Treatment Persistence and Switch Among Medicare-Insured People with HIV and Gaps in Care

Adherence to antiretroviral therapy (ART) is crucial for people with HIV (PWH) to maintain health. The Medicare program insures a substantial proportion of PWH in the United States; however, few studies have evaluated ART treatment patterns in this population. This study described treatment persistence and switch patterns among Medicare-insured PWH with low ART adherence or significant treatment gaps prior to re-initiating ART.

A retrospective cohort study was conducted using data from Medicare Fee-For-Service and Medicare Advantage from January 2017 to December 2022. PWH aged ≥ 18 years with documented treatment experience receiving an index ART regimen of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF), dolutegravir/lamivudine (DTG/3TC), dolutegravir/abacavir/lamivudine (DTG/ABC/3TC), or multi-tablet regimens (MTRs; dolutegravir + emtricitabine/tenofovir alafenamide [DTG + F/TAF] or dolutegravir + emtricitabine/tenofovir disoproxil fumarate [DTG + F/TDF]) were included. Study groups of interest included PWH with low adherence (defined as a proportion of days covered [PDC] < 85%) and PWH who had initiated index ART after a ≥ 90-day gap. Treatment nonpersistence (discontinuation or switch) and switch outcomes were evaluated using Kaplan-Meier curves and Cox proportional hazards models.

Of 30,205 treatment-experienced PWH, 6140 had low adherence on the index regimen and 7227 had significant treatment gaps prior to re-initiating ART. In both groups, risk of treatment nonpersistence was significantly lower for PWH indexed on B/F/TAF versus DTG/ABC/3TC and MTRs but similar for DTG/3TC. Risk of treatment switch was lower for those indexed on B/F/TAF versus all other ART regimens evaluated (P < 0.01).

Among Medicare-insured PWH with low adherence or significant gaps in care, those receiving B/F/TAF had a lower risk of switch compared with other ART regimens. Optimizing ART selection to improve persistence and reduce treatment switching remains an important consideration.