Phase II study of calcitriol-enhanced docetaxel in patients with previously untreated metastatic or locally advanced pancreatic cancer

Purpose: To determine the safety and efficacy of weekly high-dose oral calcitriol and docetaxel, given to patients with non-resectable, incurable pancreatic cancer. Patients and Methods: Twenty-five patients were enrolled onto this phase II study. Patients were treated with oral calcitriol 0.5 μg/kg on day 1, followed by docetaxel 36 mg/m² IV on day 2, administered weekly for three consecutive weeks, followed by 1 week without treatment. Patients followed a low-calcium diet and increased their hydration. The primary end-point of the trial was time-to-progression. Results: Three of 25 patients attained a partial response (12%, 95% CI 3 to 31) and seven (28%) achieved stable disease. Median time-to-progression was 15 weeks, and median overall survival was 24 weeks. Toxicities observed (hyperglycemia, fatigue) were mostly attributable to the docetaxel or its pre-treatment. Conclusions: This regimen of high-dose calcitriol with docetaxel may have activity in incurable pancreatic cancer, with a modest increase in TTP when compared to historical findings using single-agent docetaxel. However, results do not appear superior to those seen with gemcitabine, with or without erlotinib.