Treatment = Prevention
In an opening plenary session of the IAS Conference in Rome, Dr. Robin Shattock, from the Imperial College in London, said that this is the right time to consider a combination of biomedical and non-biomedical strategies to prevent HIV infection. During his talk, he also coined a new term for the concept of treatment equals prevention, calling it “Treatment 4 Prevention” or T4P.
Combinations of non-biomedical strategies aimed at individual behavioral change and community intervention to reduce HIV risk and vulnerability have been applied for nearly three decades, with differing success. These include sexually transmitted infection diagnosis and treatment, HIV education and knowledge of HIV serostatus, condom social marketing, rights-based behavioral change, prevention of mother-to-child transmission, needle exchange, blood safety, infection control in healthcare, and legal protection for people living with HIV.
However, a number of new biomedical tools (or prevention technologies) have demonstrated success in randomized controlled trials including:
--early use of antiretroviral treatment (ART) (treatment for prevention (T4P)) by an HIV-infected individual has been shown to reduce heterosexual transmission to an uninfected partner by 96% (HPTN052)
--medical male circumcision (MMC) (57%);
--daily oral tenofovir (TDF) plus emtricitabine (FTC) used as pre-exposure prophylaxis (oral-PrEP) by HIV-negative men who have sex with men (MSM) (iPrEX study) (44%);
--1% tenofovir gel (microbicide) applied vaginally before and after sex by HIV-negative women as topical pre-exposure prophylaxis (CAPRISA 004 study) (39%);
--a prime-boost HIV vaccine regimen(RV144 study) (31% effectiveness).
He also noted the convergence of initiatives (e.g. T4P and PrEP). For example, one combined strategy to evaluate would be T4P for the infected partner combined with antiretroviral (ARV) PrEP for the HIV-negative partner. At least 18% of sexual transmissions in the HPTN052 trial may have been acquired from partners outside the primary relationship. Thus the offer of ARV PrEP for the HIV-negative partner together with T4P for the infected partner may provide a more cost-effective option per infection averted.
This is an exciting time in HIV medicine. The data supporting T4P and PrEP stand out at this meeting as important strategies for clinicians. Certainly, more widespread HIV testing and referring people to medical care make very good sense and appear to work to prevent “forward transmission” of HIV.
The role of PrEP is something we also need to embrace. While not for everyone, it makes sense to think about this strategy in discordant couples, according to Dr. Shattuck.
The US Centers for Disease Control and Prevention is developing guidance on this, but in the meantime, we should be thinking of how and where PrEP fits in our overall patient care strategies. While PrEP makes sense, we need to consider variables such as reimbursement, adherence to treatment, patient risk-reduction education, who will initiate and follow patients on PrEP, and the like. While PrEP may not be “ready for prime time,” we should begin to think of this strategy as another piece of T4P.
Reference: Shattock R. The Combined approach to preventing HIV infection. Presented July 18, 2011, at the 6th IAS Conference on HIV Pathogenesis, Treatment and Prevention, Rome, Italy. Oral presentation, Monday Plenary Session, MOPL01.
July 18, 2011
IAS 2011: Treatment = Prevention
Treatment = Prevention
Source: Reporting for PRN News from Rome, Italy: Bill Valenti, MD