Research eyes use of OTC disposable diaphragm’
The manufacturer of a feminine hygiene product is exploring potential use of the device as a disposable diaphragm and carrier for a microbicidal gel to deliver protection against pregnancy and sexually transmitted infections (STIs), including AIDS and HIV.
Instead, San Diego has received approval from the Moscow-based Russian Academy of Medical Sciences to market its Instead Softcup as an over-the-counter disposable contraceptive diaphragm in the Russian Federation. The company and the academy are launching clinical trials to test the efficacy of the Instead Softcup and its patented microbicidal and spermicidal gel Amphora.
"The Russian research will first address the efficacy of the Softcup/Amphora combination as a contraceptive, before moving on to proving its STI prevention capabilities," states Mary Frost, president of Instead. "The first round of testing is expected to involve hundreds of thousands of women at three clinical sites in Russia and should be under way this fall; the clinical testing for STI prevention should begin by the second quarter of 2004."
The Instead Softcup is a physical barrier-type intravaginal device made from a nonabsorbent, nonlatex material, which is a blend of polyethylene and synthetic plastics. It was launched in 1997 as a feminine hygiene product following FDA approval. It is sold in retail grocery stores and drug outlets in the United States and Canada, as well as on the company’s web site, www.softcup.com.
Does the company plan to pursue research of contraceptive use of the Instead device in the United States? Yes, says Frost, and if the device receives regulatory approval as a disposable diaphragm, it will be the first such product that can be sold over the counter, she says.
"Instead expects to complete its research on spermicide compatibility by the end of August and intends to file a pre-market notification with the U.S. Food and Drug Administration (FDA) by early October," reports Frost. "The research, which is being conducted by an independent testing laboratory, is part of an ongoing testing program that stretches back into the early 1990s that was designed to show how the Softcup could be used as both a feminine hygiene device and as a drug delivery device."
The company also is moving ahead to launch Amphora as a personal lubricant in the United States, states Frost. The company expects to have Amphora in distribution by the end of January 2004 and will be pricing the product at $5.99 for a 3 oz. package, says Frost.
Look at the device
According to the product web site, the device can be safely worn as a feminine hygiene product for up to 12 hours. When removed, it can be discarded in the trash, similar to tampons and panty liners.
The product directions instruct a woman to insert the Softcup into her vagina and slide the device under the cervix and behind the pubic bone. Women who use an intrauterine device (IUD) are advised by the product literature not to use the Softcup, as there is a risk of dislodging or removing the IUD by pulling on the IUD string while removing the Softcup.
Gel focus of research
Scientists may recognize Amphora as Acidform, an acid-buffering vaginal gel. Instead signed an agreement in February 2003 with Chicago-based Rush-Presbyterian-St. Luke’s Medical Center for an exclusive worldwide license to the microbicide, which was developed by Rush’s Program for the Topical Prevention of Conception and Disease.
To understand the microbicidal capabilities of Amphora, it is important to know that many STD-causing microbes, including HIV, as well as spermatozoa are inactivated at a pH less than 5.0, explains Lourens Zaneveld, DVM, PhD, emeritus professor of obstetrics and gynecology at Rush University, Rush-Presbyterian-St. Luke’s Medical Center in Chicago.
The pH of vaginal fluid ranges from 3.5 to 5.0 and is inclined to be protective against pathogenic microbes and immobilize spermatozoa; however, semen has a pH of 7.2 to 8.0 and has "quite good" buffering activity, he says. When semen enters the vagina, the pH rises to above 6.0, which allows spermatozoa and STD-causing microbes to survive. The pH of the vagina also rises to above 6.0 in the case of bacterial vaginosis (BV), which can put women at risk of infection from HIV and other STDs, says Zaneveld.
"The goal of our research was to develop a formulation with strong acid-buffering properties that can decrease the pH of semen to less than 5.0 and also acidify the vagina when the woman has bacterial vaginosis," he explains. "Amphora accomplishes this goal."
To study the acid-buffering, bioadhesive, viscosity-retaining, and spermicidal properties of Amphora, in vitro tests were performed.1 The study findings indicated Amphora brings the pH of semen down to below 5.0 even in the presence of threefold excess semen, states Zaneveld.
A Phase I study indicates that Amphora is safe, he says. Women who participated in the study recorded no complaints when the product was applied vaginally for six consecutive days, and no vaginal or cervical irritation was noted on visual or colposcopic inspection.2 Further testing will be needed to confirm the results of the early studies.
One of the problems with presently marketed contraceptive formulations is that many of them don’t adhere well to the vaginal wall; some may remain in the vagina only for 30 minutes, says Zaneveld. Intercourse may further hasten the elimination of these products, he notes.
Amphora incorporates a bioadhesive component that causes adhesion of the gel to the surface of the vagina and cervix so that it cannot be easily removed, he observes.
"Such long-lasting presence not only will provide long-term protection but will also allow the gel to be inserted well before intended intercourse, greatly increasing the spontaneity of the sex act," Zaneveld states.
References
1. Garg S, Anderson RA, Chany CJ II, et al. Properties of a new acid-buffering bioadhesive vaginal formulation (ACIDFORM). Contraception 2001; 64:67-75.
2. Amaral E, Faundes A, Zaneveld L, et al. Study of the vaginal tolerance to Acidform, an acid-buffering, bioadhesive gel. Contraception 1999; 60:361-366.
The manufacturer of a feminine hygiene product is exploring potential use of the device as a disposable diaphragm and carrier for a microbicidal gel to deliver protection against pregnancy and sexually transmitted infections (STIs), including AIDS and HIV.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
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