Influence of Sex/Gender and Race on Responses to Raltegravir Combined With Tenofovir-Emtricitabine in Treatment-Naive Human Immunodeficiency Virus-1 Infected Patients: Pooled Analyses of the STARTMRK and QDMRK Studies

Open Forum Infect Dis. 2017 Feb 28;4(1):ofw047. doi: 10.1093/ofid/ofw047. eCollection 2017 Winter.

Abstract

Background: Antiretroviral therapy in human immunodeficiency virus (HIV)-infected women and blacks merits particular scrutiny because these groups have been underrepresented in clinical trials.

Methods: To document the effects of raltegravir across sex and racial lines, we conducted a pooled subgroup analysis of the efficacy and safety of raltegravir 400 mg BID plus tenofovir-emtricitabine by sex (women vs men) and self-identified race (black vs non-black) using phase 3 studies in treatment-naive patients.

Results: Study participants included 42 black women, 102 non-black women, 48 black men, and 477 non-black men. Clade B infections were less common in women (43.8%) than men (84.6%) and in blacks (45.6%) than non-blacks (80.5%). Baseline CD4 counts were ≤200 cells/µL in 52.2% of blacks and 31.6% of non-blacks. Black men had the largest proportion of patients with baseline CD4 counts <50 cells/µL and the highest nontreatment-related discontinuation rate among the 4 sex-by-race subgroups. Human immunodeficiency virus-ribonucleic acid levels <50 copies/mL were achieved at week 48 in 92.7% (95% confidence interval [CI], 80.1-98.5) of black women, 93.6% (95% CI, 86.6-97.6) of non-black women, 82.9% (95% CI, 67.9-92.8) of black men, and 91.4% (95% CI, 88.4-93.8) of non-black men. Serious clinical adverse events were reported in 9.0% of women versus 8.8% of men and in 11.1% of blacks versus 8.5% of non-blacks.

Conclusions: In this post hoc analysis of patients with previously untreated HIV-1 infection receiving raltegravir plus tenofovir-emtricitabine, generally comparable results were achieved across sex and racial subgroups. However, black men had a lower response rate than either black women or non-black men, partially attributable to lower baseline CD4 counts and higher discontinuation rates.

Keywords: QDMRK; STARTMRK; raltegravir; subgroup analyses.