Efficacy and Safety of Switching to Dolutegravir/Lamivudine in Virologically Suppressed People Living with HIV-1 Aged Over 65 Years.

Clinical trials of dual regimen dolutegravir/lamivudine (DOL/3TC) demonstrated potent efficacy and favorable safety in both antiretroviral therapy-naïve and -experienced patients, but data on older people are lacking. We aimed to evaluate virological efficacy and safety of DOL/3TC in suppressed older patients over a 12-month period. We performed a retrospective cohort study evaluating people living with HIV (PLWHIV) aged ≥65 years at our HIV Clinic who were switched to DOL/3TC. Eligible patients had baseline HIV-1 RNA <20 copies/mL, and no previous virological failures or known resistance mutations for lamivudine or dolutegravir. Inclusion criteria were met by 72 patients: 59 were men, median age was 69.2 years, and one or more comorbidities were present in 89% of patients. The most common reason for switch was simplification, followed by drug-drug interactions (DDIs) and toxicities. After 12 months, 64 (88.9%, by the intention-to-treat analysis) patients maintained HIV-1 RNA <20 copies/mL, and reasons for treatment failure were virological failure in three cases, adverse events in three, and missing data in two. Genotype resistance testing showed no resistance mutations for lamivudine or dolutegravir in subjects with virological failure. The number of potential DDIs decreased from 92 to 12 after switching to DOL/3TC, and a significant reduction in median total and low-density lipoprotein cholesterol was reported, while median change in body weight was not significant. In this real-life cohort, switching to DOL/3TC was associated with maintenance of virological control and good tolerability among persons aged >65 years, supporting use of this dual regimen in older PLWHIV.