Efficacy and safety of maraviroc vs. efavirenz in treatment-naive patients with HIV-1: 5-year findings.

Abstract

OBJECTIVE:

Maraviroc, a chemokine co-receptor type 5 (CCR5) antagonist, has demonstrated comparable efficacy and safety to efavirenz, each in combination with zidovudine/lamivudine, over 96 weeks in the Maraviroc vs. Efavirenz Regimens as Initial Therapy (MERIT) study. Here we report 5-year findings.

DESIGN:

A randomized, double-blind, multicenter phase IIb/III study with an open-label extension phase.

METHODS:

Treatment-naive patients with CCR5-tropic HIV-1 infection (Trofile) received maraviroc 300 mg twice daily or efavirenz 600 mg once daily, and zidovudine/lamivudine 300 mg/150 mg twice daily. After the last patient's week 96 visit, the study was unblinded and patients could enter a nominal 3-year open-label phase. Endpoints at the 5-year nominal visit (week 240) included proportion of patients (CCR5 tropism re-confirmed by enhanced sensitivity Trofile) with viral load (plasma HIV-1 RNA) below 50 and 400 copies/ml, and change from baseline in CD4(+) cell count, as well as safety.

RESULTS:

The proportion of patients maintaining viral load below 50 copies/ml was similar between treatment arms throughout the study and at week 240 (maraviroc 50.8% vs. efavirenz 45.9%). Maraviroc-treated patients had a greater increase from baseline in mean CD4(+) cell count than efavirenz-treated patients at week 240 (293 vs. 271 cells/μl, respectively). Fewer patients on maraviroc vs. efavirenz experienced treatment-related adverse events (68.9 vs. 81.7%) and discontinued as a result of any adverse event (10.6 vs. 21.3%).

CONCLUSION:

Maraviroc maintained similar long-term antiviral efficacy to efavirenz over 5 years in treatment-naive patients with CCR5-tropic HIV-1. Maraviroc was generally well tolerated with no unexpected safety findings or evidence of long-term safety concerns.

• Authors: David A Cooper, Jayvant Heera, Prudence Ive, Mariette Botes, Edwin Dejesus, Robert Burnside, Nathan Clumeck, Sharon Walmsley, Adriano Lazzarin, Geoffrey Mukwaya, Michael Saag, Elna van Der Ryst
• Journal: AIDS (London, England) (AIDS) Vol. 28 Issue 5 Pg. 717-25 (Mar 13 2014) ISSN: 1473-5571 [Electronic] England
• PMID: 24983542 (Publication Type: Clinical Trial, Phase II, Clinical Trial, Phase III, Comparative Study, Journal Article, Multicenter Study, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Alkynes
• Anti-HIV Agents
• Benzoxazines
• Cyclohexanes
• Cyclopropanes
• Triazoles
• efavirenz
• Maraviroc

Topics

• Adolescent
• Adult
• Aged
• Alkynes
• Anti-HIV Agents (adverse effects, therapeutic use)
• Antiretroviral Therapy, Highly Active (adverse effects, methods)
• Benzoxazines (adverse effects, therapeutic use)
• CD4 Lymphocyte Count
• Cyclohexanes (adverse effects, therapeutic use)
• Cyclopropanes
• Double-Blind Method
• Drug-Related Side Effects and Adverse Reactions (epidemiology)
• Female
• HIV Infections (drug therapy, virology)
• HIV-1 (isolation & purification)
• Humans
• Male
• Maraviroc
• Middle Aged
• Treatment Outcome
• Triazoles (adverse effects, therapeutic use)
• Viral Load
• Young Adult