Background: In Switzerland detailed individual patient data are lacking on trends in health care costs, major drivers of costs, and the contribution of breakthrough innovations, such as direct-acting agents (DAAs) for the treatment of chronic hepatitis C virus (HCV) infection in people with HIV (PWH).

Methods: We linked anonymized data of patients undergoing antiretroviral therapy (ART) or naive patients initiating ART between 2012 and 2017 in the Swiss HIV Cohort Study with claims data of health insurers covering 35% of Swiss residents. Trends in mean annual costs for overall care, ART, and hospitalizations were calculated with an adjustment of costs for censoring. Changes in costs over time in relation to patient characteristics, comorbidities, and treatment of HCV with DAAs were estimated by linear mixed models. Costs were reported in Swiss francs (CHF).

Results: The final linked file contained 1830 individuals from 11 286 participants of the Swiss HIV Cohort Study and 5406 claims records (33.9%). The mean adjusted annual overall cost in 2012 was CHF 24 713 (SD, 14 107) and increased in 2017 by 1.2% to CHF 24 881 (SD, 14 523). Costs for ART contributed by far most to overall costs but decreased over time. Mean costs for hospitalizations increased with annual variation by 7.2% from CHF 8727 (SD, 10 473) in 2012 to CHF 9406 (SD, 9696) in 2017. Mean increases of costs for DAAs for 171 PWH coinfected with HCV (9.4%) were CHF 52 647 (95% CI, 50 862-54 431; P < .01).

Conclusions: Increases in mean total costs for PWH in Switzerland from 2012 to 2017 were small. The contribution of DAAs for the treatment of chronic HCV to overall costs was marginal.