Real‐world clinical and laboratory changes after switching to two‐drug regimen in HIV ‐suppressed individuals: 48 weeks and beyond

Introduction Two‐drug regimens (2DRs) may reduce long‐term drug toxicities and drug‐drug interactions for people with HIV (PWH) on antiretroviral therapy (ART). This study evaluated clinical and laboratory outcomes in PWH who switched from standard ART to dolutegravir and lamivudine (DTG + 3TC) in real‐world settings. Methods We retrospectively identified virally suppressed PWH who switched from standard ART to DTG + 3TC at Queen Elizabeth Hospital, Hong Kong, China. They were grouped by age (PWH <50 years: PWH < 50; PWH > =50 years: PWH > =50). Their demographics, clinical and laboratory data before and 48 weeks after switch were compared. Results Subjects included 352 PWH (84.7% male, 48.7% PWH > =50, median ART duration 8.3 years). At 48 weeks post‐switch, 96.0% maintained DTG + 3TC with two (1.1%) in the PWH < 50 and three (1.7%) in the PWH > =50 experienced virological failure. There was no significant difference in virological failure (hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.11, 3.77, p = 0.613) or 2DR discontinuation (HR 0.95, 95% CI 0.33, 2.71, p = 0.926; restricted mean survival time (RMST) difference 0.23 weeks, 95% CI −0.64, 1.10, p = 0.600) between the groups. PWH > =50 exhibited a greater total cholesterol reduction than PWH < 50 post‐switch (median change −4.8% (IQR −17.5%, 5.9%) versus 0.4% (IQR −8.1%, 8.2%), p = 0.005). Two sensitivity analyses excluding lipid‐lowering drug users and restricting to INSTI‐based ART users before switch yielded negative results. Conclusions In this Chinese‐majority cohort, switching from standard ART to DTG + 3TC was well tolerated at 48 weeks by both younger and older PWH. Despite more comorbidities in PWH > =50, their changes in laboratory outcomes post‐switch were comparable to PWH < 50.