Phase I/II trial of autophagy inhibition in combination with neoadjuvant gemcitabine in patients with high-risk pancreatic adenocarcinoma: Safety, clinical response, and correlative studies.

Abstract

218 Background: Autophagy is a cell survival mechanism, upregulated in pancreatic ductal adenocarcinoma, correlating adversely with response to therapy and prognosis. The autophagy inhibitor hydroxychloroquine (HCQ) is a novel treatment. Methods: A Phase I/II trial examined pre-operative gemcitabine with HCQ in the treatment of pancreatic cancer patients. Eligibility was restricted to those predicted to have limited survival following surgical resection. Two doses of gemcitabine (1500mg/m2) were administered with oral HCQ (200-1200mg/day) for 31 days until operation in a Storer phase 1 design. Primary endpoint was the safety and tolerability of HCQ. Secondary endpoints were clinical response as assessed by CA 19-9 and R0 resection rates. LC3 and cleaved caspase 3 staining were assessed as biologic correlates to clinical response. Additional exploratory endpoints included serum levels of HMGB1, IL-6, and DNA DAMPs. Results: Thirty-five patients were enrolled in the safety phase of the trial. Two patients withdrew consent prior to treatment and two others were removed due to a stroke and allergic rash, resulting in 31 patients completing treatment. There were no dose limiting toxicities and no treatment delays. 14 patients (45%) had a decrease in CA19-9 of >50% following treatment. 29 patients (94%) underwent surgical resection with an R0 resection rate of 81%. There was one peri-operative mortality (3.2%) with significant morbidity (Grade 3/4) affecting 29% of patients. Increases in pancreatic LC3 staining were consistent with autophagy inhibition. There was a statistically non significant trend towards increased apoptosis with increasing doses of HCQ. Both mitochondrial and nuclear DNA (p = .09) decreased. During treatment, HMGB1 and IL-6 levels rose and then returned to normal levels. Conclusions: Pre-operative autophagy inhibition with HCQ in combination with gemcitabine is safe and tolerable and associated with biomarkers of response. This regimen has promise as a biologically active strategy and future trials will examine HCQ in combination with Nab-paclitaxol/Gemcitabine combinations. Clinical trial information: NCT01128296.