What is HIV? • HIV stands for Human Immunodeficiency Virus. • It is classed as a retrovirus. This means that the virus uses the body’s own cells to reproduce itself.| • While several theories exist, the origin of this virus is still unclear. Read more on what is HIV/AIDS in the attachment.

Study Overview •HPTN 035 was a Phase II/IIb trial that evaluated the safety and effectiveness of the vaginal microbicides PRO 2000 (0.5 percent dose) and BufferGel for preventing male-to-female sexual transmission of HIV. • The study was not designed to compare the two gels, but rather to compare each against a placebo gel with no active ingredient, and with no gel at all. • The study was conducted between February 2005 and September 2008 among 3,099 HIV-negative women at seven clinical research sites in Malawi, South Africa, Zambia, Zimbabwe and the United States. • Women were randomized approximately in equal number to one of four study groups: BufferGel, PRO 2000 gel, placebo gel (with no active ingredient), or no gel. Participants assigned to the three gel groups were instructed to apply gel up to one hour before sexual intercourse using pre-filled applicators.   Click on the attachment to read more.