A prospective, multicenter study on stem cell mobilization using EAP regimen as first-line mobilization in patients with multiple myeloma and lymphoma

Abstract Background: The optimal stem cell mobilization strategy in multiple myeloma (MM) and lymphoma remains debatable. We evaluated the efficacy and safety of integrating etoposide, cytarabine, and pegfilgrastim (EAP) regimen in patients with MM and lymphoma. Methods: This phase 2 trial, spanning 12 hospitals in China, enrolled adults aged 18–75 with MM or lymphoma suitable for autologous hematopoietic stem cell transplantation (auto-HSCT). The EAP regimen comprised etoposide 75 mg/m2/day for two days, cytarabine 200 mg/ m2 twice daily for two days, and pegfilgrastim 6 mg on day 6. The primary endpoint was the proportion of patients who attained adequate mobilization (≥2.0´106 CD34+ cells/kg); secondary endpoints included safety and other mobilization efficacy indicators. Results: Between November 2022 and April 2024, 65 patients were enrolled. All patients achieved adequate mobilization, with a median of 14.7×106 CD34+ cells/kg (range: 2.7–47.1) collected. A median of 1.1 apheresis sessions was needed, and 59 patients (90.8%) attained optimal thresholds (≥5.0´106 CD34+ cells/kg). The median time to the first apheresis post-mobilization was 12.5 days, with plerixafor rescue required in 3.1% of the cases. Following post-mobilization, 13.8% of patients developed grade 2–3 infections, while 36.9% required platelet transfusions. In 80.0% of patients who underwent auto-HSCT, the median neutrophil and platelet engraftment times were 10.7 and 11.6 days, respectively. Conclusion: The EAP regimen demonstrates an optimal efficacy and safety profile, making it a promising alternative for stem cell mobilization in MM and lymphoma, particularly in populations with plerixafor-inaccessible.