A Retrospective Analysis of Prophylactic G-CSF Biosimilar and Originator Administrative Claims over Time Among Patients with Non-Hodgkin Lymphoma

Objectives: To characterize G-CSF product use including product switching and uptake and commonly used chemotherapy treatment regimens among patients diagnosed with non-Hodgkin Lymphoma (NHL) in the Biologics and Biosimilars Collective Intelligence Consortium's (BBCIC) Distributed Research Network (DRN). Methods: Retrospective analysis of patients aged 20 years and older with NHL who received any prophylactic G-CSF, defined as before day 2 of the first 2 cycles of chemotherapy, classified as low, intermediate, or high risk for febrile neutropenia per NCCN guidelines in 2015-2019 based on administrative claims at 4 Research Partner sites: Aetna (CVS Health), Harvard Pilgrim Health Care Institute, HealthCore (Anthem), and HealthPartners Institute. Results: A total of 2,571 patients were included; 1,462 (57%) were male. Most patients (n=1890, 73%) were 50-79 years; 352 (14%) 20-49 years, and 329 (13%) 80+ years. Of 2,094 (81%) patients who received high-risk chemotherapy, 1,919 (92%) received pegfilgrastim, 71 (3%) pegfilgrastim-cbqv, 49 (2%) pegfilgrastim-jmdb, 21 (<1%) filgrastim, 20 (<1%) filgrastim-sndz, and 14 (<1%) tbo-filgrastim or a combination of products. Of 358 (14%) patients who received intermediate-risk chemotherapy, 301 (84%) received pegfilgrastim, 20 (6%) filgrastim, 12 (3%) filgrastim-sndz, 11 (3%) pegfilgrastim-jmdb, 7 (2%) received pegfilgrastim-cbqv, 5 (1%) tbo-filgrastim, and 2 (<1%) combination. An additional 119 (5%) patients received low risk chemotherapy; of those, 92 (77%) received pegfilgrastim, 13 (11%) filgrastim, 5 (4%) received tbo-filgrastim, 5(4%) received pegfilgrastim-cbqv, and 4 (3%) received filgrastim-sndz. In 2015, the year filgrastim-sndz became available, 484 (97%) patients received pegfilgrastim, 9 (2%) received filgrastim, and 5 (1%) received tbo-filgrastim. In 2019, the first full year of pegfilgrastim-cbqv and pegfilgrastim-jmdb biosimilar availability, 353 (69%) received pegfilgrastim, 81 (16%) pegfilgrastim-cbqv, 56 (11%) pegfilgrastim-jmdb, 11 (2%) filgrastim-sndz, 8 (1.5%) filgrastim, and <1% received tbo-filgrastim or a combination of products. The most common chemotherapy regimens included cyclophosphamide/doxorubicin/vincristine/rituximab (n=1,304), bendamustine/rituximab (n=469), cyclophosphamide/rituximab (n=119), cyclophosphamide/doxorubicin/vincristine (n=105), rituximab (n=101), doxorubicin/vinblastine (n=91), and cyclophosphamide/doxorubicin/etoposide/vincristine/rituximab (n=46). Overall, 141 (5%) developed FN and nearly 15% (n=378) received an antibiotic during the first cycle of chemotherapy. Of the 2,390 (93%) who received a G-CSF product in the second cycle, most received the same product, specifically 94% continued to receive pegfilgrastim, 90% pegfilgrastim-cbqv, 98% pegfilgrastim-jmdb, 78% filgrastim, 100% tbo-filgrastim, and 64% filgrastim-sndz. Conclusions: Most NHL patients received high FN risk chemotherapy with cyclophosphamide, doxorubicin, vincristine, and rituximab and pegfilgrastim. Pegfilgrastim biosimilar uptake occurred following market availability. Within each G-CSF product, most patients received the same product during the second cycle of chemotherapy rather than switching products.