Phase II study of elraglusib (9-ING-41), a GSK-3β inhibitor, in combination with gemcitabine plus nab-paclitaxel in previously untreated metastatic pancreatic cancer

INTRODUCTION: The purpose of this study was to assess the efficacy and safety of elraglusib (9-ING-41), a GSK-3β inhibitor, in combination with gemcitabine/nab-paclitaxel (GnP) in previously untreated metastatic pancreatic ductal adenocarcinoma (mPDAC). MATERIAL AND METHODS: In a nonrandomized, Simon's two-stage, phase II study, patients with mPDAC received elraglusib 15 mg/kg on days 1 and 4 each week and GnP on days 1, 8, and 15 in a 28-day cycle. The primary endpoint was disease control rate (DCR); secondary endpoints were objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and treatment-emergent adverse events (TEAEs). RESULTS: A total of 42 patients, who were enrolled and treated, had a median age of 67 years and were 57.1% male. Overall, 38 patients received elraglusib at 15 mg/kg and 4 at 9.3 mg/kg with GnP. DCR was 35.7% [95% confidence interval (CI) 21.6% to 52.0%], and ORR was 26.2%. The median PFS and OS were 5.4 months (95% CI 4.4-9.2 months) and 11.9 months (95% CI 7.8-16.5 months), respectively. Most common TEAEs were visual impairment (83.3%), fatigue (69%), and nausea (66.7%). Grade ≥3 TEAEs occurred in 85.7% of patients and included neutropenia (52.4%), leukopenia (42.9%), and fatigue (21.4%). The dose of elraglusib was reduced to 9.3 mg/kg due to increased exacerbation of GnP-related toxicities and frequent dose interruptions and reductions of elraglusib. CONCLUSIONS: Elraglusib/GnP showed preliminary clinical activity. In terms of safety, elraglusib resulted in a modest exacerbation of GnP-related toxicities, leading to a dose reduction of elraglusib to 9.3 mg/kg twice a week. Based on the initial efficacy and safety data, the study was amended to a randomized phase II study that will evaluate the 9.3 mg/kg dose.