Colposcopically obtained images of vulvar, vaginal, and cervical epithelium for assessment of safety of intravaginal agents among normal adolescent females: comparison with in vivo exam and interobserver agreement

The evolving design and methods for trials evaluating the safety of candidate vaginal microbicides: a systematic review

Vaginal preexposure prophylaxis is a promising biomedical tool for HIV prevention. Although guidelines for the clinical assessment of microbicides are available, validated markers for product safety are lacking. To inform future microbicide and multipurpose vaginal product research, we reviewed the current and past safety methods used. We searched the Cochrane, EMBASE, and Ovid MEDLINE databases for clinical studies of vaginal products for the prevention of HIV that included safety evaluations. Ninety-seven clinical studies involving 21 products were identified: 63 lasted 14 days or less, 19 were longer in duration, and 15 were effectivess studies that included also safety as an outcome. Median sample size in the safety studies was 48 participants (range, 10-799). All studies reported on urogenital endpoint, 71% included colposcopy, and 67% assessed the vaginal microflora. Markers of vaginal epithelial inflammation, systemic absorption, and systemic toxicology assessments were evaluated in 29%, 26%, and 43% of studies, respectively. Excluding the effectiveness studies, these same assessments were done before 1998 in 33%, 7%, and 27% and after 2001 in 38%, 44%, and 60% of studies, respectively. Soluble inflammatory markers were introduced after 2001. Adverse event collection was reported in 73% of studies before 1998 and in 98% after 2001. In a previous review, we recommended that larger and longer safety studies were necessary to detect clinically important toxicities and to provide assurance that agents are ready for large-scale effectiveness trials. Here, we propose a stepwise clinical assessment that can be used for future guidance.

Optical coherence tomography compared with colposcopy for assessment of vaginal epithelial damage: a randomized controlled trial

OBJECTIVE

Colposcopy has been used to detect epithelial damage with vaginal microbicides. In animal models, optical coherence tomography provided increased sensitivity over colposcopy in detecting epithelial injury. This randomized, double-blinded, clinical study compared optical coherence tomography to colposcopy for the evaluation of epithelial injury in women using placebo or nonoxynol-9.

METHODS

Thirty women aged 18-45 were randomized to use hydroxyethyl cellulose placebo or nonoxynol-9 vaginal gel twice daily for 5.5 days. Imaging with colposcopy and optical coherence tomography was performed before product use, after the last dose, and 1 week later. Colposcopy was graded using standard criteria. Optical coherence tomography images were scored for epithelial integrity based on a published scoring system and were measured for epithelial thickness.

RESULTS

Colposcopy findings, optical coherence tomography scores, and epithelial thicknesses were similar between treatment groups at baseline. After treatment, there were significant differences between the nonoxynol-9 (1.37) and control group (1.15) optical coherence tomography scores (P<.001), indicating epithelial injury, and there was epithelial thinning in the nonoxynol-9 group (237 micrometers) compared with the control group (292 micrometers; P=.008). There were no significant posttreatment colposcopic differences in epithelial disruption between treatment groups, with only increased erythema noted after nonoxynol-9 use (P=.02).

CONCLUSION

Optical coherence tomography detected epithelial disruption and thinning not identified by colposcopy. Vaginal epithelial thickness, a measure previously available only through biopsy, decreased after nonoxynol-9 use, a finding that may contribute to increased susceptibility to human immunodeficiency virus after frequent use. Optical coherence tomography shows promise for the noninvasive clinical assessment of vaginal epithelial damage.

CLINICAL TRIAL REGISTRATION

UMIN Clinical Trials Registry, www.umin.ac.jp/ctr/index.htm, R000006186.

LEVEL OF EVIDENCE

I.