A phase I and pharmacokinetic study of capecitabine in combination with radiotherapy in patients with localised inoperable pancreatic cancer

Abstract

Purpose: The purpose of this phase I study was to determine the safety, toxicity, maximum tolerated dose, and pharmacokinetics of capecitabine when administered concurrently with radiotherapy in patients with localised, inoperable pancreatic adenocarcinoma.

Methods: Eligible patients, with adequate performance status and organ function, were treated in escalating dose cohorts with capecitabine, administered 7 days a week, twice daily, and radiotherapy (50.4 Gy in 28 fractions over 38 days). Cohorts of six patients were treated at four planned dose levels. Pharmacokinetic (PK) studies were undertaken on day 1 of treatment.

Results: Twenty-five patients, performance status ECOG ≤2, were recruited to the study. Dose-limiting toxicities were grade 3 vomiting (1 patient) and grade 3 fatigue (1 patient), both at 1,000 mg/m². The recommended phase II dose was 825 mg/m². No grade 3/4 haematological toxicities were observed. PK studies did not suggest any effect of pancreatic malignancy or concurrent radiotherapy on the PK parameters of capecitabine and its metabolites.

Conclusion: Capecitabine-based chemo-radiotherapy, using a twice daily dosing schedule of 825 mg/m² given 7 days per week concurrently with 50.4 Gy external beam radiotherapy, is well tolerated in patients with locally advanced pancreatic cancer.