Objectives

Combinations of gemcitabine, 5-fluorouracil (5-FU), and platinum have demonstrated improved outcomes compared with singlet chemotherapy in pancreatic and biliary cancers. This phase II study examined efficacy and safety of a novel schedule of cisplatin, fixed-dose-rate gemcitabine and infusional 5-FU.

Materials and methods

Patients with metastatic adenocarcinoma of the pancreas or biliary tract, previously untreated or having received 1 cytotoxic regimen for advanced disease, were treated with gemcitabine 1000 mg/m intravenously (IV) over 100 minutes, cisplatin 35 mg/m IV over 30 minutes, and 5-FU 2400 mg/m IV over 48 hours on day 1 of a 14-day cycle. Patients were treated until disease progression or for 12 cycles. After 12 cycles, patients with stable or responding disease could continue gemcitabine and 5-FU. The primary endpoint was objective response.

Results

Thirty-nine patients were treated: 8 with biliary cancer (all untreated) and 31 with pancreatic cancer (17 untreated, 14 previously treated). Best response in 25 untreated patients was partial response in 40%, stable disease in 40%, and progressive disease in 20%. In 14 previously treated pancreatic patients, best response was partial response in 7%, stable disease in 50%, and progressive disease in 43%. Median overall survival in untreated patients was 10.3 versus 4.9 months in previously treated patients. Adverse events were primarily uncomplicated hematologic toxicity, ≥grade 3 neutropenia (54%), anemia (21%), and thrombocytopenia (13%).

Conclusion

Biweekly cisplatin, fixed-dose-rate gemcitabine, and infusional 5-FU demonstrated a high response rate and were well tolerated, encouraging further investigation of this regimen in metastatic pancreatic and biliary cancers.

Background Cabozantinib and gemcitabine improve tumor control in pancreatic ductal adenocarcinoma (PDAC) in preclinical models through c-Met inhibition. We sought to determine the maximum tolerated dose (MTD) of this combination in patients with advanced PDAC. Methods Patients with ≤1 prior treatment and adequate performance status were eligible. Cabozantinib was given orally once daily, beginning day (-)7 and continued with gemcitabine given intravenously on days 1, 8, and 15 every 28 days. Dose level was assigned using Time to Event Continual Reassessment Method (TITE-CRM). Primary endpoint was MTD, defined as the highest dose level at which ≤25 % of patients incurred a dose-limiting toxicity (DLT). Secondary endpoints included response rate, progression-free survival (PFS), overall survival (OS) and urinary biomarker assessment. Results Twelve patients were enrolled and treated with 10 patients evaluable for DLT. The probability of DLT was >25 % for all dose levels tested, and thus an MTD was not determined. DLTs included grade 3 ALT/AST elevations and thrombocytopenia. Three patients had partial responses, but each discontinued therapy due to toxicity. Median PFS and OS were 4.7 (95 % CI: 1.4-9.7) and 10.1 months (95 % CI: 3.6-20.6). Exploratory biomarker analysis showed correlation of c-Met and VEGF levels with response. Conclusions An MTD for the combination was not established. Cabozantinib and gemcitabine appear impractical for further development due to DLT at low doses and continuing toxicities with ongoing therapy. Acknowledging the small sample size, responses were seen suggesting further investigation of c-Met inhibition in PDAC may be warranted.