PrEP effective with less than daily dose

PrEP was first proven effective in the 2010 iPrEx study that trialled Truvada (Gilead) — a daily combination therapy comprising the tenofovir and emtricitabine — in men who have sex with men and transgender women. The drug subsequently won FDA approval for PrEP in 2012.

The extended study, iPrExOLE invited HIV-negative participants to continue taking PrEP or continue usual care without the medication. A total of 1603 people participated in the extended trial with 78% choosing to continue with PrEP. During the 72-week trial