title: A review of the virological efficacy of the 4 World Health Organization-recommended tenofovir-containing regimens for initial HIV therapy.
abstract: We systematically reviewed studies of the virological efficacy of the 4 new tenofovir (TDF)-containing regimens recommended for initial antiretroviral (ARV) therapy in the 2010 World Health Organization ARV Treatment Guidelines. Thirty-three studies assessed the efficacy of 1 or more TDF-containing regimens: TDF/lamivudine (3TC)/nevirapine (NVP) (n = 3), TDF/ emtricitabine (FTC)/NVP (n = 9), TDF/3TC/efavirenz (EFV) (n = 6), and TDF/FTC/EFV (n = 19). TDF/3TC/NVP was the least well-studied and appeared the least efficacious of the 4 regimens. In 2 comparative studies, TDF/3TC/NVP was associated with significantly more virological failure than AZT/3TC/NVP; a third study was terminated prematurely because of early virological failure. TDF/FTC/NVP was either equivalent or inferior to its comparator arms. TDF/3TC/EFV was equivalent to its comparator arms. TDF/FTC/EFV was equivalent or superior to its comparator arms. Possible explanations for these findings include the greater antiviral activity of EFV versus NVP and longer intracellular half-life of FTC-triphosphate versus 3TC-triphosphate. Further study of TDF/3TC/NVP is required before it is widely deployed for initial ARV therapy.
authors.affiliation: Department of Medicine, Division of Infectious Diseases, Stanford University, California 94305-5107, USA. micheletang@gmail.com
authors.forename: Michele W
authors.initials: MW
authors.lastname: Tang
authors.forename: Phyllis J
authors.initials: PJ
authors.lastname: Kanki
authors.forename: Robert W
authors.initials: RW
authors.lastname: Shafer
mesh_terms: D000225:Adenine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D000480:Alkynes; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D048588:Benzoxazines / Q000008:administration & dosage; D018791:CD4 Lymphocyte Count; D003521:Cyclopropanes; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D004359:Drug Therapy, Combination; D000068679:Emtricitabine; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D019259:Lamivudine / Q000008:administration & dosage; D019829:Nevirapine / Q000008:administration & dosage; D063065:Organophosphonates / Q000008:administration & dosage*; D000068698:Tenofovir; D017211:Treatment Failure; D019562:Viral Load; D014944:World Health Organization
chemical_list: D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D063065:Organophosphonates; D003841:Deoxycytidine; D019259:Lamivudine; D019829:Nevirapine; D000068698:Tenofovir; D000068679:Emtricitabine; D000225:Adenine; C098320:efavirenz