The US Food and Drug Administration (FDA) has granted accelerated approval Merck’s integrase inhibitor, raltegravir (Isentress).
Approval of the drug was based upon safety and efficacy results from the BENCHMARK 1 and BENCHMARK 2 studies .Encouraging 48-week data were presented to a recent scientific conference in the US.
Raltegravir is the first inhibitor of HIV’s integrase enzyme, which acts to integrate HIV’s genetic material into human immune cells.
The approved dose of raltegravir is 400mg twice daily in combination with other antiretroviral drugs. Raltegravir is an important treatment option for patients with extensive experience of antiretroviral therapy who have resistance to drugs from the main three classes.
The side-effects most commonly associated with raltegravir are diarrhoea, nausea, and headache.
Some treatment activists have expressed concern that the drug, which is priced at a little under $10,000 per year, will be too expensive for some when used alongside other new agents such as maraviroc (Celsentri), which has a slightly higher price tag ($10,585). However Merck says that its price for Isentress is broadly in line with other new antiretrovirals, such as Bristol Myers-Squibb's Reyataz (atazanavir) and Tibotec's Prezista (darunavir)
Approval for raltegravir in Europe is expected in 2008.