P-353. Ten Years Results on the Effectiveness and Safety of DTG+3TC as a Switch Regimen in a Multicenter Cohort

TL;DR

This study shows that switching to DTG+3TC is effective and safe for up to 10 years in people with HIV, with minimal side effects and improved immune markers.

Contribution

Long-term (10-year) real-world evidence on the effectiveness and safety of DTG+3TC as a switch regimen in HIV treatment.

Findings

Estimated probabilities of maintaining virological suppression at 240 and 480 weeks were 96.2% and 92.8%, respectively.

Significant improvements in CD4+ count and CD4/CD8 ratio were observed after 240 weeks.

Metabolic parameters like cholesterol and triglycerides showed significant improvement at both 240 and 480 weeks.

Abstract

We aim to assess the efficacy, safety and tolerability of DTG+3TC as a switch regimen after 10 years of its introduction in clinical practice.

An observational study was conducted with virologically suppressed PLWH switching to DTG+3TC in a multicenter cohort. Exclusion criteria included HBsAg+ status and M184V resistance mutation. We employed Kaplan-Meyer survival analysis for virological failure (VF) and treatment discontinuation (TD), Cox-regression for VF or TD predictors, and linear mixed models for immunological and metabolic parameter changes.

We enrolled 2430 PLWH: 1587 (65.3%) were males, with a median age of 54.5 yrs. Full population characteristics are shown in Table1.

During 9199 PYFU, we observed 82 VF (0.9 per 100 PYFU); no emergent resistance mutations were registered among VF. Estimated probabilities of maintaining virological suppression (VS) at 240 and 480 wks were 96.2% and 92.8%, respectively. At a multivariate analysis, a history of at least one previous VF before switch (vs no event, aHR 2.09, p=0.005) and a time of VS < 8 years before switch (vs VS > 8 years, aHR 1.82, p=0.021) were significantly associated with a higher risk of VF.

During 9287 PYFU, we observed 339 TD (3.7 per 100 PYFU). Estimated probabilities of maintaining DTG/3TC were 83.8% at 240 wks and 79.4% at 480 wks. Discontinuations for toxicity were 78 (23.0% of all TD), with CNS toxicity accounting for 25 cases. Other frequent reasons for TD were: switch to CAB+RPV (64, 18.9%) and treatment intensification (32, 9.4%).

At a multivariate analysis, we found that a HIV-RNA peak > 500.000 cps/mL (aHR 1.55, p=0.006) and the presence of HBcAb (aHR 1.60, p=0.002) were significantly associated with a higher risk of TD; meanwhile, the presence of DTG in the ARV regimen before switch, (aHR 0.51, p=0.001) was inversely correlated with TD risk.

After 240 weeks, we registered a significant improvement in both CD4+ count (+59, p < 0.001) and CD4/CD8 ratio (+0.1, p < 0.001).

As to metabolic parameters, we observed significant improvement in total cholesterol, tryglicerides and HDL cholesterol at both 240 and 480 weeks (p < 0.02 for all).

We assessed the efficacy and safety of DTG+3TC in the long term while also showing neutral impact on metabolic parameters.

All Authors: No reported disclosures

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