This study compared the adverse event (AE) profiles of metastatic prostate cancer patients treated with docetaxel-based doublet therapy versus triplet therapy (docetaxel, darolutamide, and ADT). We also aimed to identify risk factors for severe AEs in these regimens

A retrospective, multicenter analysis was conducted, including 359 patients with metastatic castration-sensitive (mCSPC) or castration-resistant prostate cancer (mCRPC) who received docetaxel. Fifty-one patients with mCSPC received triplet therapy. Patient demographics, hematologic and non-hematologic AEs, and risk factors for severe AEs (≥ grade 3) were evaluated. Logistic regression was used to identify predictors of severe AEs.

There were no significant differences in the incidence of ≥ grade 3 neutropenia or febrile neutropenia (FN) between the triplet and doublet therapy groups when stratified by the use of primary prophylaxis with granulocyte colony-stimulating factor (G-CSF). Fatigue was more common in the mCRPC cohort compared to triplet therapy. G-CSF prophylaxis significantly lowered the risk of severe neutropenia (odds ratio [OR] 0.092, p < 0.001) and FN (OR 0.13, p = 0.007).

This is the first real-world comparison of AE profiles in Japanese patients receiving triplet or doublet therapy for mCSPC and mCRPC. No significant differences in severe AEs were observed between the two therapies. G-CSF prophylaxis was crucial in reducing severe neutropenia and FN, enhancing the safety of docetaxel-based treatments.