Defendor: Real-world evidence of primary prolonged G-CSF prophylaxis by empegfilgrastim for relative dose intensity compliance in patients with solid tumors- The primary analysis

ABSTRACT

Background: Maintaining relative dose intensity (RDI) of chemotherapy is important to ensure optimal patient outcomes in a variety of solid cancers. RDI < 85% significantly decrease therapy efficiency (including overall survival) in almost solid tumors (ST). Chemotherapy-induced neutropenia (CIN) is the most common adverse event (AE) leading to low RDI. Proper administration of primary G-CSF prophylaxis (PP) allows to achieve optimal therapy efficiency. There are several trials and meta-analyses have shown a superior efficiency prolonged G-CSF vs short G-CSF. This multicenter prospective observational post-registration study of prolonged G-CSF empegfilgrastim (Extimia) was designed to evaluate the RDI of the cytotoxic therapy course under PP by empegfilgrastim in patients (pts) with ST receiving myelosuppressive therapy in the routine clinical practice. Methods: 2000 pts with ST receiving cytotoxic therapy (4-8 cycles per course are allowed) under PP with empegfilgrastim by investigator choice in the routine clinical practice. RDI of therapy course was primary endpoint and presented here for pts who completed the planned regimen. For each agent, both the planned and actual dose intensity were calculated by dividing the total cumulative dose by treatment duration in days. RDI was calculated for each single agent in chemotherapy-based (CTb) regimen and for CTb regimen in total. These descriptive analyses and RDI calculations were performed for the whole CT based regimen (chemotherapeutic agents, molecular target agents, monoclonal antibodies). Funded by JSC Biocad;Defendor Clinical-Trials.gov No NCT04811443. Results: At the data cut-off 1074 pts from 31 Russian sites underwent ≥ one cycle of CTb regimens combined with empegfilgrastim. Distribution of all-cancer types was in line with epidemiology data in Russia. 526 pts completed the planned CT course. 352 (66,9%) of them have at least one of FN risk factor. RDI≥85% were achieved in 492 (93,5%) pts. RDI by key nosology is presented in Tab.1. 118 (22,4%) cases of interval prolongation and/or dose reduction was registered. The main reasons of RDI decrease were personal pts's issues 69 (13,1%), COVID-19 pandemic 26 (4,9%), holidays 9 (1,7%) and others. Neutropenia was in 6 (1,1%) cases as a reason of RDI decrease. Treatment-related AEs of grade 1-2 occurred 12 (2,3%) pts (back pain, ossalgia, myalgia). Conclusions: Thus, PP with prolonged G-CSF empefilgrastim allows effectively maintain RDI in different nosology and treatment groups in pts with ST in the routine clinical practice.