The pipeline: three to watch.

Four antiretroviral drugs were approved in 2003: emtricitabine (FTC, Emtriva), and nucleoside reverse transcriptase inhibitor (NRTI); the protease inhibitors (PIs) atazanavir (Reyataz) and fosamprenavir (Lexiva); and T-20 (enfuvirtide, Fuzeon), the first of a new anti-HIV drug class, entry inhibitors.