Antiretrovirals for Primary HIV Prevention: the Current Status of Pre- and Post-Exposure Prophylaxis
Krakower, D. S., Jain, S., Mayer, K. H. Current HIV/AIDS Reports, (March 2015), 12(1): 127–138, doi: 10.1007/s11904-014-0253-5.
This review provided the most recent findings on pre-and post-exposure prophylaxis (PEP and PrEP, respectively). PEP is most effective when started immediately after high-risk exposure and should be administered in diverse clinical settings. While well-tolerated PEP treatment regimens are available, adherence to PEP medications and attendance at clinical visits is challenging to certain groups of individuals, especially vulnerable populations like men who have sex with men (MSM). The authors noted that efficacy of PrEP ranged from 44 to 75 percent among several studies that demonstrated reductions in HIV incidence. However, in two studies of African women that did not demonstrate PrEP efficacy, medication nonadherence was suggested as the primary explanation for why the two studies did not demonstrate protection with the same regimen. Data from a 72-week open-label study of daily PrEP among MSM and transgender women (iPrEx OLE) suggested that less-than-perfect adherence to daily PrEP still provides high levels of protection. Further, a modeling study of the South African HIV epidemic concluded that providing PrEP to the general population was costly, whereas focused provision of PrEP to those at greatest risk of HIV acquisition was cost-effective. The authors concluded that expansion of PEP and PrEP provision could help decrease the number of new HIV infections globally, but additional research is needed.