Tudobest-LE Tablets TUDOBEST-LE contains a fixed-dose triple combination of Tenofovir Disoproxil Fumarate (TDF), Efavirenz (EFV), and Lamivudine (3TC). TDF and 3TC are nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) that undergo intracellular phosphorylation to their active triphosphate metabolites. These metabolites act as competitive inhibitors of HIV-1 reverse transcriptase and cause DNA chain termination upon incorporation into viral DNA. Efavirenz is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that binds directly to HIV-1 reverse transcriptase near the catalytic site, causing an allosteric conformational change that inhibits RNA-dependent and DNA-dependent DNA polymerase activities. TUDOBEST-LE is indicated as a complete regimen for the treatment of Human Immunodeficiency Virus Type 1 (HIV-1) infection in adults and pediatric patients.