Phase Ib Trial Of Cabazitaxel And Tasquinimod In Men With Heavily Pretreated Metastatic Castration Resistant Prostate Cancer (Mcrpc): The Catch Trial.

190 Background: Cabazitaxel resistance develops within a few months of treatment initiation in most men with mCRPC in post-docetaxel, and thus combination therapy with other active agents may improve outcomes. Tasquinimod is an oral immunomodulatory agent with anti-angiogenic and anti-tumor in preclinical models of PC and clinical activity in phase II and III trials. Methods: We conducted a phase I dose escalation trial of cabazitaxel plus tasquinimod in men with mCRPC. Cabazitaxel was dosed at 25 mg/m2 every 3 weeks with low dose prednisone and PEG-filgrastim support, and tasquinimod dose levels included 0.25, 0.5, and 1.0 mg, using a 3 week within-patient dose escalation for dose levels 2 and 3, starting all patients at 0.25 mg once daily. The primary objective was to define the recommended phase II dose (RP2D) based on safety and dose limiting toxicity. Preliminary efficacy (PSA decline, PFS) and pharmacokinetic interactions were key secondary objectives. Results: We enrolled 25 men with mCRPC who had ...