title: Is zidovudine first-line therapy virologically comparable to tenofovir in resource-limited settings?
abstract: OBJECTIVE
  To compare virologic success between adult patients on tenofovir (TDF) and zidovudine (AZT)-containing first-line antiretroviral (ART) regimens in 10 rural clinics in Lesotho, Southern Africa.
  
  
  METHODS
  Multicentre cross-sectional study, patients ≥16 years, on first-line ART ≥6 months, receiving AZT/lamivudine (3TC) or TDF/3TC combined with efavirenz (EFV) or nevirapine (NVP). Patient characteristics and clinical/therapeutic history were collected on the day of blood draw for viral load (VL). Analysis was stratified for non-nucleoside reverse transcriptase inhibitor (EFV or NVP). A logistic regression model weighted for patients' baseline characteristics was used to assess the likelihood of virologic success (<80 copies/ml) in patients with TDF- as compared to AZT-backbones.
  
  
  RESULTS
  In total 1539 patients were included in the analysis. Most were clinically and immunologically stable (clinical failure: 2.7% (AZT) and 2.8% (TDF); immunological failure: 4.6% (AZT) and 4.8% (TDF)). In EFV-based regimens (n = 1162), TDF was significantly associated with higher rates of virologic suppression than AZT (93.8% vs. 88.1%; weighted odds ratio: 2.15 (95% CI: 1.29-3.58; P = 0.003)). In NVP-based regimens, a similar trend was observed, but not significant (89.4% vs. 86.7%; 1.99 (0.83-4.75, P = 0.121)).
  
  
  CONCLUSIONS
  These findings support the WHO recommendation to use TDF/3TC/EFV as first-line regimen. They do, however, not support the recommendation that patients who are clinically stable on AZT should continue on this first-line regimen.
authors.affiliation: Medical Services and Diagnostics, Clinical Research Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland.|University of Basel, Basel, Switzerland.
authors.forename: Niklaus D
authors.initials: ND
authors.lastname: Labhardt
authors.affiliation: Molecular Virology, Department Biomedicine - Petersplatz, University of Basel, Basel, Switzerland.
authors.forename: Joëlle
authors.initials: J
authors.lastname: Bader
authors.affiliation: SolidarMed, Swiss Organization for Health in Africa, Maseru, Lesotho.
authors.forename: Thabo Ismael
authors.initials: TI
authors.lastname: Lejone
authors.affiliation: SolidarMed, Swiss Organization for Health in Africa, Maseru, Lesotho.
authors.forename: Isaac
authors.initials: I
authors.lastname: Ringera
authors.affiliation: SolidarMed, Swiss Organization for Health in Africa, Maseru, Lesotho.
authors.forename: Daniel
authors.initials: D
authors.lastname: Puga
authors.affiliation: University of Basel, Basel, Switzerland.|Biostatistics Department, Epidemiology and Public Health Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland.
authors.forename: Tracy R
authors.initials: TR
authors.lastname: Glass
authors.affiliation: Molecular Virology, Department Biomedicine - Petersplatz, University of Basel, Basel, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Klimkait
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D000328:Adult; D000480:Alkynes; D019380:Anti-HIV Agents / Q000494:pharmacology / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D048588:Benzoxazines / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D003521:Cyclopropanes; D005260:Female; D006678:HIV / Q000187:drug effects*; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D006295:Health Resources; D006801:Humans; D019259:Lamivudine / Q000627:therapeutic use; D007927:Lesotho; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D063065:Organophosphonates / Q000494:pharmacology / Q000627:therapeutic use*; D000068698:Tenofovir; D019562:Viral Load; D015215:Zidovudine / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D063065:Organophosphonates; D019259:Lamivudine; D015215:Zidovudine; D000068698:Tenofovir; D000225:Adenine; C098320:efavirenz
keywords: Africa; Carga Viral; HIV; Inhibidor Nucleósido de la Transcriptasa Inversa; Tenofovir; Terapia Antirretroviral; VIH; Zidovudina; anti-retroviral therapy; charge virale; inhibiteur de la transcriptase inverse nucléosidique; l'Afrique; nucleoside reverse transcriptase inhibitor; tenofovir; thérapie antirétrovirale; ténofovir; viral load; zidovudine; África