Pilot study of celecoxib and infusional 5-fluorouracil as second-line treatment for advanced pancreatic carcinoma.

Background: Cyclooxygenase-2 (COX-2) is up-regulated frequently and may constitute a promising therapeutic target in patients with pancreatic ductal adenocarcinoma (PDAC).

Methods: Patients with advanced PDAC who had progressive disease after gemcitabine-based chemotherapy were eligible for this pilot study. Treatment was comprised of oral celecoxib (400 mg twice daily) and protracted intravenous (i.v.) infusion 5-fluorouracil (5-FU) (200 mg/m(2) per day), both given continuously for a maximum of 9 treatment months, in the absence of disease progression or unacceptable toxicity. Patients were examined weekly for toxicity and were restaged every 6-8 weeks for tumor assessment.

Results: Seventeen patients entered the study. Asymptomatic transaminase elevation was the most common toxicity and reached NCI-CTC (version 3.0) Grade 3-4 in 4 of 133 treatment weeks. No other hematologic or nonhematologic toxicity > Grade 2 was observed. Four patients discontinued celecoxib due to upper gastrointestinal tract toxicity. Two confirmed partial responses (durations of 23 weeks and 68 weeks, respectively) and 2 patients with stable disease (durations of 10 weeks and 13 weeks, respectively) were observed for an overall response rate of 12% (95% confidence interval, 0-27%) in the intent-to-treat population. A significant decrease (> or = 50%) in serum CA 19.9 levels was observed in 3 of 9 evaluable patients. The median time to disease progression was 8 weeks, and the median overall survival was 15 weeks.

Conclusions: The combination of oral celecoxib and 5-FU by protracted i.v. infusion was found to be feasible and well tolerated, and was capable of inducing durable objective responses, even in patients with far advanced, gemcitabine-resistant/refractory PDAC. Further exploration of COX-2 inhibitor/fluropyrimidine combinations is warranted.