The rationale for integrating immunotherapy with chemotherapy is based on preclinical studies, which have shown, that chemotherapy induces immunogenic cell death leading to increased recognition of the tumor by the immune system. Carboplatin is shown to inhibit PD-L2 expression, thereby limiting immunosuppression by both dendritic cells and tumor cells. Paclitaxel decreases the percentage of CD4+ and FoxP3+ regulatory T cells (Tregs) and reduces their cytokine production without disrupting the function of its effector counterpart (CD4+ and FoxP3 effector T (Teff) cells). Several trials have shown effect of checkpoint inhibition following chemotherapy and radiotherapy, most notably in the PACIFIC trial in stage III NSCLC [63]. We therefore hypothesize, that the proposed combined therapies will yield improved clinical effect in this patient population.~The hypotheses in this study is, that the CD-40 agonist APX005M with or without radiotherapy, and in combination with platinum-doublet chemotherapy, will provide the necessary immune activation and serve as a basis for increased clinical effect of the combination.
The overall objective is to demonstrate preliminary efficacy of APX005M-carboplatin-PLD and APX005M-radiotherapy-carboplatin-PLD combinations as treatment for relapsed BRCAwt ovarian cancer patients, where platinum combination therapy is an option.