708P - A phase I/Ib, multi-center trial of ARQ-761 (Beta-Lapachone) with gemcitabine/nab-paclitaxel in patients with advanced pancreatic cancer

Abstract

BackgroundARQ761 (β-lapachone) is a hydroquinone analog that exploits the unique elevation of NQO1 found in 90% of pancreatic cancer cells and causes tumor-specific cell death by eliciting a futile redox cycle generating high levels of reactive oxygen species and ultimately PARP1 hyperactivation-dependent cell death. ARQ761 induces cell death which is: (i) not dependent on p53 status; (ii) not dependent on cell cycle status; (iii) not affected by known oncogenic driver or carrier mutations; and (iv) not affected by loss of caspases. We demonstrated that ARQ761 has synergistic antitumor activity with chemotherapy in pancreatic cancer preclinical models. MethodsThis was a single arm phase-1b clinical trial of ARQ-761 plus gemcitabine and nab-paclitaxel for patients with pancreatic cancer. The primary objective was to determine the maximum tolerated dose of ARQ 761 in combination with chemotherapy. Secondary objectives were to assess clinical activity, safety, tolerability and pharmacodynamic effects. Patients with metastatic pancreatic adenocarcinoma not treated with prior gemcitabine with adequate hematologic, renal and liver function and good performance status were enrolled. Dose levels are described in the table. Immunohistochemistry was used to assess for NQO1 expression. ResultsFifteen patients were evaluable for safety, 67% were male, 53% had received prior chemotherapy and 96% tested positive for NQO1 expression. The most common treatment related toxicities were anemia and fatigue. The following dose limiting toxicities were observed (dose level 1: neutropenia, anemia, dose level -1 fatigue). The maximum tolerated dose of ARQ761/gemcitabine/nab-paclitaxel is 156/800/100mg/m2. Tumour response was stable disease in 53% Pharmacodynamic analysis was performed on post treatment biopsies. ConclusionsWe report results of a phase 1b clinical trial of the novel NQO1 bioactivatable compound, ARQ761, in combination with gemcitabine/nab-paclitaxel. Treatment related toxicities were observed which were noted in preclinical models and managed with routine dose adjustment. Clinical trial identificationNCT02514031. Legal entity responsible for the studyUT Southwestern Medical Center. FundingPancreatic Cancer Action Network, Rising Tide, Gateway, Arqule Pharmaceuticals. DisclosureM.S. Beg: Research grant / Funding (institution): Arqule; Advisory / Consultancy: Array; Advisory / Consultancy, Speaker Bureau / Expert testimony: BMS; Advisory / Consultancy, Speaker Bureau / Expert testimony: Ipsen; Advisory / Consultancy: Boston Biomedical; Advisory / Consultancy: Guardant; Advisory / Consultancy: Genentech. D. Boothman: Research grant / Funding (institution): Arqule; Advisory / Consultancy: Toray global; Speaker Bureau / Expert testimony: systems oncology. Y. Arriaga: Full / Part-time employment: IBM. A. Sanjeeviaiah: Advisory / Consultancy, 1500$: Guardant health. B. Schwartz: Full / Part-time employment: Arqule. All other authors have declared no conflicts of interest.