Pfizer's HIV/AIDS drug recommended for approval
US regulators have recommended its first-in-class HIV/AIDS drug
should be approved.
The US Food and Drug Administration's (FDA) Antiviral Drugs Advisory Committee made the recommendation and once the FDA makes it final decision in June, Selzentry (maraviroc) could be the first new type of HIV drug approved in over a decade. Rather than fighting HIV inside white blood cells, it prevents the virus from entering uninfected cells by blocking its predominant entry route, the chemokine (C-C motif) receptor 5 (CCR5). "While the FDA is not bound by the Advisory Committee recommendations, in most cases, the FDA does follow the recommendations," explained Pfizer. The news comes after a difficult period for the beleaguered pharma giant. First, development of its investigational cholesterol drug, torcetrapib, was scrapped, knocking around $20bn (€14.7) off the company's market cap overnight. Then it laid off 10 per cent of its workforce - some 10,000 jobs - closing research and manufacturing facilities in the process, as it looked to restructure the business. Although Pfizer beat its earnings estimates when it announced 'solid' first quarter results last week, it was also forced to reduce its outlook for the year in the face of Norvasc (amlodipine) losing patent protection sixth months early. In the background document Pfizer supplied to the FDA committee, the pharma firm said Selzentry "is safe and effective," and the benefits of the therapy outweigh the risks for patients "having very few or no remaining treatment options available [due to resistance]." The drug will be administered in combination with other antiretroviral therapies, to patients tested to ensure they have a form of HIV susceptible to CCR5 inhibition. However, the good news has been tempered by industry analysts only predicting moderate sales for Selzentry. This is due to the drug's initial small patient population and the potential success of rival drugs waiting in the wings. The analysts estimate that the drug will only earn up to $500m by 2011. Rivals to Pfizer's drug include Merck & Co's integrase inhibitor, Isentress (raltegravir). This is another potential first-in-class drug that prevents HIV viral DNA being integrated into human DNA. Merck & Co has said its plans to file the drug with the FDA in the second quarter of 2007.
