To the Editor:

A robust discussion is underway about the potential use of anti-HIV drugs to prevent HIV infection (also known as pre-exposure prophylaxis or PrEP).  Our study, called iPrEx, provided the first evidence that the daily use of PrEP with the FDA-approved HIV treatment Truvada can significantly reduce HIV infection risk in gay, bisexual and other men who have sex with men (MSM) and transgender women.

Recently, a private healthcare provider began a paid advertising campaign urging the FDA not to even consider approving PrEP — charging that MSM will stop using condoms if PrEP is permitted.

The pros and cons of PrEP use should be vigorously debated — but that debate should be based on facts, rather than the assumption that MSM will not act to protect themselves and others from infection. Here are the facts about the iPrEX study:

• A diverse group of 2,499 HIV-negative MSM and transgender women participated in iPrEx. All participants received a comprehensive package of HIV prevention services. Half also received Truvada, while the other half received a placebo (blank pill).

• The group that received PrEP with Truvada in addition to condoms had 44 percent fewer HIV infections.

• Men in both study groups reduced their risk behaviors and increased their condom use. PrEP does not protect against other sexually transmitted infections and is not a substitute for condom use or other safer sex precautions.

• Ensuring daily pill use will be critical to the success of PrEP. Among those who took PrEP more consistently, the level of protection it provided reached 72 percent to 95 percent.

• Rates of side effects from PrEP were very low. Studies to date also show no evidence of HIV drug resistance associated with PrEP use. HIV testing and medical evaluation before starting PrEP and while using PrEP are important to prevent resistance.

• A daily PrEP dosing regimen was used in the iPrEx study. Additional studies are underway or being planned to look at whether different dosing regimens would be safe and effective.

• The iPrEx study was paid for by the U.S. National Institutes of Health and by the Bill & Melinda Gates Foundation, and was not organized or run by any drug company.

Much work lies ahead to determine whether PrEP can help stop HIV infections in other populations, such as heterosexuals and injection drug users; to better understand possible side effects; support consistent pill use among people who want to use it; and to ensure that PrEP is seen as one element of an HIV prevention strategy that includes regular condom use.

We believe that MSM and all communities have the right to full information about PrEP. More information about iPrEx and PrEP is available at www.iprexnews.com.

Robert Grant, MD, MPH
iPrEx Protocol Chair

This letter is also signed by iPrEx investigators Albert Liu, MD, MPH; Susan Buchbinder, MD; Kenneth Mayer, MD; Pedro Goicochea,MSc, MA; and Jeff McConnell, MA

Editor’s note: This letter is in response to an ad from AIDS Healthcare Foundation that appeared in the March 19, 2011, issue of GA Voice.