Safety and Effectiveness Analyses of Dolutegravir/Lamivudine in Patients with HIV: 2-Year Report of Post-Marketing Surveillance in Japan

INTRODUCTION: Since 2019, for the first time, a two-drug regimen with dolutegravir/lamivudine (DTG/3TC) has been recommended for HIV treatment as initial and subsequent therapy in the international guidelines. However, safety and efficacy data of DTG/3TC in Japanese people living with HIV (PLHIV) in clinical trials are limited and have not been evaluated in clinical practice. In this report, we evaluated safety and effectiveness of DTG/3TC in Japanese PLHIV through post-marketing surveillance. METHODS: Post-marketing surveillance was conducted to evaluate the real-world safety and effectiveness of DTG/3TC in Japanese PLHIV. One hundred ninety-seven patients who received oral DTG 50 mg/3TC 300 mg as a single-tablet fixed-dose combination regimen (STR) were registered in clinical practice. The safety was evaluated by incidence of adverse drug reactions (ADRs). The effectiveness was evaluated by plasma HIV RNA and peripheral CD4(+) cell counts. RESULTS: This is a 2-year (from 2020 to 2022) report of approximately 6 years of survey, and 187 patients were registered from 21 Japanese sites. The number of antiretroviral therapy (ART)-experienced patients was 178, and > 60% of their previous antiretrovirals (ARVs) were DTG/abacavir (ABC)/3TC. There were only nine ART-naïve patients. Four of 178 ART-experienced patients (2.25%) reported ADRs, and 1 serious ADR of syphilis was reported. There was no clear causal relationship between DTG/3TC and the ADRs. Plasma HIV RNA and peripheral CD4(+) cell counts maintained the pre-DTG/3TC level in ART-experienced patients. CONCLUSION: No new clinical concerns of safety and effectiveness were identified in Japanese ART-experienced PLHIV treated with DTG/3TC. We could not discuss the safety and effectiveness in ART-naïve patients because of the small sample size.