One of the more widely anticipated additions to the antiretroviral
armamentarium is a new formulation of an older
NRTI, tenofovir. Similar to tenofovir disoproxil fumurate
(TDF), tenofovir alafenamide (TAF) is a prodrug requiring
conversion to its active form. However, TAF primarily
undergoes this process intracellularly, decreasing plasma
concentrations up to 90%.2
With decreased plasma concentrations,
theoretically, TAF could lead to fewer adverse effects
on kidneys and bone mineral density. Phase III comparator
studies are underway with TAF in fixed dose combination
with either emtricitabine or emtricitabine, EVG, and
cobicistat.3–6 Another development in the INSTI class centers
on cabotegravir. As an analog of DTG, cabotegravir is currently
in a number of Phase II studies evaluating its use as
an oral or intramuscular agent. Additionally, its role in dual
therapy when used intramuscularly, along with injectable
rilpivirine, is being evaluated in treatment naïve adults.7,8 The
possibility of using cabotegravir as a form of pre-exposure
prophylaxis is also being explored.