Tolerability of central nervous system symptoms among HIV-1 infected efavirenz users: analysis of patient electronic medical record data.

Efavirenz (EFV) is a non-nucleoside reverse transcriptase inhibitor indicated for treatment of HIV-1 infection. Despite concern over EFV tolerability in clinical trials and practice, particularly related to central nervous system (CNS) adverse events, some observational studies have shown high rates of EFV continuation at one year and low rates of CNS-related EFV substitution. The objective of this study was to further examine the real-world rate of CNS-related EFV discontinuation in antiretroviral therapy naïve HIV-1 patients. This retrospective cohort study used a nationally representative electronic medical records database to identify HIV-1 patients ≥12 years old, treated with a 1st-line EFV-based regimen (single or combination antiretroviral tablet) from 1 January 2009 to 30 June 2013. Patients without prior record of EFV use during 6-month baseline (i.e., antiretroviral therapy naïve) were followed 12 months post-medication initiation. CNS-related EFV discontinuation was defined as evidence of a switch to a replacement antiretroviral coupled with record of a CNS symptom within 30 days prior, absent lab evidence of virologic failure. We identified 1742 1st-line EFV patients. Mean age was 48 years, 22.7% were female, and 8.1% had a prior report of CNS symptoms. The first year, overall discontinuation rate among new users of EFV was 16.2%. Ten percent of patients (n = 174) reported a CNS symptom and 1.1% (n = 19) discontinued EFV due to CNS symptoms: insomnia (n = 12), headache (n = 5), impaired concentration (n = 1), and somnolence (n = 1). The frequency of CNS symptoms was similar for patients who discontinued EFV compared to those who did not (10.3 vs. 9.9%; P = .86). Our study found that EFV discontinuation due to CNS symptoms was low, consistent with prior reports.