Analysis of real-world treatment patterns in a matched rheumatology population that continued innovator infliximab therapy or switched to biosimilar infliximab.

Purpose: This study compared treatment patterns of Turkish patients with a diagnosis of rheumatoid arthritis (RA) who were treated with innovator Remicade^® (infliximab [IFX]) and either continued IFX or switched to CT-P13.

Materials and methods: Adult RA patients with ≥1 IFX claim were identified from the Turkish Ministry of Health database. Eligible patients initiated and continued IFX treatment (continuers cohort [CC]) or initiated IFX and switched to CT-P13 (switchers cohort [SC]) during the study period. The initial IFX claim date was defined as the index date. The switch/reference date was defined as the CT-P13 switch date for the SC or a random IFX date during the period of CT-P13 availability for the CC. Cohorts were matched by age, sex, and number of IFX prescriptions during baseline. Patient demographics, discontinuation, and switching were summarized. The baseline period was defined as the period from the index date to the switch/reference date. The follow-up period ranged from the switch/reference date to the end of data availability.

Results: After matching, 697 patients were selected: 605 patients for the CC and 92 patients for the SC. Mean IFX duration for the baseline period was 422 days in the CC and 438 days in the SC. Median time on any infused tumor necrosis factor (TNF) antagonist therapy was 1,080 days in the CC and 540 days in the SC during the study period. During the follow-up period, discontinuation was lower in the CC (CC=33.9% vs SC=87.5%; P<0.001). The mean time to discontinuation was longer in the CC (CC=276 days vs SC=132 days; P<0.001). A switch to another biologic medication during the follow-up period was observed in 19.0% of patients in the CC (n=115) and 81.5% of patients in the SC (n=75; P<0.001).

Conclusion: Treatment patterns differed between patients prescribed IFX and CT-P13. In Turkey, RA patients maintained on IFX had greater treatment persistence (ie, fewer and later discontinuations) than those who initiated IFX and switched to CT-P13.