The study investigated the durability of switched therapy and factors associated with the viral rebound among patients on second-line antiretroviral therapy (ART) in Uganda.
A retrospective dynamic cohort of adults initiated on second-line ART after virological failure to first-line ART.
Patients on second-line treatment for at least 6 months between 2007 and 2017 were included. Patients were followed, until they experienced a viral rebound (viral load ≥200 copies/ml). Cumulative probability of viral rebounds and factors associated with viral rebound were determined using Kaplan–Meier methods and Cox proportional hazard models.
One thousand, one hundred and one participants were enrolled of which 64% were women, the median age was 37 years [interquartile range (IQR) 31–43]. The preswitch median CD4+ cell count and viral load were 128 cells/μl (IQR 58–244) and 45 978 copies/ml (IQR 13 827–139 583), respectively. During the 4190.37 person-years, the incidence rate of viral rebound was 83.29 [95% confidence interval (CI) 74.99–92.49] per 1000 person-years. The probability of viral rebound at 5 and 10 years was 0.29 (95% CI 0.26–0.32) and 0.62 (95% CI 0.55–0.69), respectively. The median rebound-free survival was 8.7 years. Young adults (18–24 years) [adjusted hazard ratio (aHR) 2.49, 95% CI 1.32–4.67], preswitch viral load at least 100 000 copies/ml (aHR 1.53, 95% CI 1.22–1.92), and atazanavir/ritonavir (ATV/r)-based second-line (aHR 1.73, 95% CI 1.29–2.32) were associated with an increased risk of viral rebound.
Switched therapies are durable for 8 years after failure of recommended regimens. A high preswitch viral load, ATV/r-based regimens, and young adulthood are risk factors for viral rebound, which underscores the need for more durable regimens and differentiated care services.