The first case of HIV contraction while taking preventative drugs has been documented
For the first time ever, researchers have documented a case of an individual contracting HIV while reportedly adhering well to the daily regimen of PrEP, aka pre-exposure prophylaxis -- a antiretroviral drug cocktail used to prevent people from contracting HIV.
According to a case that has been documented and presented by David Knox, MD, an HIV specialist at the Maple Leaf Medical Clinic:
Evidence suggests that the individual in question, a 43-year-old man who has sex with men, adhered well to PrEP over the long-term. Nevertheless, after 24 months on Truvada he tested positive for HIV. Initial tests indicated that he was acutely (very recently) infected: He tested positive for the p24 antigen, which appears within about three weeks of HIV infection and disappears a few weeks afterward; and at that time he tested negative for HIV antibodies, which typically appear two to eight weeks after infection.
In light of this new information, scientists have concluded that it is, in fact, possible for individuals who are adherent to PrEP to contract HIV when they are exposed to a particular virus that is resistant to drugs.
"After 32 years of experience with HIV research, I have learned never to say 'never'," said Robert M. Grant, MD, MPH, a professor at the University of California, San Francisco.
However, there is still more than a silver lining when it comes to HIV preventative medication.
Despite this case of infection while adhering to the regimen, research still suggests that gay men who take Truvada at least four times a week are still more than 99 percent protected against HIV, though CDC guidelines advise taking Truvada daily for maximum protection.
According to an article from Poz, "real-world use of Truvada as HIV prevention has suggested it is indeed highly effective." For example, none of the more than 1,400 generally high-risk individuals taking PrEP through the Kaiser Permanente San Francisco PrEP program have contracted HIV to date, despite their very high rate of other sexually transmitted infections, including hepatitis C virus (HCV) in two of them.
So anyone on the PrEP regimen can breathe a sigh of relief -- while this one case is definitely concerning, experts in the PrEP field suggest that such failures will likely remain rare.
Learn more about controversy surrounding Truvada:
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