Study of Once Daily Elvucitabine Versus Lamivudine in Participants With a Documented M184V Mutation

Human immunodeficiency virus (HIV)-1 infected participants receiving long-term therapy with lamivudine or emtricitabine (nucleoside reverse transcriptase inhibitors \[NRTIs\]) are at risk for the development of a mutation at position M184 on the HIV reverse transcriptase gene. This mutation confers resistance to both drugs (\>100 fold increase in the concentration of drug producing 50% inhibition \[IC50\]).

In-vitro studies with elvucitabine have shown that HIV-1 isolates with the M184V mutation show only a 10-fold increase in IC50 as compared to wild type HIV-1. Alexion Pharmaceuticals Inc. intention is to demonstrate that 10 milligrams (mg) of elvucitabine, administered once per day for 14 days with continued background anti-HIV-1 medications, will demonstrate a fall in HIV-1 ribonucleic acid (RNA) plasma levels, as compared to baseline. The data from this study will guide dosing in future long-term studies in HIV-1 infected participants with the M184V mutation.