Comparison of the efficacy, safety and durability of a switch to co-formulated RPV/TDF-TAF/FTC or DTG/ABC/3TC in virologically-suppressed HIV-1-infected patients in a single Italian centre: a cohort data analysis

This study evaluated the efficacy, safety and durability of a switch to co-formulated RPV/TDF-TAF/FTC (RPV-STR) or DTG/ABC/3TC (DTG-STR) in virologically-suppressed HIV-positive patients in a single Italian centre. All HIV-infected ART-experienced patients switching to RPV-STR or DTG-STR with HIV-RNA <50 copies/mL were included. Outcomes were incidence rate and rate ratios for discontinuation due to all causes (DAC), to adverse events (DAE) and to virological failure (VF) after 4 years of follow-up. We included 402 patients (244 on RPV-STR, 158 on DTG-STR). At Year 4 of follow-up, 124 patients (30.8%) discontinued for any cause (71 on RPV-STR, 53 on DTG-STR). Fifteen patients experienced VF [13 (5.3%) on RPV-STR and 2 (1.3%) on DTG-STR; log-rank, P = 0.4413]. Overall, 46 patients (11.4%) had AEs (23 on RPV-STR, 23 on DTG-STR). Nausea/diarrhoea was more frequent with DTG-STR (4.4% vs. 0%) and neurological toxicity with RPV-STR (4.5% vs. 2.5%). The rate of DAC within the first 3 months was significantly higher with DTG-STR (aRR = 5.88, 95% CI 3.20–10.81; P < 0.001); similarly, the discontinuation rate due to AEs was significantly higher with DTG-STR compared with RPV-STR (aRR = 12.89, 95% CI 5.48–30.32; P < 0.001). No difference in VF was observed between the two groups (RR = 0.47, 95% CI 0.10–2.14; P = 0.335). Patients with undetectable viral load who switched to DTG-STR or RPV-STR maintained virological suppression with a low risk of VF. A higher discontinuation rate was observed with DTG-STR compared with RPV-STR, particularly within 3 months from switch.