Assessing the Efficacy of Paclitaxel and Olaparib in Comparison to Paclitaxel / Carboplatin Followed by Epirubicin/Cyclophosphamide as Neoadjuvant Chemotherapy in Patients With HER2-negative Early Breast Cancer and Homologous Recombination Deficiency

This is a multicenter, prospective, randomized, open-label phase II study evaluating the efficacy and safety of PO→EC as neoadjuvant treatment of operable and locally advanced breast cancer in patients with HR deficiency. Patients will be randomized to receive * paclitaxel 80 mg/m² iv weekly in combination with olaparib tablets 100 mg (4X25mg) twice daily for 12 weeks (65 patients) or * paclitaxel 80 mg/m² iv weekly in combination with carboplatin AUC 2 iv weekly for 12 weeks (37 patients) both followed by 4 cycles of epirubicin 90 mg/m² and cyclophosphamide 600 mg/m² (EC) either every 3 or every 2 weeks followed by surgery. The control arm was chosen to allow direct comparison with one of the currently considered standard of care regimen.