摘要

Background: The nucleoside 3%26apos;-c-ethynylcytidine (TAS-106) was designed to inhibit RNA synthesis which occurs throughout the cell cycle except for the M phase. TAS-106 is incorporated into cells, is rapidly phosphorylated to a monophosphate form, and is preferentially distributed into malignant cells. Preclinical studies showed that TAS-I06 has a wide antitumor spectrum against human cancer xenografts. This phase 1 study was conducted in order to determine the recommended phase 11 dose ofTAS-106 administered once per week for three consecutive weeks, every 28 days in patients with solid tumors. Patients and Methods: Patients were enrolled in cohorts of three, starting at 0.22 Inglm21dose. Patients received at least two doses in order to be evaluable in each dose cohort. Dose escalation was stopped if two or more patients experienced dose limiting toxicity at any dose level. Results: In 20 evaluable patients, TAS-106 was given at the following dose levels (mg/m2/dose): 0.22 (3 pts), 0.33 (3 pts), 0.66 (3 pts), 0.99 (1 pt), 1.32 (3 pts), 2.64 (3 pts) and 3.96 (I pt). Three additional patients were evaluated at 2.64 mghn21dose for further characterization of toxicity and safety. A total of 16 patients completed courses 1 and 2. All 21 patients enrolled experienced at least one adverse event. The AE attributed to the study drug was grade 2 peripheral neuropathy characterized by peripheral sensory neuropathy, numbness, tremor, pain. and hyperesthesia involving the fingers, hands, toes, and feet. Conclusion: Due to neurotoxicity the MTD was the 2.64 mg/m(2)/dose for the study schedule. No suggested phase 11 dose was determined. However, at the 1.32 mg/m(2)/dose level, no patients experienced DLTs during course 1 or 2. This could he further studied to determine its viability as a potential phase II dosage.

  • 出版日期2012-5