POPULATION COUNCIL CLINICAL STUDIES
Protocol 395

Name of study: A substudy to determine the efficacy and safety of the vaginal microbicide Carraguard®, as an inhibitor of human papillomavirus (HPV) infection

Type of study: Substudy

Study phase: n/a

Study design: n/a

Purpose of the study: The purpose of this substudy to the Phase 3 Carraguard trial is to determine whether Carraguard is an inhibitor of human papillomavirus (HPV) infection. This protection has been demonstrated in vitro (Buck et al. 2006a,b), and the Phase 3 trial affords an ideal opportunity to assess the effect of the microbicide on the transmission of HPV.

Since the study began in late 2006, 1,717 participants from the Phase 3 study have been enrolled via a separate consent form and have had additional specimens collected at their final closeout visit. These specimens will be tested and compared on the following information:

• The prevalence and type distribution of genital HPV DNA among Carraguard and placebo users, and the difference between the two groups; and
• The prevalence and type distribution of serum HPV antibodies between Carraguard and placebo users, and the difference between the two groups.

Data on potential confounders, including Pap smear results, demographic data, reproductive history, and sexual activity, will be accessed from the main study. There is a high incidence of cervical cancer in South Africa, and Carraguard use could be significant in the control of cervical disease if found effective in the inhibition of genital HPV infection.

Products to be investigated or studied (including trade and generic names): Carraguard

Study start date: Late 2006

Study end date: March 2007

Study sites and associated numbers of subjects at each site: Empilisweni Centre for Wellness Studies, University of Cape Town (873 participants); Setshaba Research Centre, University of Limpopo/Medunsa campus (665 participants); Isipingo Clinic, Medical Research Council, South Africa (179 participants)

Criteria for inclusion in study (if applicable): Participation in the Phase 3 Carraguard trial

Note: All clinical studies have appropriate approval from the Institutional Review Boards in the countries in which they are being conducted.

Sources

Buck, Christopher B., Patricia M. Day, Cynthia D. Thompson, Jacek Lubkowski, Wuyuan Lu, Douglas R. Lowy, and John T. Schiller. 2006a. "Human α-defensins block papillomavirus infection," Proceedings of the National Academy of Sciences of the United States of America 103(5): 1516–1521.

Buck, Christopher B., Cynthia D. Thompson, Jeffrey N. Roberts, Martin Müller, Douglas R. Lowy, and John T. Schiller. 2006b. "Carrageenan is a potent inhibitor of papillomavirus infection," PLoS Pathogens 2(7): 671–679.