Sept. 30, 2002 Frequent use of nonoxynol-9 potentiates transmission of
HIV-1 but not of gonorrhea or chlamydia, according to results of a randomized
trial reported in the Sept. 28 issue of The Lancet.
Although laboratory studies have suggested that this common spermicide gel might
help prevent HIV-1 infection, this trial suggests that it is not only ineffective,
but could actually increase HIV-1 transmission if used more than three times daily.
The investigators and editorialist stress the importance of developing an effective
"Nonoxynol-9 no longer has a part to play in HIV-1-prevention," lead author Lut
Van Damme, MD, formerly from the Institute of Tropical Medicine in Antwerp, Belgium
and now with CONRAD in Arlington, Virginia, says in a news release. "Our data
show that low frequency use of nonoxynol-9 causes neither harm nor benefit; but
that frequent use increases a woman's risk of HIV-1 infection by causing lesions."
This placebo-controlled, triple-blinded trial analyzed data from 765 female sex
workers in South Africa, Côte d'Ivoire, Benin, and Thailand. Incidence of
HIV-1 infection was 16% (59 of 376) in women who used nonoxynol-9 and 27% (104
of 389) in users of placebo gel (402.5 vs. 435.0 woman-years; hazard ratio [HR]
adjusted for center 1.5; 95% confidence interval [CI] 1.0-2.2; P=.047).
In 239 women (32%) who used more than 3.5 applicators per working day, risk of
HIV-1 infection in the nonoxynol-9 group was almost twice that in placebo users
(HR 1.8; 95% CI 1.0-3.2), which the authors attributed to toxic effects of the
spermicide causing vaginal lesions with epithelial disruption. In women who used
the gel less frequently, infection rates were similar in the nonoxynol-9 and placebo
"It is vitally important that the global effort to develop an effective vaginal
microbicide that reduces the risk of acquisition of HIV (and preferably other
sexually acquired infections) among women does not lose any momentum as a result
of the negative results of the van Damme trial," David Wilkinson, from the University
of South Australia in Adelaide, writes in an accompanying commentary. "The concept
is sound, the need is great, and many important lessons have been learned: the
Reviewed by Gary D. Vogin, MD Laurie Barclay, MD, is a staff writer with WebMD.