Long-term effectiveness of unboosted atazanavir plus abacavir/lamivudine in subjects with virological suppression: A prospective cohort study

• Published in: Medicine (Baltimore) Vol. 95; no. 40; p. e5020
• Main Authors: Llibre, Josep M., Cozzi-Lepri, Alessandro, Pedersen, Court, Ristola, Matti, Losso, Marcelo, Mocroft, Amanda, Mitsura, Viktar, Falconer, Karolin, Maltez, Fernando, Beniowski, Marek, Vullo, Vincenzo, Hassoun, Gamal, Kuzovatova, Elena, Szlavik, János, Kuznetsova, Anastasiia, Stellbrink, Hans-Jürgen, Duvivier, Claudine, Edwards, Simon, Laut, Kamilla, Paredes, Roger
• Format: Journal Article
• Language: English
• Published: United States The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved 01.10.2016; Wolters Kluwer Health
• Subjects: Adult; Age Factors; Anti-HIV Agents - administration & dosage; Anti-HIV Agents - adverse effects; Anti-HIV Agents - therapeutic use; Atazanavir Sulfate - administration & dosage; Atazanavir Sulfate - adverse effects; Atazanavir Sulfate - therapeutic use; Dideoxynucleosides - administration & dosage; Dideoxynucleosides - adverse effects; Dideoxynucleosides - therapeutic use; Drug Combinations; Drug Therapy, Combination; Female; HIV Protease Inhibitors - therapeutic use; HIV-1 - drug effects; Humans; Lamivudine - administration & dosage; Lamivudine - adverse effects; Lamivudine - therapeutic use; Male; Middle Aged; Observational Study; Prospective Studies; Ritonavir - therapeutic use; Sex Factors; Viral Load - drug effects
• ISSN: 0025-7974; 1536-5964; 1536-5964
• DOI: 10.1097/MD.0000000000005020

Effectiveness data of an unboosted atazanavir (ATV) with abacavir/lamivudine (ABC/3TC) switch strategy in clinical routine are scant.We evaluated treatment outcomes of ATV + ABC/3TC in pretreated subjects in the EuroSIDA cohort when started with undetectable plasma HIV-1 viral load (pVL), performing a time to loss of virological response (TLOVR <50 copies/mL) and a snapshot analysis at 48, 96, and 144 weeks. Virological failure (VF) was defined as confirmed pVL >50 copies/mL.We included 285 subjects, 67% male, with median baseline CD4 530 cells, and 44 months with pVL ≤50 copies/mL. The third drug in the previous regimen was ritonavir-boosted atazanavir (ATV/r) in 79 (28%), and another ritonavir-boosted protease inhibitor (PI/r) in 29 (10%). Ninety (32%) had previously failed with a PI. Proportions of people with virological success at 48/96/144 weeks were 90%/87%/88% (TLOVR) and 74%/67%/59% (snapshot analysis), respectively. The rates of VF were 8%/8%/6%. Rates of adverse events leading to study discontinuation were 0.4%/1%/2%. The multivariable adjusted analysis showed an association between VF and nadir CD4+ (hazard ratio [HR] 0.63 [95% confidence interval [CI]: 0.42-0.93] per 100 cells higher), time with pVL ≤50 copies/mL (HR 0.87 [95% CI: 0.79-0.96] per 6 months longer), and previous failure with a PI (HR 2.78 [95% CI: 1.28-6.04]). Resistance selection at failure was uncommon.A switch to ATV + ABC/3TC in selected subjects with suppressed viremia was associated with low rates of VF and discontinuation due to adverse events, even in subjects not receiving ATV/r. The strategy might be considered in those with long-term suppression and no prior PI failure.