The FDA is scheduled to convene a panel of outside experts to review Merck's developmental HIV treatment Isentress on Sept. 5.
Merck is seeking approval to market Isentress to HIV patients who have stopped responding to at least one drug in each of the three available classes of oral antiretroviral therapies.
If approved, Isentress would be the first in a new class of antiretroviral agents called integrase inhibitors that inhibit the insertion of HIV DNA into human DNA. Inhibiting integrase from performing this function blocks the ability of the virus to replicate and infect new cells. There are drugs in use that inhibit two other enzymes critical to the HIV replication process - protease and reverse transcriptase - but currently no approved drugs inhibit integrase.
Last month, the FDA granted Merck’s Isentress application priority review status, indicating the drug addresses an urgent medical need. As a result, Isentress’ review time was "fast-tracked" to six months, instead of the 10 months the process often takes under standard review.
Merck is expecting a final decision on Isentress by mid-October.
Approximately 1 million people in the US are HIV positive, according to statistics from the Centers for Disease Control.