Duovir Tablets Duovir is a fixed-dose combination containing two nucleoside reverse transcriptase inhibitors (NRTIs), Lamivudine and Zidovudine. Both components are intracellularly phosphorylated to their active triphosphates, lamivudine 5'-triphosphate and zidovudine 5'-triphosphate, which compete with natural nucleosides for incorporation into viral DNA via HIV-1 reverse transcriptase. Incorporation results in viral DNA chain termination and inhibition of viral replication. Duovir is indicated in combination with other antiretroviral agents for the treatment of Human Immunodeficiency Virus Type 1 (HIV-1) infection in adults and pediatric patients weighing at least 30 kg.