In spite of multimodal treatment, prognosis of HER2 negative metastatic breast cancers remains poor and innovative targeted therapeutic approaches are urgently warranted. While PARP inhibi-tors as single agent have demonstrated moderate improvement in progression-free survival and quality of life in pre-treated HER2 negative advanced breast cancer patients with germline BRCA mutation, they failed to improve overall survival in this setting. In addition, most of clinical trials testing combinations of chemotherapy and PARP inhibitors have been limited by overlapping hematological toxicities, or have used low dosage PARP inhibitors with short exposure time and with uncertain benefits. The therapeutic strategy selected in this study will be to combine oral capecitabine (2 weeks on, 1 week off, as recommended in monotherapy) and oral niraparib (con-tinuously for a cycle of 21 days). Such an association may increase clinical benefits of PARP inhibitors in germline BRCA mutated HER2 negative advanced breast cancer patients, while po-tentially expanding clinical interest of PARP inhibitors in patients without germline BRCA muta-tion (either with or without HRD).
This study will be to combine oral capecitabine and oral niraparib such thz association may increase clinical benefits of PARP inhibitors in germline BRCA mutated HER2 negative advanced breast cancer patients.