Three out of four water-based sexual lubricants sold over the counter contain the chemical nonoxynol-9 (N-9), and more than one-third of men in the Vaccine Preparedness Study reported that they chose to use sexual lubricants containing (N-9). N-9 has been shown to be safe for vaginal use, and is the active ingredient in most vaginal contraceptive foams, creams, jellies and sponges. In the test tube, N-9 kills HIV, but its effects on the skin lining the rectum (the rectal mucosa) are not known. To find out whether N-9 is safe for use in the rectum, this study was designed to assess the safety of a cream that contains N-9 and that is known to be safe when used vaginally. Since the product, Advantage 24, comes in a single-use applicator, this study also gave us information about how gay men feel about using applicators to insert this product before anal sex.

35 low-risk, monogamous couples (25 couples in which both partners are HIV-negative and 10 in which both partners are HIV-positive) participated in this study.

WHAT HIVNET SITES WERE INVOLVED IN THE STUDY?

University of Washington, Seattle

Couples used Advantage 24 at increasing frequencies over an eight-week period. The men applied Advantage 24 daily, and planned to use it for anal intercourse at least three times per week during the study. The participants were counseled to use condoms for all episodes of anal intercourse. All participants received a free, unlimited supply of condoms and water soluble lubricants that do not contain N-9. Study participants recorded their use of Advantage 24, their sexual activity, and any health symptoms in daily diaries. The participants completed interviews and questionnaires on their experience using Advantage 24.

Men who applied the product rectally underwent periodic, frequent rectal exams to assess the effect of Advantage 24 on anal and rectal tissue. Men who applied the product to the penis received genital exams and urine testing to see if Advantage 24 caused any irritation or inflammation of the tissue of the penis and urethra.

Enrollment began in September 1996, and all participants completed the study in May 1997. The final laboratory work has been completed. A manuscript is in preparation.