Abstract OT3 01 02: PARTNERING/PARTNER: Phase II sub study to establish if the addition of combinations of new agents (olaparib, cell cycle and immune checkpoint inhibitors …

Background:In patients with TNBC, following standard neoadjuvant chemotherapy, residual disease (RD) is correlated with poor prognosis and 50% relapse within 5 years [1]. PARTNER is a neoadjuvant clinical trial which randomises TNBC and gBRCAm patients to carboplatin and paclitaxel +/- olaparib followed by anthracycline-based chemotherapy. Patients with RD after neoadjuvant treatment in this trial also face poorer survival outcomes, due to the paucity of treatment options. PARTNERING, develops a new strategy using novel agent combinations as an alternative pathway for patients with RD within the PARTNER trial.Methods: PARTNERING is a phase II open label, sub-study with a two-stage Simon design with biomarker guided treatment cohorts open only to patients in the PARTNER trial. A maximum of 15 patients will be included in each cohort. Patients with RD > 10% tumour cellularity (TC) on biopsy …