TUDOBEST-L Tablets TUDOBEST-L is a fixed-dose dual antiretroviral combination of Tenofovir Disoproxil Fumarate (a nucleotide reverse transcriptase inhibitor) and Lamivudine (a nucleoside reverse transcriptase inhibitor). Following administration, tenofovir disoproxil fumarate is converted to tenofovir and phosphorylated to tenofovir diphosphate, while lamivudine is phosphorylated to lamivudine 5'-triphosphate. Both active metabolites competitively inhibit viral reverse transcriptase and incorporate into nascent viral DNA, causing DNA chain termination and blocking HIV-1 replication. It is indicated in combination with other antiretroviral therapies for the management of HIV-1 infection in adults and pediatric patients.