Real-world clinical and laboratory changes after switching to two-drug regimen in HIV-suppressed individuals:...

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.

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.

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.

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.