Efficacy and safety of mecapegfilgrastim in preventing neutropenia during concurrent chemoradiotherapy.

Abstract

e24119 Background: Current guidelines recommend prophylactic use of granulocyte colony-stimulating factor (G-CSF) to reduce the incidence, duration, and severity of chemotherapy-induced neutropenia. We evaluated the efficacy and safety of mecapegfilgrastim, a long-acting G-CSF, in preventing neutropenia for solid tumor patients during concurrent chemoradiotherapy (CCRT). Methods: In this multicenter, open-label, randomized controlled trial, patients with lung, esophageal, or cervical cancers, and an ECOG performance status of 0-2 were randomized 1:1 to the study or control group. Both groups received standard CCRT with two 21-day cycles of taxanes and platinum-based chemotherapy. In the study group, mecapegfilgrastim 6 mg was administered 24 hours after chemotherapy for each cycle, whereas the control group received no prophylaxis for neutropenia. Short-acting G-CSF was administered if neutrophil counts fell below 2.0×10^9/L. Treatment-emergent adverse events (TEAEs) were monitored for 2 cycles and graded per CTCAE v5.0. The primary endpoint was the incidence of grade 3/4 neutropenia during CCRT. Results: From Apr 2022 to Dec 2023, 97 patients were enrolled: 48 in the study group and 49 in the control group. The median age was 59 years (range 51-71) in the study group and 60 years (range 34-71) in the control group. Baseline characteristics were balanced between two groups. Eleven patients (22.9%) in the study group experienced grade 3/4 neutropenia, compared to 27 (55.1%) in the control group (nominal p= 0.002). Three patients (6.3%) in the study group and 2 (4.1%) in the control group developed febrile neutropenia (FN). For 18 lung cancer patients, none of the study group experienced grade 3/4 neutropenia, while 2 patients (25.0%) in the control group did. FN was not reported in either group. Among 40 esophageal cancer patients , grade 3/4 neutropenia was observed in 4 patients (21.1%) of the study group, compared to 12 (57.1%) of the control group, with one case of FN in each group. For 39 gynecological cancer patients, grade 3/4 neutropenia occurred in 7 patients (36.8%) in the study group and 13 (65.0%) in the control group. Two patients of the study group and 1 of the control group developed FN. Short-acting G-CSF was required in 18 patients (37.5%) of the study group and 33 (67.4%) of the control group. TEAEs were reported in 27 patients (56.3%) of the study group and 41 (83.7%) of the control group. Notably, grade ≥3 TEAEs were reported in 21 patients (43.8%) of the study group and 30 (61.2%) of the control group, maily including hematologic toxicities like neutropenia, thrombocytopenia, and lymphocytopenia. Serious TEAEs were reported in 1 patient (2.1%) of the study group and 2 (4.1%) of the control group. One patient (2.1%) in the study group discontinued treatment due to TEAEs. Conclusions: Prophylaxis with mecapegfilgrastim reduced the incidence of grade 3/4 neutropenia during CCRT, with good safety. Clinical trial information: ChiCTR2200058551.