Nonhormonal options eyed for contraception
Enrollment for a 3,200-subject Phase III registration study has been completed for Amphora, a non-hormonal contraceptive gel. The three-year trial compares Amphora to Conceptrol, a nonoxynol-9 gel.
- Amphora is an acid-buffering gel that inactivates sperm, preventing conception.
- The Bill & Melinda Gates Foundation will announce winners later this fall for its challenge, "Develop the Next Generation of Condom." More than 500 applications have been submitted. The Foundation is looking for a next-generation condom that "significantly preserves or enhances pleasure, in order to improve uptake and regular use."
The next patient in your exam room is looking for a contraceptive method that is non-hormonal and can be used on a on-demand basis. What is your next move?
Spermicidal products, while offering less contraceptive protection than other methods, give women an option that is female-controlled, nonhormonal, and noninvasive. While commonly marketed for use with a diaphragm, they can be used alone for birth control. They rank in the lowest tier of contraceptive effectiveness, with 18 or more pregnancies per 100 women in one year with typical use.1According to Contraceptive Technology, 28% of women will experience an unintended pregnancy during the first year of typical use of spermicides; with perfect use, the number decreases to 18%.1
The active chemical agent in current products is nonoxynol-9 (N-9), a surfactant that destroys the sperm cell membrane. Spermicide concentration in U.S. products ranges from 8-12.5% in foam and from 2% to 4% in gels and creams.2Frequent use of spermicides containing N-9 has been associated with disruption of the genital epithelium, which might be associated with an increased risk for HIV transmission.3
Women in the United States might have another option in spermicides. Enrollment for a 3,200-subject Phase III registration study has been completed for Amphora, a non-hormonal contraceptive gel. The three-year trial compares Amphora to Conceptrol, the only N-9 spermicidal gel approved by the Food and Drug Administration (FDA). The Amphora trial began in April 2011 and will be completed in 2014, says Sean Edwards, president of Evofem, a San Diego-based biotechnology firm in charge of developing the potential product. Thirty-eight clinical sites participated in the trial.
Take a closer look
Amphora is an acid-buffering product that inactivates sperm, preventing conception. In early testing, Amphora showed promise as a contraceptive gel through its ability to immobilize sperm and to prevent certain sexually transmitted infections (STIs), including gonococci, herpes, chlamydia, HPV, and HIV.4-7However, it has not been tested for efficacy in preventing STIs. (Contraceptive Technology Update reported on Amphora. See "Potential spermicide enters advanced trial," June 2011, p. 63.)
Originally developed by the Topical Prevention of Conception and Disease Program at RushPresbyterian-St. Luke’s Medical Center, Chicago, Amphora was licensed to Evofem’s former company, Instead, in 2002, with patent protection granted in March 2004. Shortly thereafter, Amphora was granted FDA clearance for use as a personal lubricant; however, it has not been commercially marketed as such in the United States, states Edwards.
Clinicians will need to analyze the data for Amphora to finally quantify failure rates and discontinuation rates, observes Anita Nelson, MD, professor in the Obstetrics and Gynecology Department at the David Geffen School of Medicine at the University of California in Los Angeles. "Interestingly, spermicides may be used to bridge patients to more effective methods, so high, long-term discontinuation rates may not be as critical as they might be for longer-acting methods," she observes.
New condom designs eyed
Could clinicians see a new condom come their way? The Bill & Melinda Gates Foundation will announce winners later this fall for the 11th round of its Grand Challenges Explorations, which includes "Develop the Next Generation of Condom." More than 500 applications have been submitted, say foundation officials.
According to the foundation, it is looking for a next-generation condom that "significantly preserves or enhances pleasure, in order to improve uptake and regular use." Attributes that increase ease-of-use for male and female condoms, such as better packaging or designs that are easier to properly apply, will be considered. In addition, attributes that address and overcome cultural barriers also are desired.
To be considered for the challenge, the foundation states proposals must have a testable hypothesis, include an associated plan for how the idea would be tested or validated, and yield interpretable and unambiguous data in Phase I testing, in order to be considered for Phase II funding.
Male latex condoms, when used consistently and correctly, can reduce the risk of pregnancy and many STIs, including HIV.8They are inexpensive, available without a prescription, and easy to use.
The one major drawback to more universal use of male condoms is the lack of perceived incentive for consistent use, states foundation material for the condom challenge. Males might perceive condoms as decreasing pleasure as compared to no condom, creating a trade-off that many men find unacceptable, the foundation notes. Officials look to the challenge to see if it is feasible to develop a product without this stigma, or even better, is perceived to enhance pleasure.
REFERENCES
- Trussell J, Guthrie KA. Choosing a contraceptive: efficacy, safety, and personal considerations. In: Hatcher RA, Trussell J, Nelson AL, et al. Contraceptive Technology: 20th revised edition. New York: Ardent Media; 2011.
- Cates W, Harwood B. Vaginal barriers and spermicides In: Hatcher RA, Trussell J, Nelson AL, et al. Contraceptive Technology: 20th revised edition. New York: Ardent Media; 2011.
- Wilkinson D, Tholandi M, Ramjee G, et al. Nonoxynol-9 spermicide for prevention of vaginally acquired HIV and other sexually transmitted infections: systematic review and meta-analysis of randomised controlled trials including more than 5000 women. Lancet Infect Dis 2002; 2:613-617.
- Garg S, Anderson RA, Chany CJ 2nd, et al. Properties of a new acid-buffering bioadhesive vaginal formulation (ACIDFORM). Contraception 2001; 64:67-75.
- Spencer SE, Valentin-Bon IE, Whaley K, et al. Inhibition of Neisseria gonorrhoeae genital tract infection by leading-candidate topical microbicides in a mouse model. J Infect Dis 2004; 189:410-419.
- Tuyama AC, Cheshenko N, Carlucci MJ, et al. ACIDFORM inactivates herpes simplex virus and prevents genital herpes in a mouse model: optimal candidate for microbicide combinations. J Infect Dis 2006; 194:795-803.
- Herold BC, Kirkpatrick R, Marcellino D, et al. Bile salts: natural detergents for the prevention of sexually transmitted diseases. Antimicrob Agents Chemother 1999; 43:745-751.
- Warner L, Steiner MJ. Male condoms. In: Hatcher RA, Trussell J, Nelson AL, et al. Contraceptive Technology: 20th revised edition. New York: Ardent Media; 2011.
