HIV prevention advocates from three major civil society organizations today emphasized the importance of continued research into new HIV prevention options, despite the recent discontinuation of the Phase III effectiveness trials of the microbicide candidate, cellulose sulfate (CS).
CS was one of the four microbicide candidates in Phase III effectiveness trials for prevention of HIV and other sexually transmitted infections. CONRAD, a reproductive health research organization, was conducting Phase III trials to assess its effectiveness in Benin, India, South Africa, and Uganda. Another Phase III trial of CS sponsored by Family Health International was underway in Nigeria.
At the recommendation of their respective Data Safety Monitoring Boards both sponsors chose to discontinue their CS trials after findings from the CONRAD trial suggested that CS might be contributing to an increased risk of HIV infection. Although review of the data from the Nigerian trial found no evidence of increased risk, FHI felt that the only responsible course of action was to halt its study also.
"Of course we wish the results had been different, but learning what doesn't work can be just as important to progress as learning what does work," observed Lori Heise, Director of the Global Campaign for Microbicides (GCM). "It's also reassuring that the independent Data Safety and Monitoring Committees, put in place to identify problems early on in a trial, appear to have worked well. Advocates have been instrumental in pushing for extra mechanisms to help protect participant safety."
African advocates are following the trials conducted in their countries particularly closely, reported Manju Chatani, Coordinator of the African Microbicide Advocacy Group (AMAG). "Scientists scrutinized the data available on cellulose sulfate before the Phase III trials started, including safety results from 11 clinical trials done in Africa, India and the US. All the data suggested that the product was safe and should proceed into Phase III trials," she said.
"This is a setback but it does not detract from the issue that women still don't have the tools they need to protect themselves from HIV", Chatani added. "And African women, especially, urgently need more prevention options. So while we need concrete answers to why this happened as soon as possible, we must continue to research new options so women don't have to ask for permission to protect themselves".
Dr. Kim Dickson, an African physician who serves on the boards of both GCM and AMAG, noted that care and treatment of trial participants are among the top concerns of both groups, along with clinical trial ethics. "At civil society's insistence, the trial investigators forged written agreements in advance to assure that any women who sero-converted while enrolled in the trial would get ongoing care and treatment, including anti-retroviral drugs as needed", she said. "Our priority now is to make sure that advocates' and community questions about this trial and future research are heard and addressed as soon as possible."
Adding his perspective, Director of the AIDS Vaccine Advocacy Coalition (AVAC) Mitchell Warren observed that "Getting a negative result for one product certainly doesn't signal failure for the microbicide field or broader biomedical HIV prevention research effort as a whole. The nature of research is that the information gathered is cumulative", he continued. "Each trial result is a puzzle piece and, together, they make up the complex picture that will show us how to develop successful new HIV prevention tools."
Heise concluded by noting that "The real heroines and heroes in this are the people who enroll in clinical trials because they know how urgently new prevention tools are needed. In Benin, South Africa, and Uganda, the African countries in which the CS trials were being done, between one third and one half of all women of reproductive age are already HIV positive", she added. "It is essential to build on what has been learned here and proceed with the research as rapidly as possible. Millions of women's lives are at stake."
