bms184476 and Neutropenia

This review describes the experimental and clinical properties of new taxanes and epothilones. Six new taxanes are currently in clinical trials: BMS 184476, BMS 188797, BMS 275183, IDN 5109/BAY 598862, RPR 109881A et RPR 116258 All these derivatives share the same feature which is a decreased recognition by Pgp-170, the product of the MDR1 gene. This confers innovative properties such as in vitro and in vivo activities on tumors expressing the Pgp-170, activity by the oral route. Identification of other families of molecules bearing the same mechanism of action as taxol has been a goal pursued by many groups. The discovery of epothilones led to the pharmaceutical development of two molecules: EPO 906 (which corresponds to the natural compound epothilone B) and BMS 247550. Phase I clinical trials have established that all these investigational drugs (taxanes and epothilones) can be safely administered in patients, the limiting toxicity being most of the time febrile neutropenia. Many tumor responses have been noted.

Topics: Animals; Antineoplastic Agents, Phytogenic; Bridged-Ring Compounds; Clinical Trials, Phase I as Topic; Drug Screening Assays, Antitumor; Humans; Mice; Neutropenia; Paclitaxel; Taxoids

The study was designed to establish the maximum administered dose and maximum tolerated dose (MTD) of BMS-184476, an analogue of paclitaxel, given weekly for 3 consecutive weeks every 28 days, later amended to a regimen of weekly administration for 2 consecutive weeks every 21 days.. Adult patients with solid tumors received BMS-184476 i.v. on days 1, 8, and 15 without premedication. The trial followed a modified accelerated titration design. Doses of 7, 14, 28, 40, 50, and 60 mg/m(2)/wk were investigated. Pharmacokinetics of BMS-184476 in plasma and urine were investigated by high-performance liquid chromatography assay.. Fifty-three patients were treated; the maximum administered dose was 60 mg/m(2)/wk, and the MTD was 50 mg/m(2)/wk. Dose-limiting neutropenia was the main toxicity. Neutropenia at the higher dose levels frequently prevented administration of the day 15 dose, and a modified schedule at MTD dosing on days 1 and 8 every 21 days was evaluated and found more feasible for Phase II studies. Diarrhea was the main nonhematological toxicity; other toxicities were vomiting, cumulative fatigue, and loss of appetite. Two patients died of neutropenia-related complications. Antitumor activity was observed in patients with breast and non-small cell lung cancer, with confirmed partial responses in 22% of patients. BMS-184476 was the main species found in the plasma with <5% present as paclitaxel or sulfoxide metabolites. The PKs of BMS-184476 appeared to be linear in the dose range of 7-60 mg/m(2).. The recommended dose and schedule of weekly BMS-184476 is 50 mg/m(2) on days 1 and 8 every 21 days.

Topics: Adult; Aged; Antineoplastic Agents, Phytogenic; Diarrhea; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Humans; Male; Middle Aged; Molecular Structure; Neoplasms; Neutropenia; Paclitaxel; Remission Induction; Taxoids