On August 27, 2012, the FDA approved Stribild, the newest full-regimen pill taken once a day for HIV+ adults starting treatment for the first time. During clinical study, the pill was commonly referred to as “the Quad” for its four combined drugs: the new integrase inhibitor elvitegravir and a new boosting drug cobicistat, along with tenofovir/emtricitabine (Truvada).
The approval is based on the results from two studies — one that compared Stribild to Atripla (Study 102) and another that compared Stribild to boosted Reyataz (atazanavir) + Truvada (Study 103). At 48 weeks, Stribild controlled HIV <50 copies in 88% of people compared to 84% on Atripla. Fewer who took Stribild stopped due to side effects. Stribild similarly controlled HIV in 90% of people compared to 87% on Reyataz + Truvada, with similar rates of side effects in both regimens.
One ongoing concern with Stribild is its affect on a marker of kidney health called serum creatinine. Cobicistat can raise the level of this marker, which may mean possible kidney dysfunction. However, researchers explained that the drug inhibits kidney tubular secretion, which alters estimated but not actual GFR, or glomerular filtration rate that measures kidney function. Doctors should monitor estimated creatinine clearance, urine glucose and urine protein while people are on treatment as well as serum phosphorus for people with kidney impairment.
HIV+ people who also have hepatitis B may see a worsening of liver disease after stopping Stribild, as both tenofovir and emtricitabine are active against hepatitis B. Patients should work closely with their doctors about how to safely do this.
Uninsured people who need financial assistance for Stribild or for people who need co-pay assistance can contact the Advancing Access Program at 800-226-2056.
See earlier coverage of elvitegravir from Project Inform here and here.