gates Foundation through GMP, and a number of private contributors. Other areas of contraceptive research would likely also benefit from the establishment of similar entities that could serve as information sources and activity coordinators. UPDATE ON MALE CONTRACEPTION Hormonal Methods Before the 1960s, when oral contraceptives and intrauterine devices (IUDs) were introduced, the most commonly used contraception methods- condoms and withdrawal were male directed. Even now, contraceptive use among men, which is essentially limited to condoms and vasectomy, accounts for nearly one-third of all current contraceptive use in the United States and worldwide (Meriggiola et al., 2003~. Surveys performed in recent years also suggest that the majority of men are willing to share the responsibility for family planning and that women in stable relationships would trust their male partner to use contraceptives (Glacier et al., 2000; Martin et al., 2000; Weston et al., 2002~. The potential for hormonal contraception for men has been recognized for more than 50 years, and a number of regimens have been tested in the clinic, but to date, none has been submitted for FDA review or approved 2http: / /www.microbicide.org/ (accessed August 2003~.

86 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH for use in other countries. (See Table A.3 for examples of male contracep- tives in development.) Significant efforts have been devoted to the devel- opment of male hormonal contraceptives over the last several decades. However, progress has been quite slow for a variety of reasons, including sporadic funding, limited interest by pharmaceutical companies, and at times, political and cultural concerns (Meriggiola et al., 2003; reviewed by Waites, 2003~. An additional impediment may be the lack of regulatory guidelines on the requirement for demonstrating the safety and efficacy of male contraceptives (Nieschlag et al., 2002~. Nonetheless, the World Health Organization (WHO) and CONRAD have been major forces in moving the field forward. A number of male-directed methods are in clini- cal trials, and at least one (testosterone undecanoate [TU]) appears to be close to achieving registration for use in China (Waites, 2003~. Several others (Table A.3) are at earlier stages of development but show signifi- cant promise (Meriggiola et al., 2003; Waites, 2003~. Reversibility is the primary attraction of hormonal methods. Approxi- mately 3,000 men have participated in clinical trials of male hormonal contraceptive methods over the last 20 years, and none of them has failed to return their sperm counts to normal and eventual fertility.3 One limita- tion of such methods is the slow onset and offset of action from 1 to 4 months because of the hormones' delayed effects on spermatogenesis in the testes. A further incentive for development is the theoretical possibility that some of these agents could eventually decrease the risk of some diseases, such as prostate disease. They might also possibly result in a decreasing rate of baldness, which, although not a health issue, might be important in terms of acceptance. Long-term effects on health, however, are unknown. The three formulations currently used in the development of male hormonal contraceptives are testosterone alone, testosterone plus progestins, and testosterone plus gonadotropin-releasing hormone (GnRH) antago- nists. All of these agents exploit the same basic mechanism. They inhibit the central stimulatory pathways for gonadotropin production, which leads to the suppression of Leydig cell function and testosterone secretion and, thus, to decreased sperm production in the testes. Exogenous testoster- one replaces the suppressed endogenous testosterone, which is necessary to maintain libido and well-being. The administration of testosterone alone can produce azoospermia in some men, but this approach has been plagued by considerable variabil- ity in response. For example, in an early WHO study of couples, only 65 3William J. Bremner, University of Washington, in a presentation at the International Sym- posium on New Frontiers in Contraceptive Research, Washington, DC, July 15-16, 2003.

APPENDIX A 187 percent of the participating men developed azoospermia (World Health Organization Task Force on Methods for the Regulation of Male Fertility, 1990~. There was, however, a very low birth rate in the group because the majority of men experienced oligospermia (abnormally low sperm counts). A later WHO trial documented a total failure rate for testosterone of about 3 to 4 percent (World Health Organization Task Force on Methods for the Regulation of Male Fertility, 1996), which is comparable to the failure rates that are often reported for female methods. This failure rate is vastly better than that reported for the condoms, which would be the appropriate direct comparison for these methods. High-dose testosterone had some side effects, such as increased muscle mass and weight, with a corresponding decrease in fat mass, but these were not viewed as adverse events. Some participants experienced an increase in oily skin and acne, and there was also about a 10 percent decrease in high-density lipoprotein (HDL) levels.4 About 25 percent of the men experienced a decrease in testicular size as well. Other traditional androgens are also being tested as single-agent contraceptives. TU has been available as an oral preparation for decades and has been used, primarily by the Chinese, in oil as an injectable prepa- ration. In a recent efficacy study in China, 299 of 308 men achieved either azoospermia or had counts low enough to enter an efficacy phase of the study (Gu et al., 2003~. There was only one pregnancy among couples who were using TU as the sole means of contraception for 1 year, and no serious side effects were reported. Researchers are also exploring whether the addition of progestins to testosterone can lead to a more effective contraceptive. Formulations have included depot medroxypro~esterone acetate (DMPA); levonor~estrel , ... .. . . . . ~ . . . . .. . . . . ... teltner orally or in implants); clesogesterol and its in VlVO metanollte, etonorgestrel (in an implant made by Organon); and cyproterone acetate (CPA; which is taken orally). In one study, which compared testosterone alone to the same dose of testosterone enanthate combined with oral levonorgestrel, the progestin showed a clear additive effect on the rapidity and completeness of sup- pression of sperm production compared with the effect of testosterone alone (Bebb et al., 1996~. In a study of CPA plus testosterone compared with testosterone alone, the progestin again increased the rapidity and completeness of suppression of sperm production, and at higher doses all men achieved azoospermia (Meriggiola et al., 1996~. Testosterone has also been combined with GnRH antagonists. GnRH fit is not known whether this has the same risk that is associated with spontaneous low HDL levels.

88 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH TABLE A.3 Examples of Male Contraceptives in Development Effectiveness Mechanism of Action Contraceptive Type and Use Rate and Description Stage of I Cystatin 11 Epididymal protein. Depo- Hormonal No pregnancy Long-acting progestin, medroxy- suppression in55 couples Antigonadotropic agent,blocks progesterone of sperm treated with LH and FSH production and acetate production. DMPA + hence sperm production. (DMPA) Used in testosterone combination pellets every with some 3 to 4 months. form of testosterone replacement. Studies ~ Eppin Immuno- Unknown. Stimulates immune system to Promisin contraceptive. inactivate an epididymal enzyme that plays a role in sperm maturation. GnRH coupled Immuno- Unknown. Stimulates immune system to In early s with protein contraceptive. inactivate the body's natural GnRH, suppressing sperm production. Lonidamine Male (LND) nonhormonal derivatives contraceptive. Unknown. Understanding is incomplete; causes premature release of germ cells from the testis by action on the adherers junctions between Sertoli and germ cells. Approves Populatic analogs t] nontoxic low doses pending. MENT (7-oc- Synthetic Nine of 11 Antigonadotropic and androgen In the ED methyl-l9- hormone men in a replacement. Populatic nortestosterone) resembling dosage trial testosterone; had zero implanted sperm counts under the after four skin of a implants. man's upper arm (a transdermal gel is used in aging males).

APPENDIX A 189 Stage of Development and FDA Approval Side Effects Studies with primates are planned. t, blocks ~ and tem to ~1 enzyme m tem to natural rm replete; ,e of germ action on between ~ndrogen Androgen deficiency (requiring that testosterone pellets are also used); delay of up to 7 months before recovery of spermatogenesis. Promising results from studies with primates. Unknown. In early stages of research. Approved for use as an anticancer drug. Population Council developed two synthetic analogs that are antispermatogenetic and nontoxic in rats. Results of tests of toxicity at low doses over long periods of time are pending. In the FDA pipeline. Developed by the Population Council and Schering AG Unknown. No effect on the prostate. continued

190 TABLE A.3 Continued NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Effectiveness Mechanism of Action Contraceptive Type and Use Rate and Description Stage of I Testosterone Male 68% Suppresses GnRH secretion and buciclate (TB) hormonal responded. thus sperm production. contraceptive; androgen. Injected every 3 months. Testosterone Male Suppresses GnRH secretion and One of th enanthate (TE) hormonal thus sperm production. hypogon' contraceptive; hormone] androgen. Injected; potent for 10 days. Testosterone Male Suppresses GnRH secretion and Efficacy s undecanoate hormonal thus sperm production. (TU) contraceptive; androgen. Vasclip Vasectomy 97.5% Polymeric clip occludes Approves alternative; vas deferens to prevent Now avai should be sperm flow. Expected considered permanent. Reversible Vas deferens Reported to SMA complex is injected into the Phase I al inhibition of occlusion by be 100% vase deferentia by a no-scalpel Currently sperm under styrene when procedure. The positive and guidance maleic correctly negative charge mosaic causes (RISUG) anhydride inserted in the membranes of passing (SMA) vas deferens, sperm to rupture. complexed in small with the studies. solvent dimethyl sulfoxide. SOURCES: Cheng et al. (2001), Gatto et al. (2002), Gupta (2003), Mishra et al. (2003), World Health Organization Task Force on Methods for the Regulation of Male Fertility (1990) http: / /www.popcouncil.org/biomed/malecontras.html http: / /www.reproline.jhu.edu/ http: / / www. engenderhealth. org / wh / fp / ceff.html#barrier

APPENDIX A 191 Stage of Development and FDA Approval Side Effects lion and lion and lion and d into the -scalpel and causes ng Oily skin, aggressiveness, increased muscle mass, decreased HDL levels. One of the earliest treatments for hypogonadism, researched as a male hormonal contraceptive since the 1970s. Efficacy study in China. Approved by FDA in August 2002. Now available in the United States. Expected launch in Europe by January 2004. Phase I and phase II trials completed in India. Currently in phase III clinical trials. Similar to those of other androgens. Similar to those of other androgens. Pain during procedure, although significantly reduced pain and complications compared with those after a traditional vasectomy. Because RISUG does not completely block the flow of sperm through the vas deferens, it appears not to have any of the negative side effects associated with vasectomies. Lack of toxicity remains to be confirmed. http: / /www.reproline.jhu.edu/english/6read/6issues/6network/vl8-3/ntl835a.html http: / /www.avert.org/condoms.htm#2 http: / /www.popcouncil.org/publications/popbriefs/pb8~2~_4.html http: / /www.malecontraceptives.org/methods/risug.htm

92 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH antagonists block the effect of GnRH coming from the hypothalamus to the pituitary gland and thereby decrease the production of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which reduces the levels of testosterone and sperm production. This approach has been shown in small pilot studies in the United States and Europe to be an effective method, although it has not been determined how long this sup- pression can be maintained, and larger follow-up studies are needed (Swerdloff et al., 1998~. To avoid undesirable side effects, GnRH antago- nists cannot be used in isolation. Testosterone is a necessary adjunct for the long-term use of such antagonists. This combination can be used to achieve azoospermia in a variety of ways, but one approach is to use a GnRH antagonist like acyline for a brief period such as 12 weeks at the initiation of a regimen to help with suppression of sperm production and then to stop the antagonist and use testosterone enanthate alone. Nonhormonal Methods Various orally active nonhormonal agents have been found in animal models to interfere with spermatogenesis without reducing testosterone levels. Lonidamine is a nonsteroidal, nonhormonal antispermatogenic agent that acts by premature exfoliation of germ cells from the seminiferous epithelium (De Martino et al., 1981; Silvestrini et al., 1984~. Although this was a novel mode of action, lonidamine was not developed as a male contraceptive because of its toxic effects on the liver and kidney, but it was used as an antitumor agent (Silvestrini, 1991; Silvestrini et al., 1984~. More recently, analogs of lonidamine were discovered that appeared to have the same action on the testes, but apparently without the toxicity of lonidamine (Cheng et al., 2001, 2002; Grima et al., 2001~. The Population Council, with the assistance of CICCR, the Mellon Foundation, and the National Institute of Child Health and Human Development (NICHD), has been working on the lead analog AF2364. Certain hexahyrdoindenopyridines have been reported to act as reversible male contraceptive agents (Cook et al., 1997~. A 28-day toxicity study with rats did not reveal any significant toxicity but did confirm the male contraceptive effect (Fail et al., 2000~. CICCR is discussing with the Research Triangle Institute the possibility of supporting some further studies with one of the lead compounds in this series, and it is hoped that collaboration with a pharmaceutical company will be possible. Lastly, a recent report has described the contraceptive activity of alky- lated imino sugars in male mice (van der Spoel et al., 2002~. When the lead compound, N-butyldeoxynojirimycin, was given orally, epididymal sperm had abnormal head shapes and lacked acrosomal antigens. The motility of the affected spermatozoa was abnormal, and the mice became

APPENDIX A 193 infertile after 3 weeks of dosing. Fertility was regained in the fourth week after dosing ceased. This compound appeared to exert its effect through interference with the biosynthesis of glucosylceramide-based sphingo- lipids. These investigators are planning to develop this lead compound further. These are examples of exciting new contraceptive agents already at the proof-of-concept stage and merit further support as potential sec- ond-generation nonhormonal male contraceptives. UPDATE ON ANTIPROGESTINS AS FEMALE HORMONAL CONTRACEPTIVES The first antiprogestin was discovered in 1980. Since then, more than 400 compounds with antiprogestin activities have been synthesized (Hodgen, 1991), but only a handful have been tested with humans, includ- ing mifepristone (formerly Roussel-Uclaf, now Exelgene), onapristone and lilopristone (Schering AG), Org 31710 and Org 31806 (Organon, Inc.), and CDB 2914 (developed by NICHD). Antiprogestins can affect reproductive function because they bind to progesterone receptors in the hypothalamus, anterior pituitary, and uterus; and in doing so, they inhibit transcription of the genes that are normally activated by progesterone. In other words, the antiprogestins act as receptor antagonists. The contraceptive effects of antiprogestins depend on the dose and the time of the ovarian cycle at which they are administered. Various regimens of mifepristone have been tested, includ- ing a single postcoital dose for emergency contraception, as well as daily, weekly, and monthly regimens for conventional contraception (reviewed by Glasier, 2002~. The theoretical advantages of weekly or monthly re- gimes include exposure to lower total doses of the drug, but a disadvan- tage may be the difficulty in remembering to take the drug at the appro- priate time. In each case, inhibition of ovulation or significant disruption of endometrial development, or both, is thought to contribute to contra- ceptive efficacy. The contraceptive effects of mifepristone have been demonstrated most clearly in trials of emergency contraception. A single dose of 10, 50, or 600 milligrams (mg) of mifepristone each appears to be equally effec- tive in preventing pregnancy, even up to 120 hours after intercourse (Task Force on Postovulatory Methods of Fertility Regulation, 1999~. The mode of action of mifepristone when it is used as an emergency contraceptive depends on the stage of the menstrual cycle when it is taken. Given before ovulation, it prevents ovulation from occurring. Given after ovulation, the effect on the endometrium is indicative of impaired implantation. For the daily regimen, doses of mifepristone from 10 mg down to 0.1 mg have been tested. Doses between 2 and 10 mg daily have all been

94 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH shown to inhibit ovulation (Brown et al., 2002; Cameron et al., 1995; Croxatto et al., 1993; Ledger et al., 1992~. Sixty-five percent of women taking 2 mg/day and 88 percent of those taking 5 mg/day experienced amenorrhea. Although follicular activity continued during treatment, endometrial development was altered by doses ranging from 0.5 to 10 ma, suggesting that even if ovulation did occur, implantation would have been very unlikely. The contraceptive efficacy of daily low-dose mifepristone has been demonstrated in only two studies. In a study from Scotland and China (with 5 mg of mifepristone), 50 women used no other method of contraception and there were no pregnancies (Brown et al., 2002~. In a study of 32 women using 0.5 mg of mifepristone daily, 16 women com- pleted 6 months of use. In 141 cycles, there were five pregnancies (Marions et al., 1999~. In tests of mifepristone administered once per week, doses of 10 to 50 mg were associated with variable inhibition of ovulation (Chen and Xiao, 1997; Spitz et al., 1996), whereas doses of 5 and 2.5 mg did not inhibit ovulation (Gemzell-Danielsson et al., 1996~. However, all doses affected endometrial development. The efficacy of a weekly regimen has been tested in only one study involving 18 women (Marions et al., 1998~. In that study, three pregnancies occurred over 63 cycles. The administration of mifepristone once per month is thought to pre- vent pregnancy by inhibiting implantation. A number of studies have demonstrated that 200 mg of mifepristone given in the early luteal phase slows endometrial development without altering the timing of the next menses. Two studies have demonstrated greater than 95 percent contra- ceptive efficacy of 200 mg of mifepristone given within 2 days of the LH surge (Gemzell-Danielsson et al., 1993; Hapangama et al., 2001~. The lim- iting factor to this approach is the accurate detection of the LH surge, as the timing of mifepristone administration is critical. A few other antiprogestins have been tested in studies with humans as well, but much less extensively than mifepristone. Onapristone and lilopristone (Schering AG, Berlin) were both tested for their potential effects on reproductive function in humans, but onapristone was aban- doned after phase I studies demonstrated changes in liver function, and lilopristone has not been taken forward. Organon has published data on two antiprogestins, Org 31710 and Org 31806 (Kloosterboer et al., 1994), but clinical testing has not progressed past a very early stage. CDB 2914, which is structurally and functionally similar to mifepristone, has been shown to have no adverse effects in normally cycling women at doses of up to 200 mg (Passaro et al., 1997; Stratton et al., 2000~. A clinical trial of this compound as an emergency contraceptive has been completed and results are undergoing analysis. A new group of compounds called mesoprogestins has also been syn-

APPENDIX A 195 thesized and characterized by lenapharm GmbH & Co. (lena, Germany). These compounds bind strongly to the progesterone receptor but have mixed agonistic and antagonistic activities in viva (Chwalisz et al., 2000~. Their antiproliferative effects on the endometrium are being investigated in studies with animal models, including primates, but no studies with humans have yet been published. Although antiprogestins have significant potential for contraceptive development, progress has been hindered by the political controversy surrounding mifepristone, which is licensed in many parts of the world as an abortifacient for use during early pregnancy. Lobbying efforts by groups opposed to abortion have led to limited interest and activity in the development of contraceptive antiprogestins by both the pharmaceutical industry and not-for-profit organizations, despite their potential for pre- venting unplanned pregnancy. UPDATE ON IMMUNOCONTRACEPTION The development of contraceptive vaccines has been pursued since the early days of contraceptive research, but progress in this field has been exceedingly slow, and the work has yet to produce a vaccine that is proven safe and effective for use in humans. Although various investigators had immunized animals with reproductive antigens since the early 1960s, the field of immunocontraception for humans was really launched as a result of a special consultation convened by WHO in Boston in 1973. This was followed by a symposium, Immunological Approaches to Fertility Control, the seventh in the series of Karolinska Symposia on Research Methods in Reproductive Endocrinology (1974~. Exploratory studies funded by WHO were undertaken to assess the feasibility of such an approach. WHO then held a symposium in Varna, Bulgaria, in 1975. Papers dealing with different potential antigens, including sperm, eggs, and hormones of the trophoblast, were presented and published (1975~. Consideration was also given to the safety of such approaches. Three main considerations that are critical to the success of such an immunological approach are the length of time that antibodies will be effective, the reversibility of the immuno- contraceptive, and the hypothetical potential for teratogenicity during periods when antibody levels are declining. At the time, there was great enthusiasm for a vaccine approach, which was novel and different from available contraceptive approaches, and WHO was supporting the work of about 30 scientists. Use of the ~ chain of human chorionic gonadotropin (phCG) was con- sidered to be the most promising lead at the time. Use of the whole phCG subunit to immunize female baboons showed that antibodies were pro- duced and pregnancy was prevented. A group in India pursued the use of

96 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH the whole ~ chain conjugated to tetanus toxoid. After appropriate safety tests, this preparation was administered to women, and it was found that when the circulating antibody was above a threshold value, women were protected from pregnancy; but some women did not respond, and charac- teristics that would predict a lack of response could not be identified be- forehand. This threw into question the practicality of a method in which antibody levels would have to be assessed at regular intervals. Another disadvantage of this approach was that antibodies were also raised against the ~ subunit of LH (pLH), and from a long-term perspective this was believed to be unsafe. WHO therefore concentrated on only small pieces of the phCG protein that were not present in pLH, but ensuring a good antibody response to these small peptides has proved difficult. In the intervening years, the WHO Task Force on Immunological Approaches to Fertility Control continued to support work in this field, but because of unsatisfactory results and declining funding, most leads were abandoned; the phCG approach was not, however. Delays occurred because of difficulties in selection of adjuvants5 and delivery vehicles that did not cause local reactions. Nonetheless, an application was submitted to the regulatory authorities in Sweden in May 2002 to carry out a phase I clinical trial with the current formulation of the phCG immunocontra- ceptive. A manufacturer of the immunocontraceptive that meets Good Manufacturing Practice standards has been identified, and preparation of clinical supplies of the formulation awaits funding. Lack of funding has also delayed the planned safety studies to be run concurrently with the phase I trial. The anti-hCG approach still appears to be the most practical because of several very attractive features. First, hCG has a clearly defined biologi- cal function that depends on its secretion into the maternal circulation, where it is readily accessible to antibodies. Circulating antibodies can act on the circulating hormone, and one does not have to be concerned with raising adequate antibody levels in an organ such as the fallopian tube or the uterus, which would be the case with many other potential antigens. High levels of pregnancy prevention have been observed in baboons and women if titers are high enough. The trial in India demonstrated that an antibody titer of 50 nanograms per milliliter (ng/ml) was effective in preventing pregnancy. The antibody response declined with time, and fertility was regained when titers fell below 35 ng/ml (Talwar et al., 1994~. Second, there is evidence from a study carried out in many developed countries that showed that women wanted a long-acting method that was 5A substance that is added to a vaccine to improve the immune response so that less vaccine is needed to produce more antibodies.

APPENDIX A 197 not permanent but that could be taken without the knowledge of others, especially if it did not cause any endocrine or other metabolic distur- bances, had no overt signs of being used, and did not need storage or disposal. An hCG immunocontraceptive meets all of these criteria, which is not true of most other methods. Given the past results, it is likely that booster vaccinations would be needed every 2 to 3 months to maintain adequate antibody responses, but it is known from use of hormonal injectable contraception in women that even monthly injections can be acceptable in some settings (Snow et al., 1997~. The production of inex- pensive, home-use diagnostic kits would circumvent the problems of assessing antibody levels in cases where the actual titer was critical for contraception by allowing women to determine when the titer is too low to be effective. Such a kit could also screen out the nonresponders. Third, if reversibility became an issue in a small percentage of women, adminis- tration of exogenous progesterone to maintain the pregnancy is a potential solution. However, despite the promise and potential, the project is still at the early clinical trial stage some 30 years after work on this concept began. Some might question whether the work on phCG should be terminated, since the immunocontraceptive has not reached fruition in 30 years. On the other hand, 20 years of research and substantially greater funding have been devoted to the development of an anti-HIV vaccine, without success to date. The case for continued work on immunocontraceptives has recently been cogently put forth by Aitken (2002~. New funding sources, perhaps developed through grass-roots lobbying from consumers wanting differ- ent options, could potentially spur progress of the immunocontraceptive approach. The Alliance for Microbicide Development could serve as an instructive model in that regard. Other targets and formulations for contraceptive vaccines are also under investigation, but thus far, proof of concept has not been firmly established (reviewed by Gupta, 2003~. Because immunocontraception could provide an alternative and novel method of fertility regulation, funding should be made available to establish proofs of concept for the most advanced and promising leads, based on sound science, to move the field forward. Examples include sperm surface antigens and epididymal carbohydrate antigens, as well as antigens known to induce immune responses in infertile couples (see the section on proteomics in Chapter 2 for more detail). In the ovum, the oolemma (vitelline membrane) might also be a viable target, although little is known about the oolemma, and such research would be at a much earlier stage than the stages of the approaches noted above. One challenge for these alternate approaches is accurate assessment of the immune status of those vaccinated. If antibodies are raised to inhibit

98 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH circulating hormones such as hCG, measurement of the antibody levels is meaningful, but when the level of antibody needs to be high in the fallo- pian tube, uterus, or even epididymis, the validity of such measurements is questionable. Experiments with one sperm antigen, sperm-specific LDH-C4, with baboons (both male and female), in which some protection against pregnancy was achieved, there was no relationship between cir- culating antibody levels and fertility status (Mahony et al., 2000; O'Hern et al., 1995~. In addition, a similar lack of correlation between antibody levels and fertility status has been seen in macaque monkeys (Tollner et al., 2002~. In ongoing trials of sperm antigen vaccines, antibody levels will be measured in the female reproductive tract secretions, followed by fer- tility studies with monkeys after active immunization (primary injection with two boosts). Some have also raised ethical considerations about contraceptive vac- cines. For example, an anti-hCG vaccine would block the establishment of pregnancy after fertilization, and thus is viewed unfavorably by some as an abortifacient rather than a contraceptive. In addition, following the Indian clinical trial, some women's groups expressed concern that this method could be used to sterilize women without their knowledge or that it could be administered along with routine vaccinations without their knowledge. It is imperative that consumers be involved in the continuing development of such immunocontraceptives to provide knowledge and reassurance. Good science alone is not enough to ensure uptake of such a method. Creative introduction strategies will be critical to ensure the widespread acceptance of such new contraceptive methods once an effec- tive and safe vaccine is obtained. The lack of funding for translational research to move promising leads from proof of concept to a product is a major impediment, but the lack of papers on immunocontraception at annual meetings of major scientific societies also indicates a waning interest in the field. A helpful means of reenergizing the field would be the establishment of an annual immuno- contraceptive workshop, modeled after the ovarian or testis workshops. NICHD could play a leading role in the organization and funding of such an undertaking. REFERENCES Aitken RJ. 2002. Immunocontraceptive vaccines for human use. J Reprod Immunol 57~1- 2):273-287. Amaral E, Faundes A, Zaneveld L, Wailer D, Garg S. 1999. Study of the vaginal tolerance to Acidform, an acid-buffering, bioadhesive gel. Contraception 60~6~:361-366. Bebb RA, Anawalt ED, Christensen RB, Paulsen CA, Bremner WJ, Matsumoto AM. 1996. Combined administration of levonorgestrel and testosterone induces more rapid and effective suppression of spermatogenesis than testosterone alone: a promising male contraceptive approach. J Clin Endocrinol Metab 81~2~:757-762.

APPENDIX A 199 Brown A, Cheng L, Lin S. Baird DT. 2002. Daily low-dose mifepristone has contraceptive potential by suppressing ovulation and menstruation: a double-blind randomized con- trol trial of 2 and 5 mg per day for 120 days. J Clin Endocrinol Metab 87~1~:63-70. Cameron ST, Thong KJ, Baird DT.1995. Effect of daily low dose mifepristone on the ovarian cycle and on dynamics of follicle growth. Clin Endocrinol (Oxf) 43~4~:407-414. Chen X, Xiao B. 1997. Effect of once weekly administration of mifepristone on ovarian func- tion in normal women. Contraception 56~3~:175-180. Cheng CY, Silvestrini B. Grima J. Mo MY, Zhu LJ, Johansson E, Saso L, Leone MG, Palmery M, Mruk D. 2001. Two new male contraceptives exert their effects by depleting germ cells prematurely from the testis. Biol Reprod 65~2~:449-461. Cheng CY, Mo M, Grima J. Saso L, Tita B. Mruk D, Silvestrini B. 2002. Indazole carboxylic acids in male contraception. Contraception 65~4~:265-268. Chwalisz K, Brenner RM, Fuhrmann UU, Hess-Stumpp H. Elger W. 2000. Antiproliferative effects of progesterone antagonists and progesterone receptor modulators on the endometrium. Steroids 65~10-11~:741-751. Cook CE, Jump JM, Zhang P. Stephens JR, Lee YW, Fail PA, Anderson SA. 1997. Exception- ally potent antispermatogenic compounds from 8-halogenation of (4aRS,5SR,9bRS)- hexahydroindeno-[1,2-c]pyridines. J Med Chem 40~14~:2111-2112. Croxatto HB, Salvatierra AM, Croxatto HD, Fuentealba B. 1993. Effects of continuous treatment with low dose mifepristone throughout one menstrual cycle. Hum Reprod 8~2~:201-207. De Martino C, Malcorni W. Bellocci M, Floridi A, Marcante ML. 1981. Effects of AF 1312 TS and lonidamine on mammalian testis: a morphological study. Chemotherapy (Baser) 27 (suppl 2~:27-42. Fail PA, Anderson SA, Cook CE. 2000. 28-day toxicology test: indenopyridine RTI 4587-056 in male Sprague-Dawley rats. Reprod Toxicol 14~3~:265-274. Garg S. Anderson RA, Chany CJ II, Waller DP, Diao XH, Vermani K, Zaneveld LJ. 2001. Properties of a new acid-buffering bioadhesive vaginal formulation (ACIDFORM). Contraception 64~1~:67-75. Gatto MT, Tita B. Artico M, Saso L. 2002. Recent studies on lonidamine, the lead compound of the antispermatogenic indazol-carboxylic acids. Contraception 65~4~:277-278. Gemzell-Danielsson K, Swahn ML, Svalander P. Bygdeman M.1993. Early luteal phase treat- ment with mifepristone (RU 486) for fertility regulation. Hum Reprod 8~6~:870-873. Gemzell-Danielsson K, Westlund P. Johannisson E, Swahn ML, Bygdeman M, Seppala M. 1996. Effect of low weekly doses of mifepristone on ovarian function and endometrial development. Hum Reprod 11~2~:256-264. Glasier A. 2002. New developments in contraceptive drugs for use by women. Expert Opin Investig Drugs 11~9~:1239-1251. Glasier AF, Anakwe R. Everington D, Martin CW, van der Spuy Z. Cheng L, Ho PC, Anderson RA. 2000. Would women trust their partners to use a male pill? Hum Reprod 15~3~:646-649. Global Microbicide Project. 2000. Global Microbicide Project . . . Responding to an Urgent Need. [Online]. Available: http: / /www.gmp.org/ [accessed August 2003]. Grima J. Silvestrini B. Cheng CY.2001. Reversible inhibition of spermatogenesis in rats using a new male contraceptive, 1-~2,4-dichlorobenzyl)-indazole-3-carbohydrazide. Biol Reprod 64~5~:1500-1508. Gu YQ, Wang XH, Xu D, Peng L, Cheng LF, Huang MK, Huang ZJ, Zhang GY. 2003. A multicenter contraceptive efficacy study of injectable testosterone undecanoate in healthy Chinese men. J Clin Endocrinol Metab 88~2~:562-568. Gupta SK. 2003. Status of immunodiagnosis and immunocontraceptive vaccines in India. Adv Biochem Eng Biotechnol 85:181-214.

200 NEW FRONTIERS IN CONTRACEPTIVE RESEARCH Hapangama DK, Brown A, Glasier AF, Baird DT. 2001. Feasibility of administering mifepristone as a once a month contraceptive pill. Hum Reprod 16~6~:1145-1150. Hodgen GD. 1991. Antiprogestins: the political chemistry of RU486. Fertil Steril 56~3~:394- 395. Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Harrison PF, Rosenfield A, eds. Washington, DC: National Academy Press. International Partnership for Microbicides. 2002. About IPM. [Online]. Available: http:// www.ipm-microbicides.org [accessed August 2003]. Kaisernetwork. August 21,2003. Daily HIV/AIDS Report, Science ~ Medicine FDA Panel Meets to Discuss Ways to Test Safety, Efficacy of Experimental Microbicides to Prevent HIV Transmission. [Online]. Available: http://www.kaisernetwork.org/daily_reports/rep_ index.cfm?hint=l&DR_ID=19464 [accessed August 2003]. Karolinska Symposia on Research Methods in Reproductive Endocrinology. 1974. 7th Sym- posium, Immunological Approaches to Fertility Control. Diczfalusy E, ed. Stockholm, Sweden: Karolinska Institutet. Kloosterboer HI, Deckers GH, Schoonen WG.1994. Pharmacology of two new very selective antiprogestagens: Org 31710 and Org 31806. Hum Reprod 9(suppl 1~:47-52. Ledger WL, Sweeting VM, Hillier H. Baird DT. 1992. Inhibition of ovulation by low-dose mifepristone (RU 486~. Hum Reprod 7~7~:945-950. Mahony MC, Rice K, Goldberg E, Doncel G. 2000. Baboon spermatozoa-zone pellucida binding assay. Contraception 61~3~:235-240. Marions L, Danielsson KG, Swahn ML, Bygdeman M. 1998. Contraceptive efficacy of low doses of mifepristone. Fertil Steril 70~5~:813-816. Marions L, Viski S. Danielsson KG, Resch BA, Swahn ML, Bygdeman M, Kovacs L. 1999. Contraceptive efficacy of daily administration of 0.5 mg mifepristone. Hum Reprod 14~11~:2788-2790. Martin CW, Anderson RA, Cheng L, Ho PC, van der Spuy Z. Smith KB, Glasier AF, Everington D, Baird DT.2000. Potential impact of hormonal male contraception: cross- cultural implications for development of novel preparations. Hum Reprod 15~3~:637- 645. Massai R. Diaz S. Jackanicz T. Croxatto HB.2000. Vaginal rings for contraception in lactating women. Steroids 65~10-11~:703-707. Meriggiola MC, Bremner WJ, Paulsen CA, Valdiserri A, Incorvaia L, Motta R. Pavani A, Capelli M, Flamigni C.1996. A combined regimen of cyproterone acetate and testoster- one enanthate as a potentially highly effective male contraceptive. J Clin Endocrinol Metab 81~8~:3018-3023. Meriggiola MC, Farley TM, Mbizvo MT.2003. A review of androgen-progestin regimens for male contraception. J Androl 24~4~:466-483. Mishra PK, Manivannan B. Pathak N. Sriram S. Bhande SS, Panneerdoss S. Lohiya NK.2003. Status of spermatogenesis and sperm parameters in langur monkeys following long- term vas occlusion with styrene maleic anhydride. J Androl 24~4~:501-509. Nieschlag E, Anderson RA, Apter D.2002. Sixth Summit Meeting Consensus: recommenda- tions for regulatory approval for hormonal male contraception. Int J Androl 25~6~:375. O'Hern PA, Bambra CS, Isahakia M, Goldberg E. 1995. Reversible contraception in female baboons immunized with a synthetic epitope of sperm-specific lactate dehydrogenase. Biol Reprod 52~2~:331-339. Passaro M, Piquion J. Mullen N. Sutherland D, Alexander NJ, Nieman L. 1997. Safety and luteal phase effects of the antiprogestin CDB2914 in normally cycling women. In: Proceedings of the 79th meeting of the Endocrine Society. Minneapolis: p. 227. Silvestrini B. 1991. Lonidamine: an overview. Semin Oncol 18~2 suppl 4~:2-6. Silvestrini B. Palazzo G. De Gregorio M. 1984. Lonidamine and related compounds. Prog Med Chem 21:110-135.

APPENDIX A 201 Sivin I, Diaz S. Croxatto HE, Miranda P. Shaaban M, Sayed EH, Xiao B. Wu SC, Du M, Alvarez F. Brache V, Basnayake S. McCarthy T. Lacarra M, Mishell DR Jr, Koetsawang S. Stern J. Jackanicz T. 1997. Contraceptives for lactating women: a comparative trial of a progesterone-releasing vaginal ring and the copper T 380A IUD. Contraception 55(4):225-232. Snow RC, Guzman Garcia S. Kureshy N. Sadana R. Singh S. Becerra Valdivia M, Lancaster S. Hoffman M, Aitken I. 1997. Attributes of contraceptive technology: women's prefer- ences in seven countries. In: Sundari Ravindran TK, Berer M, Cottingham J. eds. Beyond Acceptability: Users' Perspectives on Contraception. London, UK: Reproductive Health Matters for the World Health Organization. Pp. 36-48. Spitz IM, Croxatto HB, Robbins A. 1996. Antiprogestins: mechanism of action and contra- ceptive potential. Annu Rev Pharmacol Toxicol 36:47-81. Stratton P. Hartog B. Hajizadeh N. Piquion J. Sutherland D, Merino M, Lee YJ, Nieman LK. 2000. A single mid-follicular dose of CDB-2914, a new antiprogestin, inhibits folliculogenesis and endometrial differentiation in normally cycling women. Hum Reprod 15~5~:1092-1099. Swerdloff RS, Bagatell CJ, Wang C, Anawalt BD, Berman N. Steiner B. Bremner WJ. 1998. Suppression of spermatogenesis in man induced by Nal-Glu gonadotropin releasing hormone antagonist and testosterone enanthate (TE) is maintained by TE alone. J Clin Endocrinol Metab 83~10~:3527-3533. Talwar GP, Singh O. Pal R. Chatterjee N. Sahai P. Dhall K, Kaur J. Das SK, Suri S. Buckshee K, et al. 1994. A vaccine that prevents pregnancy in women. Proc Natl Acad Sci U S A 91(18):8532-8536. Task Force on Postovulatory Methods of Fertility Regulation. 1999. Comparison of three single doses of mifepristone as emergency contraception: a randomised trial. Task Force on Postovulatory Methods of Fertility Regulation. Lancet 353~9154~:697-702. Tollner TL, Overstreet JW, Branciforte D, Primakoff PD. 2002. Immunization of female cynomolgus macaques with a synthetic epitope of sperm-specific lactate dehydrogenase results in high antibody titers but does not reduce fertility. Mol Reprod Dev 62~2~:257- 264. Trussell J. Vaughan B. 1999. Contraceptive failure, method-related discontinuation and resumption of use: results from the 1995 National Survey of Family Growth. Fam Plann Perspect 31~2~:64-72, 93. van der Spoel AC, Jeyakumar M, Butters TD, Charlton HM, Moore HD, Dwek RA, Platt FM. 2002. Reversible infertility in male mice after oral administration of alkylated imino sugars: a nonhormonal approach to male contraception. Proc Natl Acad Sci U S A 99(26):17173-17178. Waites GM. 2003. Development of methods of male contraception: impact of the World Health Organization Task Force. Fertil Steril 80~1~:1-15. Weston GC, Schlipalius ML, Bhuinneain MN, Vollenhoven BJ. 2002. Will Australian men use male hormonal contraception? A survey of a postpartum population. Med J Aust 176~5~:208-210. World Health Organization. 1975. Development of Vaccines for Fertility Regulation, WHO Sponsored Session of the Third International Symposium on Immunology of Reproduction, Varna. Copenhagen: Sciptor. World Health Organization Task Force on Methods for the Regulation of Male Fertility. 1990. Contraceptive efficacy of testosterone-induced azoospermia in normal men. Lancet 336~8721~:955-959. World Health Organization Task Force on Methods for the Regulation of Male Fertility. 1996. Contraceptive efficacy of testosterone-induced azoospermia and oligozoospermia in normal men. Fertil Steril 65~4~:821-829.

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More than a quarter of pregnancies worldwide are unintended. Between 1995 and 2000, nearly 700,000 women died and many more experienced illness, injury, and disability as a result of unintended pregnancy. Children born from unplanned conception are at greater risk of low birth weight, of being abused, and of not receiving sufficient resources for healthy development. A wider range of contraceptive options is needed to address the changing needs of the populations of the world across the reproductive life cycle, but this unmet need has not been a major priority of the research community and pharmaceutical industry. New Frontiers in Contraceptive Research: A Blueprint for Action, a new report from the Institute of Medicine of the National Academies, identifies priority areas for research to develop new contraceptives. The report highlights new technologies and approaches to biomedical research, including genomics and proteomics, which hold particular promise for developing new products. It also identifies impediments to drug development that must be addressed. Research sponsors, both public and private, will find topics of interest among the recommendations, which are diverse but interconnected and important for improving the range of contraceptive products, their efficacy, and their acceptability.

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