Effectiveness of COL-1492, a nonoxynol-9 vaginal gel, on HIV-1 transmission in female sex workers: a randomised controlled trial.
BACKGROUND
Nonoxynol-9 (rINN, nonoxinol-9) is an over-the-counter spermicide that has in-vitro anti-HIV-1 activity. Results of studies of its effectiveness in prevention of HIV-1 infection in women have been inconclusive. We aimed to assess effectiveness of this vaginal gel.


METHODS
We did a randomised, placebo-controlled, triple-blinded, phase 2/3 trial with COL-1492, a nonoxynol-9 vaginal gel, in 892 female sex workers in four countries: Benin, Côte d'Ivoire, South Africa, and Thailand. 449 women were randomly allocated nonoxynol-9 and 443 placebo. Primary endpoint was incident HIV-1 infection. Secondary endpoints included Neisseria gonorrhoeae and Chlamydia trachomatis infections. Analysis was by intention to treat.


RESULTS
765 women were included in the primary analysis. HIV-1 frequency in nonoxynol-9 users was 59 (16%) of 376 compared with 45 (12%) [corrected] of 389 in placebo users (402.5 vs 435.0 woman-years; hazard ratio adjusted for centre 1.5; 95% CI 1.0-2.2; p=0.047). 239 (32%) women reported use of a mean of more than 3.5 applicators per working day, and in these women, risk of HIV-1 infection in nonoxynol-9 users was almost twice that in placebo users (hazard ratio 1.8; 95% CI 1.0-3.2). 516 (68%) women used the gel less frequently than 3.5 times a day, and in these, risk did not differ between the two treatments. No significant effect of nonoxynol-9 on N gonorrhoeae (1.2; 0.9-1.6) or C trachomatis (1.2; 0.8-1.6) infections was reported.


CONCLUSIONS
This study did not show a protective effect of COL-1492 on HIV-1 transmission in high-risk women. Multiple use of nonoxynol-9 could cause toxic effects enhancing HIV-1 infection. This drug can no longer be deemed a potential HIV-1-prevention method. Assessment of other microbicides should continue.
Van Damme
Lut
L
Institute of Tropical Medicine, Antwerp, Belgium. lvandamme@conrad.org
Ramjee
Gita
G
Alary
Michel
M
Vuylsteke
Bea
B
Chandeying
Verapol
V
Rees
Helen
H
Sirivongrangson
Pachara
P
Mukenge-Tshibaka
Léonard
L
Ettiègne-Traoré
Virginie
V
Uaheowitchai
Charn
C
Karim
Salim S Abdool
SS
Mâsse
Benoît
B
Perriëns
Jos
J
Laga
Marie
M
D000328:Adult; D002692:Chlamydia trachomatis / Q000187:drug effects; D005260:Female; D005782:Gels; D015658:HIV Infections / Q000635:transmission*; D015497:HIV-1; D006801:Humans; D008297:Male; D009344:Neisseria gonorrhoeae / Q000187:drug effects; D017137:Nonoxynol / Q000008:administration & dosage*; D011477:Sex Work; D013089:Spermatocidal Agents / Q000008:administration & dosage*
D005782:Gels; D013089:Spermatocidal Agents; D017137:Nonoxynol