Single-tablet regimen is associated with reduced efavirenz withdrawal in antiretroviral naïve or switching for simplification HIV-infected patients

of results Overall, 533 patients, starting EFV-containing regimen from May 1998 to March 2012, were included (51.2% naı̈ve, 48.8% switched). Patients characteristics: males 70.7%, median age 39 years, injecting drug use (IDU) 11.2%, median nadir CD4 194/ mmc, median CD4 at EFV start 305/mmc: 38.7% started BID regimen, 43.9% OD regimen and 17.4% STR. At survival analysis, the overall proportion of EFV interruption was 19.1% at 1 year and 33.0% at 3 years; interruption for virological failure were 2.8% and 7.4% and for toxicity 10.2% and 15.9%, respectively. CNS-SE accounted for about half of interruptions for toxicity (5.7% and 8.0% at 1 and 3 years, respectively). Naı̈ve patients had a higher risk of interruption as compared to switched patients: 37.7% vs. 28.0% at 3 years (p 0.06). While no significant difference was observed comparing OD vs. B ID regimens, starting with STR was associated with significant lower proportion of overall interruption at 3 years (17.1% vs. 36.6%, pB0.01). No virological failure was observed with STR up to 3 years (0.0% vs. 8.9%, p 0.05); no difference of interruption by overall toxicity and higher, though non-significant, frequency of interruption by CNS-SE (12.8% vs. 6.8%) were also observed. STR also accounted for lower proportion of interruption by patient wish, including low adherence (1.5% vs. 12.3%, p 0.01). At adjusted Cox model, STR (HR: 0.44; 95% CI: 0.26 0.77) and male gender (HR: 0.71; 95% CI: 0.53 0.97) were associated with lower risk of EFV interruption and IDU with higher risk (HR: 1.64; 95% CI: 1.11 2.42).