Comparative effectiveness of pegfilgrastim biosimilars vs originator for prevention of febrile neutropenia: A retrospective cohort study

BACKGROUND: Real-world evidence on the comparative effectiveness of pegfilgrastim biosimilars compared with the originator product is limited. OBJECTIVE: To compare the risk of febrile neutropenia (FN) among users of pegfilgrastim biosimilars (pegfilgrastim-jmdb and pegfilgrastim-cbqv) and the originator product. METHODS: A retrospective cohort study was conducted using 2019 IBM MarketScan databases to assess comparative effectiveness of pegfilgrastim originator and biosimilars for prevention of FN among patients receiving myelosuppressive chemotherapy. Patients with cancer, including breast, lung, colorectal, esophageal and gastric, pancreatic, prostate, ovarian, and non-Hodgkin lymphomas, initiating myelosuppressive chemotherapy courses were selected. We further selected patients who used pegfilgrastim originator and biosimilars within 3 days of chemotherapy completion. FN-associated hospitalizations were measured by International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes. After 1:1 propensity score matching, we used equivalence (with a margin of 6%) hypothesis tests to compare FN-related hospitalization risk in the first cycle and across all cycles between biosimilars and originator users. RESULTS: A total of 2,045 patients were included, of which 445 (21.8%) used pegfilgrastim-jmdb, 636 (31.1%) used pegfilgrastim-cbqv, and 964 (47.1%) used pegfilgrastim originator. After matching, 13 out of 445 originator users and 17 out of 445 pegfilgrastim-jmdb users developed FN after the first chemotherapy cycle (risk difference was 0.9%; P < 0.001 for equivalence test indicating statistical equivalence). After matching, 14 out of 633 originator users and 16 out of 633 pegfilgrastim-cbqv users developed FN (risk difference was 0.32%; P < 0.001 for equivalence test indicating statistical equivalence). Results across all cycles (including the first cycle) were consistent with that in the first cycle. CONCLUSIONS: In this real-world study of patients with cancer receiving myelosuppressive chemotherapy, there was no difference in FN risk between patients receiving pegfilgrastim originator and biosimilars in the first cycle and across all cycles. These results add further to the current evidence on pegfilgrastim biosimilars and support wider adoption of pegfilgrastim biosimilars among payers, providers, and patients. Future studies assessing the tolerability, side effects, and other safety issues of pegfilgrastim biosimilars are needed.