Unexpected Inflammatory Effects of Intravaginal Gels (Universal Placebo Gel and Nonoxynol-9) on the Upper Female Reproductive Tract: an Experimental Crossover Study

Intravaginal HIV microbicides could provide women with a self-controlled means for HIV prevention, but results from clinical trials have been largely disappointing. We postulated that unrecognized effects of intravaginal gels on the upper female reproductive tract (FRT) might contribute to the lower-than-expected efficacy of HIV microbicides. In this observational crossover study, 28 healthy female volunteers used no product (control cycle) or used a nightly application of intravaginal nonoxynol-9 gel [N9] as a 'failed' microbicide or the universal placebo gel [UPG] as a 'safe' gel, from the end of menses to the mid-luteal phase (intervention cycles). They then underwent sample collection for measurements of T-cell phenotypes, transcriptional profiling, and protein levels from 3 anatomic sites above the vagina: the cervical transformation zone, the endocervix and the endometrium. We used hierarchical statistical models to estimate mean (95% CI) intervention:control fold-changes in relevant phenotype levels. Exposure to N9 and UPG generated a common 'harm signature' that included transcriptional up-regulation of inflammatory genes CCL20 and IL8 in the cervix, decreased protein concentrations of secretory leukocyte protease inhibitor and increased percentages of terminally differentiated CD4+ effector T-cells in the endocervix, and transcriptional up-regulation of inflammatory mediators KIR3DS1, glycodelin-A, and osteopontin in the endometrium. These results underscore the need to consider the effects of microbicide agents and gel excipients on the upper FRT in studies of vaginal microbicides. Given the pro-inflammatory effects of UPG on the upper FRT, it may not be a suitable placebo for microbicide trials.

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Smith-McCune K, Chen JC, Greenblatt RM, Shanmugasundaram U, Shacklett BL, Hilton JF, Johnson B, Irwin JC, Giudice LC