Clinical use and effectiveness of dolutegravir and lamivudine: a long-term, real-world, retrospective study

Real-World Effectiveness and Tolerability of Dolutegravir and Lamivudine 2-Drug Regimen in People Living with HIV: Systematic Literature Review and Meta-Analysis

INTRODUCTION

Dolutegravir (DTG) + lamivudine (3TC) demonstrated high rates of virologic suppression (VS) and low rates of virologic failure (VF), discontinuation, and drug resistance in randomized trials. Real-world evidence can support treatment effectiveness, safety, and tolerability in clinical practice and aid in treatment decisions.

METHODS

A systematic literature review (SLR) was conducted to identify studies using DTG + 3TC (January 2013-March 2024). Studies were screened to include observational studies reporting 48- or 96-week on-treatment VS, VF, or discontinuation outcomes; proportions of individuals with each outcome at each time point were estimated using random- and common-effects models.

RESULTS

Of 249 SLR-identified publications, 43 reported consistently defined outcomes of interest at comparable time points, representing 1480 individuals naive to antiretroviral therapy (ART) and 12,234 individuals with prior ART experience. At weeks 48 and 96, respectively, estimated proportions (95% CIs; random-effects model) with on-treatment VS were high (naive to ART, 0.964 [0.945-0.979] and 0.902 [0.816-0.966]; prior ART, 0.966 [0.950-0.980] and 0.971 [0.946-0.990]), with low estimated proportions experiencing VF (naive to ART, 0.001 [0.000-0.013] and 0.001 [0.000-0.008]; prior ART, 0.009 [0.005-0.015] and 0.015 [0.007-0.024]) and discontinuations for any reason (naive to ART, 0.052 [0.019-0.097] and 0.130 [0.084-0.183]; prior ART, 0.067 [0.042-0.098] and 0.084 [0.047-0.130]). Across identified studies (> 44,000 unique individuals), those reporting resistance outcomes at VF/blip (regardless of emergence) detected integrase strand transfer inhibitor (INSTI) mutations in 0 of 2346 individuals naive to ART and 0.02% (4/20,060) of individuals with prior ART experience (S147G, R263K, G118R + E138K, T66A + G118R + E138K); additionally, N155H was reported in an individual using DTG + 3TC with unknown baseline ART status.

CONCLUSION

Overall treatment outcomes in real-world settings confirm the efficacy, tolerability, and high barrier to resistance seen in phase 3 trials across diverse populations, including those naive to ART or with prior ART experience.

Virologically suppressed switch to Dolutegravir/Lamivudine 2-Drug regimen versus switch to commonly prescribed 3-Drug regimens in the United States

BACKGROUND

Two-drug regimens (2DRs) have been introduced in recent years to potentially reduce antiretroviral therapy (ART) toxicities and drug-drug interactions while demonstrating comparable efficacy to three-drug regimens (3DRs) for people with HIV (PWH). The objective of this study was to compare the real-world effectiveness and durability of a single-tablet 2DR of dolutegravir/lamivudine (DTG/3TC) with that of commonly prescribed 3DRs in ART-experienced, virologically suppressed PWH during the first 24 months of DTG/3TC availability in the United States.

METHODS

Virologically suppressed (viral load [VL] < 200 copies/mL) adult PWH initiating DTG/3TC 2DR, bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF), or a DTG-based 3DR between 01MAY2019 and 31OCT2020 were identified in the OPERA® cohort and followed through 30APR2021. Univariate Poisson regression (incidence rates) and marginal structural Cox proportional hazards models with inverse probability of treatment weights (hazard ratios) were used to quantify relationships between regimen type and confirmed virologic failure (2 consecutive VLs ≥ 200 copies/mL) or regimen discontinuation. Reasons for discontinuation were examined.

RESULTS

A total of 8,037 ART-experienced, virologically suppressed PWH met the inclusion criteria and switched to DTG/3TC (n = 1,450), BIC/FTC/TAF (n = 5,691), or a DTG-based 3DR (n = 896). Incidence rates of confirmed virologic failure were low for all groups, at 0.66 (DTG/3TC), 0.84 (BIC/FTC/TAF), and 1.78 (DTG 3DR) per 100 person-years (py). Compared to DTG/3TC, only the DTG 3DRs were associated with a statistically significant increased hazard of confirmed virologic failure (hazard ratio: 5.21, 95% confidence interval: 1.85, 14.67). Discontinuation rates per 100 py were highest in the DTG 3DR group (24.90), followed by the DTG/3TC group (17.69) and the BIC/FTC/TAF group (8.30). Regardless of regimen, discontinuations were infrequently attributed to effectiveness (VL ≥ 200 copies/mL; 4%) or tolerability (adverse diagnoses, side effects, or lab abnormalities; 6%).

CONCLUSIONS

Among virologically suppressed PWH initiating a new regimen, few individuals experienced virologic failure in real-world clinical care. While rates of regimen discontinuation were high, most discontinuations could not be attributed to a lack of virologic control or poor tolerability. These findings suggest that DTG/3TC is an effective option for ART-experienced, virologically suppressed PWH.

Switching to Dolutegravir/Lamivudine Two-Drug Regimen: Durability and Virologic Outcomes by Age, Sex, and Race in Routine US Clinical Care

Purpose

Two-drug regimens (2DR) may address drug-drug interactions and toxicity concerns. Dolutegravir/lamivudine (DTG/3TC) 2DR was approved in the US for both treatment-naïve and treatment-experienced individuals with a viral load <50 copies/mL. This study describes real-world DTG/3TC 2DR treatment outcomes among treatment-experienced individuals, stratified by age, sex, and race.

Methods

From the OPERA® cohort, people with HIV with a viral load <50 copies/mL who switched from a commonly used three-drug regimen to DTG/3TC 2DR as per the label between April 8, 2019 and April 30, 2021 were included. Incidence rates (Poisson regression) for loss of virologic control (first viral load ≥50 copies/mL), confirmed virologic failure (2 viral loads ≥200 copies/mL or discontinuation after 1 viral load ≥200 copies/mL), and DTG/3TC 2DR discontinuation were estimated overall and stratified by age, sex, and race.

Results

The 787 individuals included were followed for a median of 13.6 months (IQR: 8.2, 22.3). Confirmed virologic failure occurred in ≤5 individuals. Loss of virologic control occurred at a rate of 14.0 per 100 person-years (95% CI: 11.7, 16.8). DTG/3TC 2DR discontinuation occurred at a rate of 17.5 per 100 person-years (95% CI: 15.0, 20.3); 4% discontinued for treatment-related reasons (viremia, adverse diagnosis, side effect, lab abnormality). For all outcomes, incidence rates were comparable across strata of age, sex, and race.

Conclusion

This descriptive study demonstrates that DTG/3TC 2DR is an effective and well-tolerated treatment option for people with HIV with a viral load <50 copies/mL at switch, regardless of their age, sex, or race.

Dolutegravir/Lamivudine versus Tenofovir Alafenamide/Emtricitabine/Bictegravir as a Switch Strategy in a Real-Life Cohort of Virogically Suppressed People Living with HIV

BACKGROUND

The aim of the study is to evaluate the effectiveness, safety, and tolerability of a two-drug regimen (2-DR) dolutegravir/lamivudine (DTG/3TC) versus a three-drug regimen (3-DR) tenofovir alafenamide/emtricitabine/bictegravir (TAF/FTC/BIC) in a real-life cohort of HIV-1 virologically suppressed treatment-experienced (TE) people living with HIV (PLWH).

METHODS

This was a single-center, retrospective, observational study analyzing adult TE PLWH who started the 2-DR or 3-DR between January 2018 and January 2023. All PLWH with a viral load (VL) <50 copies/mL at the time of switching, and a follow-up of more than 6 months or interruption of treatment at any time, were included.

RESULTS

A total of 324 PLWH were included; of these, 110 (34%) were on the 2-DR and 214 (66%) were on the 3-DR. Most patients remained on therapy in both groups (93.6% 2-DR versus 90.2% 3-DR) and, at the last control, 99.1% achieved VL < 50 copies/mL with the 2-DR versus 97.2% with the 3-DR (p = 0.260). No virological failures occurred in either group. Adverse events occurred in a few cases: four (3.6%) in the 2-DR group and five (2.3%) in the 3-DR group (p = 0.500). The median follow-up-time was 19.6 months for the 2-DR and 27.5 months for the 3-DR.

CONCLUSION

Our study shows a similar effectiveness and safety profile in virologically suppressed PLWH switching to DTG/3TC or TAF/FTC/BIC.