Pfizer's maraviroc gets nod from FDA panel, likely to become first HIV entry blocker

World drug giant Pfizer says that the US Food and Drug Administration's Antiviral Drugs Advisory Committee voted unanimously to recommend the approval of its CCR5 antagonist maraviroc for use along with other antiretrovirals for treatment-experienced patients infected with CCR5-tropic HIV-1.

If approved, maraviroc would be the first member of a new class of oral HIV drugs in more than a decade. Discovered by Pfizer scientists in 1997, the agent works by blocking viral entry to human cells. Rather than fighting HIV inside white blood cells like antiretrovirals, it prevents the virus from entering uninfected cells by blocking its predominant entry route, the CCR5 co-receptor.

Thomas Wiesel Partners analyst Peter Lawson expects maraviroc to earn $25.0 million in 2007 and $375.0 million by 2010. However, rival HIV entry blockers in development by Incyte and Schering-Plough might have been approved by the time Pfizer is ready to market maraviroc.