Pfizer has scored a win in Europe after the region’s scientific advisory panel voted to back its first in class HIV medicine Celsentri (maraviroc) for use as a combination treatment in adults who have CCR5-tropic detectable virus and who have become resistant to other available therapies. This is the first new HIV medicine in more than a decade, says Pfizer, and works by blocking HIV’s entry through the CCR5 co-receptor into white blood cells.
In the 24-week MOTIVATE pivotal trials, a regimen including Celsentri substantially cut viral load when compared to so-called optimized background therapy alone. Indeed, almost twice as many patients receiving the Pfizer medicine achieved undetectable viral load (less than 50 copies/ml) than those in the comparison groups, as well as significantly greater increases in the immune boosting CD4 white cells. Side effects were similar across all groups.
It’s great news for Pfizer, which received an approvable letter for maraviroc in June from the US Food and Drug Administration. Although it does not have to conduct additional studies, the panel is believed to have requested changes to the CCR5 antagonist’s labeling before permitting it entry into the marketplace. Previously an FDA panel had voted unanimously to back maraviroc.
In December 2006, Pfizer announced plans to establish a multi-national Expanded Access Programme, a clinical study that provides maraviroc to patients who have limited or no approved treatment options due to resistance or intolerance to existing drug classes. The programme is open for enrollment with a target to enroll patients from over 30 countries.
Meanwhile, the company also received the thumbs up for its antifungal Ecalta (anidulafungin) to treat invasive Candidiasis. The European Commission normally delivers a final decision of product approvability in three to four months from this point.