Successful Viral Suppression With Subsequent Efavirenz-Based Regimen in HIV-1-Infected Patients Who Stop Nevirapine Prior to Discontinuation of the NRTI Backbone

Abstract

Objective: To study antiviral response of efavirenz (EFV)-based antiretroviral therapy (ART) in HIV-1-infected patients who had previously discontinued nevirapine (NVP) and continued the nucleoside reverse transcriptase inhibitor (NRTI) backbone for 7 to 14 days after stopping NVP. Methods: A retrospective cohort study was conducted in patients who discontinued NVP. CD4 count and plasma HIV-1 RNA levels were monitored through 48 weeks of EFV-based regimen. Results: Forty-five patients were eligible with a mean ± SD age of 37 ± 11 years; 60% were males. Median (interquartile range [IQR]) baseline CD4 count was 43 (19-150) cells/mm³ and median (IQR) plasma HIV-1 RNA was 5.7 (5.3-5.9) log copies/mL. Median (IQR) duration from stopping NVP to initiating EFV was 13 (7-18) days. At 48 week, 33 (73.3%) of 45 patients achieved plasma HIV-1 RNA <50 copies/mL. At week 12, 24, and 48, median CD4 counts were 193, 238, and 268 cells/mm³, respectively (P < .05). No studied risk factor was associated with achieving HIV-1 RNA <50 copies/mL at 48 weeks (P > .05). Conclusion: The strategy of extended short half-life NRTIs in the regimen after discontinuation of NVP is justified.

Keywords

efavirenz nevirapine allergy efficacy Thailand

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