OBJECTIVES: Describe treatment patterns of people with HIV (PWH) initiating INSTI-containing antiretroviral (ARV) treatments in a real-world US setting.

METHODS: Prescription claims data from the IQVIA Longitudinal Access and Adjudication Dataset (LAAD) were utilized. Individuals in the dataset between 01 January 2018 to 31 July 2023 were included if they had HIV-1, were ≥ 18 years old with known sex, had ≥ 1 pharmacy claim for an ARV with a newer INSTI-based regimen (CAB+RPV, DTG/ABC/3TC, BIC/FTC/TAF, DTG/3TC, DTG+FTC/TDF, DTG+FTC/TAF) from 01 January 2020 to 31 December 2022 (index date), and were continuously treated with a complete ARV regimen for at least 6 months before initiating an INSTI-based therapy. Persistence was measured from the index INSTI therapy until treatment switch to a new ARV within a 60-day treatment gap, and was assessed via Cox proportional hazard models, accounting for age, sex, geographic region, insurance type, polypharmacy, immunosuppressive therapy, Charlson Comorbidity Index (CCI), and index year.

RESULTS: Among 29,348 PWH initiating therapy (mean age 53.7 years, 23.2% female, 58.7% commercially insured, mean CCI 0.375, 46.6% from the South), 8.3% switched to a new therapy during follow-up (9.4% within 90 days). Likelihood of switching was higher for PWH with female sex (p=0.004), Medicaid coverage (p<0.001), and with higher CCI scores (p=0.05). In adjusted models, risk of treatment switch was higher for all other regimens compared to BIC/FTC/TAF: Hazard Ratio (HR) 14.5 (10.9, 19.2) for DTG+FTC/TDF, HR 4.8 (4.0, 5.7) for DTG+FTC/TAF, HR 4.2 (3.5, 5.0) for DTG/ABC/3TC, HR 2.9 (2.5, 3.4) for CAB+RPV, and HR 1.3 (1.1, 1.4) for DTG/3TC. Sensitivity analyses using a 90-day period for switching were consistent with the base case.

CONCLUSIONS: Nearly one in 10 treatment-experienced PWH experienced a secondary switch in therapy. PWH initiating BIC/FTC/TAF were significantly less likely than those starting other INSTI-based regimens to subsequently switch.