The addition of cisplatin to Abraxane® (nab-paclitaxel) and Gemzar® (gemcitabine) improved survival in patients with pancreatic cancer, according to a study published in JAMA Oncology.
The small, single-arm, open-label, phase Ib/II study included 25 patients (median age, 65 years) with previously untreated metastatic pancreatic ductal adenocarcinoma who were enrolled between December 2013 and July 2016 from three U.S. sites.
Patients received nab-paclitaxel 125 mg/m2 plus gemcitabine 1,000 mg/m2 and cisplatin at various doses of 25 mg/m2, 37.5 mg/m2, and 50 mg/m2 on days one and eight of a 21-day cycle.
The maximum tolerated dose of cisplatin was 25 mg/m2. The most common grade ≥3 treatment-related adverse events were thrombocytopenia (n=17; 68%), anemia (n=8; 32%), and neutropenia (n=6; 24%). Three patients (12%) died, two of which were related to study participation.
Patients completed a median of eight treatment cycles (range, 1-15 cycles).
Improved response, survival with cisplatin
The Response Evaluation Criteria in Solid Tumors responses (primary endpoint) among 24 evaluable patients included two complete responses (8%; this was below the primary endpoint of 25%), 15 partial responses (62%), four stable disease (17%), and three progressive disease (12%).
The median overall survival (OS) was 16.4 months (range, 36-59 months; 95% CI, 10.2-25.3). Sixteen patients (64%) were alive at one year, 10 (40%) at two years, four (16%) at three years, and one (4%) at four or more years.
Median progression-free survival was 10.1 months (95% CI, 6.0-12.5). The overall response rate was 71%, and the disease control rate was 88%.
Historically, nab-paclitaxel plus gemcitabine alone extend OS to 8.5 months in this patient population, so the findings of this study indicate a doubling of median OS with the addition of cisplatin.
“Adding cisplatin to nab-paclitaxel and gemcitabine in this pilot study was associated with substantially increased clinical activity; thus, further investigation of this triple-drug combination in larger studies is warranted,” the authors concluded.