PrEP Works in Clinical Practice

In July 2012, the FDA approved use of tenofovir/FTC for pre-exposure prophylaxis (PrEP). However, uptake has been slower than desired, and little is known about effectiveness outside of clinical trials. Now, investigators at Kaiser Permanente in San Francisco have documented their experience with PrEP use by members at high risk for HIV infection who were referred to a specialized PrEP program.

Of the 1045 individuals who were referred to the program between July 2012 and February 2015, 835 were evaluated and 657 started PrEP (including 20 who discontinued use during the study period and then restarted it). PrEP initiators had a mean age of 37, and 99% were men who have sex with men; the mean duration of PrEP use was 7.2 months. Initiators were significantly more likely than noninitiators to report having multiple sex partners and prior PrEP use.

Thirty percent of the 657 PrEP initiators received a sexually transmitted disease diagnosis during the first 6 months of use, and 50% received one during the first year. However, there were no new HIV diagnoses over the 388 person-years of follow-up. Among the 143 initiators who reported on their sexual behavior, 74% stated that their number of sexual partners was unchanged.