A phase Ib/II pilot trial with nab-paclitaxel plus gemcitabine plus cisplatin in patients (pts) with stage IV pancreatic cancer.

Abstract

341 Background: Genomes of metastatic pancreatic cancers frequently contain intrachromosomal aberrations indicating DNA repair abnormalities associated with sensitivity to DNA damaging agents such as the platinums. Cisplatin was added to a nab-paclitaxel + gemcitabine regimen, which has been determined to improve survival over gemcitabine alone (NEJM 2013; 369:1691-1703). The objectives are to determine the efficacy and safety of nab-paclitaxel and gemcitabine plus cisplatin in patients with Stage IV pancreatic cancer. Methods: Eligibility criteria included Stage IV adenocarcinoma of the pancreas, no prior chemotherapy for systemic disease, KPS ≥ 70; life expectancy ≥ 12 weeks and measurable disease. Doses are nab-paclitaxel 125 mg/m2 undiluted, gemcitabine 1000 mg/m2 in 500 ml of normal saline (NS), each infused over 30 minutes on days 1 and 8 of a 21 day cycle, along with 3 different dose levels of cisplatin (25, 37.5 or 50 mg/m2) in 500 ml of NS infused over 60 minutes, after the nab-paclitaxel infusion. Pre and post cisplatin hydration was given. The maximum tolerated dose and phase II dose of cisplatin is 25 mg/m2. Results: 25 pts were treated; 24 were evaluable (baseline and ≥ 1 follow up CT scan). The most common drug related grade (gr) 3 - 4 adverse events (AEs), n = 25, were thrombocytopenia 76% (gr 3 = 36%, gr 4 = 40%) with no serious bleeding events, anemia 32% (gr 3 = 32%, gr 4 = 0%), neutropenia 24% (gr 3 = 20%, gr 4 = 4%), infection 20% (gr 3 = 16%, gr 4 = 4%), and diarrhea 16% (gr 3 = 16%, gr 4 = 0%). Peripheral neuropathy ≥ gr 3 was seen in only 1 pt (gr 3 = 4%). Grade 5 AEs were infection (1), cardiac arrest (1), and stroke (1). Median time on therapy was 5.5 months, range (1 – 9.5). By RECIST 1.1 criteria, 2 pts had complete response (8.3%), 15 partial response (62.5%), 4 stable disease (16.7%), and 3 progressive disease (12.5%). Median overall survival to date as of 11/10/16 is 16.5 months. Conclusions: Although a small study, the high response rate and landmark evolving median survival are very encouraging. This regimen is being expanded in patients with stage IV pancreatic cancer, neoadjuvant and adjuvant settings. Clinical trial information: NCT01893801.