Incidence of symptomatic CSF viral escape in HIV infected patients receiving atazanavir/ritonavir (ATV/r)-containing ART: a tertiary care cohort in western India.

This single-center study attempts to quantify the incidence of symptomatic CSF viral escape (CSFVE) in patients receiving atazanavir/r (ATV/r)-containing regimen. We performed a retrospective analysis of patients receiving ATV/r-containing ART who were diagnosed with symptomatic CSFVE from August 2012 to January 2017. Primary objective was to assess the incidence of symptomatic CSFVE in patients receiving ATV/r-containing ART in clinical practice. Incidence rates were calculated by dividing the number of patients who experienced CSFVE by the number of person-months at risk and summarized as per 10,000 (ten thousand) person-months at risk. Nine hundred thirty-three patients receiving ATV/r containing ART with a total of 36,068 person-months of follow-up were included. Incidence rate of symptomatic CSFVE was 4.4 per 10,000 person-months (95% CI 2.7 to 7.2). The incidence of CSFVE was 9.5 per 10,000 person-months (95% CI 5.7 to 15.7) when the nadir CD4 count was ≤ 200 compared to 0.49 (95% CI 0.07 to 3.5) with a nadir CD4 count > 200 (IRR 19.1 (95% CI 2.93 to 802.8), p < 0.0001). Nadir CD4 count ≤ 200 was associated with substantially increased risk of symptomatic CSFVE, further strengthening efforts to diagnose and treat patients early in disease.