ABSTRACT: Objective:We evaluated trends and population effectiveness (tolerability, HIV suppression) of current combination antiretroviral therapy (cART) regimens mindful of treatment guidelines. Method:Trend analyses included 18 017 person-visits (1457 men) on cART during 2008-2017 in the Multicenter AIDS Cohort Study. Effectiveness analyses of current regimens used 3598 person-visit-pairs (745 men) on cART in 2014-2017. Inverse-probability-of-treatment-and-censoring weighted Poisson regression with robust variances was used to evaluate the association between regimens and switching, adherence and HIV RNA <20 copies/mL. Results:Integrase strand transfer inhibitor (INSTI)-based regimen usage has increased since 2008. Almost 90% of cART initiators started with INSTI-cART in 2016-2017; cART adherence was stable around 90% and 83%-85% suppressed virus (<20 cp/mL). Commonly used regimens in 2014-2017 contained disoproxil fumarate/emtricitabine (TDF/FTC) backbone with efavirenz (EFV, n = 1161 person-visits), elvitegravir/cobicistat (EVG/c, n = 551), rilpivirine (RPV, n = 492), darunavir/ritonavir (DRV/r, n = 351), or atazanavir (ATV)/r (n = 333). Others were dolutegravir/abacavir/lamivudine (DTG/ABC/3TC, n = 401) and EVG/c/tenofovir alafenamide/FTC (EVG/c/TAF/FTC, n = 309). Compared to EFV/TDF/FTC users, ATV/r+TDF/FTC users switched more (rate ratio [RR] = 1.80, 95% confidence interval (CI), 1.17-2.76), while those on DTG/ABC/3TC (RR [95% CI] = 0.16 [0.08-0.31]) or EVG/c/TAF/FTC (RR [95% CI] = 0.12 [0.06-0.27]) switched less. The rate of suppressed HIV RNA was 15% (95% CI, 2%-26%) lower among younger EVG/c/TDF/FTC users and 18% (95% CI, 3%-34%) higher in older DRV/r+TDF/FTC users; adherence did not differ by regimen. Conclusions:Consistent with guidelines, recent cART initiators started with INSTI-cART, which was associated with less switching early after initiation. Factors beyond those studied here, such as need for salvage therapy, unique personal characteristics, drug interactions, and cost may influence treatment decisions.