3-deazauridine and Thrombocytopenia

The uridine analog 3-deazauridine has been given to 19 patients in a phase I and pharmacokinetic study. Only mild toxicity was seen at doses less than 1200 mg/m2/day for 5 days. At a dose of 1200 mg/m2/day x 5, leukopenia (mean wbc count nadir of 2650/mm3) was seen in nine of 12 patients and thrombocytopenia (mean platelet count nadir of 47,000/mm3) in five of 12 patients. Nausea and vomiting and oral toxicity were each seen in two patients, and diarrhea and skin toxicity occurred in one patient each. Pharmacokinetic studies indicate a biphasic plasma decay with a beta-half-life of 6.9 hours and urinary excretion, mostly of unchanged drug, as the most important route for drug elimination. A dose of 1200 mg/m2/day x 5 is recommended for phase II studies and great caution is advised in administering the drug in the presence of renal impairment.

Topics: 3-Deazauridine; Adult; Aged; Child, Preschool; Drug Evaluation; Female; Humans; Kinetics; Leukopenia; Male; Middle Aged; Thrombocytopenia; Uridine

A phase I trial of the uridine analog 3-deazauridine was undertaken in 44 adults with solid tumors. The drug was given as a 5-day continuous infusion repeated every 3-4 weeks. The dose-limiting toxic effect was granulocytopenia. Patients with prior nitrosourea therapy or extensive irradiation also had significant thrombocytopenia, and the lowest dose tested, 800 mg/m2/day, was excessive for this group. Mucositis was occasionally severe and was particularly marked in previously irradiated areas. Nausea was mild to moderate. There were isolated episodes of rash, headache, chest pain, and blurred vision. For patients without extensive prior therapy, the recommended dose is 1000 mg/m2/day. No complete or partial remissions were noted.

Topics: 3-Deazauridine; Adult; Aged; Agranulocytosis; Drug Administration Schedule; Drug Evaluation; Female; Humans; Infusions, Parenteral; Leukocyte Count; Male; Middle Aged; Nausea; Neoplasms; Platelet Count; Thrombocytopenia; Uridine