Binational phase 3 trial of biweekly versus triweekly cabazitaxel for metastatic castration-resistant prostate cancer in older patients

Many patients aged 65 years or older with metastatic castration-resistant prostate cancer (mCRPC) are denied taxane chemotherapy because this treatment is considered unsuitable. The phase 3 CABASTY trial, at 25 centers in France and Germany, compared biweekly cabazitaxel 16 mg/m² (biweekly CBZ16) plus G-CSF at each cycle versus triweekly cabazitaxel 25 mg/m² (triweekly CBZ25) plus G-CSF for mCRPC in 196 heavily pretreated patients aged 65 years or older. Biweekly CBZ plus G-CSF significantly reduced by 12-fold the incidence of grade 3 or higher neutropenia and/or neutropenic complications compared with triweekly CBZ25. There were no significant differences between the two groups for overall survival or radiological progression-free survival. The authors conclude that biweekly CBZ16 plus G-CSF should be offered to patients 65 year or older with mCRPC, for whom standard cabazitaxel regimens are unsuitable.