Efbemalenograstim alfa for prophylaxis in non–small cell lung cancer patients patients with chemotherapy-induced febrile neutropenia: A randomized, multicenter, exploratory clinical trial.

Abstract

8657 Background: Neutropenia is a common dose-limiting chemotherapy toxicity, with its severity and duration impairing therapeutic efficacy. In NSCLC management, chemotherapy regimens with high risk febrile neutropenia (FN) are relatively uncommon. However, real-world data show suboptimal prophylactic granulocyte colony-stimulating factor (G-CSF) use in intermediate risk FN patients with additional risk factors. This study evaluated efbemalenograstim alfa's efficacy and safety in maintaining absolute neutrophil count (ANC) during chemotherapy cycles in such NSCLC patients. Methods: This was a randomized, multicenter, exploratory clinical trial (NCT06143735) enrolling NSCLC patients receiving intermediate risk FN chemotherapy with additional risk factors. Eligible patients were randomized 2:1 into two groups: primary prophylaxis group (Group A) received subcutaneous efbemalenograstim alfa (20 mg) 48±4 h post-each chemo cycle starting from Cycle 1; secondary prophylaxis group (Group B) initiated treatment only upon grade ≥3 neutropenia (per CTCAE v5.0) in the prior cycle. All patients completed at least four cycles of platinum-based chemotherapy. The primary endpoint was the incidence of grade ≥3 neutropenia in Cycle 1 between the two strategies. Secondary endpoints included FN incidence, grade ≥3 neutropenia in subsequent cycles, and the occurrence of adverse events (AEs) or serious adverse events (SAEs). Results: As of Dec 31, 2025, 99 patients were enrolled; 93 (median age: 69 years; 61.3% with ECOG 0–1; 90.3% male) received ≥1 platinum-based chemo cycle; 83 received ≥1 efbemalenograstim alfa dose. Specifically, 61 patients were assigned to Group A and 32 to Group B (n = 93). In the first treatment cycle, the incidence of grade ≥3 neutropenia was 19.7% (12/61) in Group A vs. 50.0% (16/32) in Group B, representing a relative risk reduction (RRR) of 60.6% (absolute risk reduction: 30.3%; p = 0.002). Across all treatment cycles, the cycle-specific cumulative incidence of grade ≥3 neutropenia was 16.2% (32/198) in Group A vs. 25.6% (32/125) in Group B (p = 0.0382). FN occurred in 2 patients in both groups. Regarding safety, the most common adverse events (AEs) were hematological toxicities in both groups, with a numerically lower incidence of anemia, leukopenia, neutropenia, and thrombocytopenia in Group A than in Group B. Grade ≥3 AEs (52.5% vs. 43.8%, p = 0.514) and efbemalenograstim alfa-related treatment-emergent adverse events (TRAEs, 31.1% vs. 22.7%, p = 0.587) did not differ significantly. Pain-related TRAEs (mainly ankle pain and neuropathic pain) were reported in only 6 patients (7.2%) overall, with most being grade 1–2 per CTCAE v5.0 criteria. Conclusions: Efbemalenograstim alfa effectively reduces the incidence of chemotherapy-induced neutropenia and presents a favorable safety profile. Clinical trial information: NCT06143735 .