August 2, 2012
Gilead Sciences Inc. said elvitegravir, a component in its four-drug HIV treatment Quad, showed similar efficacy and tolerability compared to Merck & Co.'s Isentress in a two-year trial.
The results of the study in previously treated HIV patients were presented at the 19th International AIDS Conference. In the late-stage clinical trial, elvitegravir met the primary clinical goal of being non-inferior to Isentress, the researchers said.
"As patients are living with HIV longer, there is a continued need for new treatment options, particularly those that are effective against strains of the virus that have developed resistance to currently available therapies," said Dr. Richard Elion, lead investigator.
US and European health regulators are reviewing elvitegravir for approval. The US Food and Drug Administration is expected to make an approval decision on Quad in August.
Both once-daily elvitegravir and twice-daily Isentress (raltegravir) are integrase inhibitors: They interfere with HIV's replication by thwarting its ability to integrate into the genetic material of human cells.
Both treatment groups had similar rates of adverse side effects, side effect-related discontinuations, and drug resistance development; however, reports of diarrhea were more common among study subjects taking elvitegravir (13 percent vs. 8 percent).