The FDA yesterday approved a new drug for adults whose HIV infection has not responded to treatment with other antiretroviral drugs.

Prezista (darunavir), a new HIV protease inhibitor, is approved to be co-administered with a low-dose of ritonavir and other active anti-HIV agents. Ritonavir, a protease inhibitor approved in 1996, slows the breakdown of Prezista in the body, thereby increasing the concentration of Prezista in the patient's system.

Prezista is manufactured for Tibotec, a division of Ortho Biotech Products.

Infection with HIV causes AIDS, which results in more than 15,000 premature deaths each year in the United States and more than 2.8 million deaths each year worldwide.

The accelerated approval is based on evidence from two randomized, controlled studies comparing the safety and effectiveness of a Prezista-ritonavir combination with other ritonavir-boosted protease inhibitor combinations. Patients in both arms of the trials also used other anti-HIV agents (nucleoside reverse transcriptase inhibitors) with or without enfuvirtide, a fusion inhibitor that inhibits the virus from entering the cell.