Durability of doravirine/dolutegravir dual combination in a multicentre cohort of elderly people with HIV.

Background: Even though the doravirine/dolutegravir combination is not mentioned by guidelines, real-life data has begun to emerge on its use. We aimed to describe the durability of doravirine/dolutegravir in a multicentre Italian cohort of elderly people with HIV (EPWH).

Methods: We included all EPWH who ever started the doravirine/dolutegravir combination in six Italian centres and were followed up until treatment discontinuation (TD) for any reason (virological failure, death, treatment interruption for other reasons) on 31 March 2024. Descriptive statistics were used to describe the study population; Kaplan-Meier curves and Cox regression analyses were used to estimate incidence and associated predictors of time to TD.

Results: We included 157 people; 61.1% were male, the median age was 59 years (IQR: 55-64), 75.2% had multimorbidity, 38.9% were on polypharmacy, and 91.1% had HIV-RNA of <50 copies/mL. No genotype resistance test was available for 19.4% of people who started doravirine/dolutegravir. The main reasons for starting doravirine/dolutegravir were high cardiovascular risk (51.6%), simplification (52.9%) and drug-drug interactions (25.5%). During a median follow-up of 27.85 (IQR: 22.92-31.79) months, 8 (5.1%) participants experienced TD (2 toxicities, 2 virological failures, 2 switches to long-acting drugs, 1 death and 1 transferred). The incidence of TD was 2.27 per 100 person-years of follow-up. Multivariable Cox regression analyses did not show any factors as predictors of TD.

Conclusions: In this multicentre cohort of EPWH with clinical complexity, the doravirine/dolutegravir combination showed good durability over time. TD probability was very low, and no significant factors seem to predict it, likely due to the limited number and heterogeneity of cases of TD.