Adverse events with G-CSF for neutropenia in cancer.

Abstract

e18762 Background: Granulocyte colony stimulating factor (G-CSF) is used to treat chemotherapy-induced neutopenia. This study examined patient characteristics and adverse events (AE) for G-CSF, including biosimilar products, in cancer patients. Methods: Cancer patients new to G-CSF treatment between 7/1/2015 and 11/30/2016 were identified in the MarketScan Database. The first administration of filgrastim (FIL), tbo-filgrastim (TBO), or filgrastim-sdnz (SNDZ) served as the index date. Patients has to be enrolled for ≥ 60 days prior and ≥ 30 days following index. Characteristics were evaluated during the baseline period; AEs were examined over the 30 day follow-up. FIL was the reference group. Results: A total of 5,470 patients (FIL: 4,155, TBO: 771, SNDZ: 544) qualified for the study. Over 4% of FIL use was in pediatric patients compared to < 1% for SNDZ and TBO (p < 0.01); use in elderly patients was similar across the 3 groups. FIL patients were more likely to be male (45%) compared to TBO (40%) and SNDZ (36%) patients (p < 0.01) and were more likely be diagnosed with leukemia and less likely to be diagnosed with breast, gastrointestinal, lymphoma, and respiratory cancers compared to TBO and SNDZ (p < 0.01). There were no significant differences across groups for most AEs (pyrexia, rash, nausea, vomiting, headache, epistaxis, diarrhea, arthralgia, leukocytosis, spleen rupture, acute respiratory syndrome, capillary leak syndrome). TBO patients were more likely than FIL patients to experience cough (5.4 vs 3.4%), dizziness (3.0% vs 1.3%), dyspnea (9.5 vs 7.2%), fatigue (10.2 vs 7.1%), and thrombocytopenia (15.6 vs 12.7%) (p < 0.05). SNDZ patients evidenced lower rates of arthralgia (0.9 vs 3.4%), anemia (18.6 vs 24.8%), fatigue (4.2 vs 7.1%), and thrombocytopenia (7.9 vs 12.7%), but increased rates of dizziness (3.1 vs 1.3%), compared to FIL patients (p < 0.05). Conclusions: Differences observed in demographic and clinical characteristics of the populations receiving the rG-CSFs may be due to the differences in labeled indications such as cancer type or age, reimbursement policies, or provider preferences. Safety profiles were similar with only slight differences in AE rates potentially due to underlying differences in baseline characteristics of the populations.