Pharmacokinetics of high-dose oral calcitriol: results from a phase 1 trial of calcitriol and paclitaxel.

Objectives: The data reported are from a trial designed to determine, in patients with advanced cancer, the maximum tolerated dose and pharmacokinetics of calcitriol when administered with paclitaxel, an agent whose antitumor activity in in vitro and in vivo studies has been shown to be enhanced by calcitriol. An additional goal was to evaluate the relationship between calcitriol dose and hypercalcemia.

Methods: Calcitriol was given orally for 3 consecutive days each week, and paclitaxel (80 mg/m(2)) was given intravenously weekly.