Phase 1 study of Paclitaxel administered twice weekly to children with refractory solid tumors: a pediatric oncology group study.
OBJECTIVE
To perform a phase 1 trial to determine the maximum tolerated dose and the dose-limiting toxicities of paclitaxel in children with refractory or recurrent solid tumors. Paclitaxel was administered twice weekly, increasing from four to six doses every 21 to 28 days.


METHODS
Paclitaxel was administered as a 3-hour intravenous infusion twice weekly. The initial dose was fixed at 50 mg/m2/dose twice weekly for 2 weeks (four doses), every 21 days. The number of twice-weekly doses per course was increased to six in the next cohort. In subsequent cohorts, the number of twice-weekly doses per course was fixed at six, every 28 days, and dosage was increased in 25% increments.


RESULTS
Sixteen assessable patients were enrolled at three levels. Neutropenia was the dose-limiting toxicity at 65 mg/m2/dose, twice weekly x 6 doses, every 28 days. Nonhematologic toxicities were minor. No antitumor responses were observed.


CONCLUSIONS
Protracted twice-weekly dosing of paclitaxel is limited by neutropenia. The maximum tolerated dose of paclitaxel administered twice weekly x 6 doses, every 28 days, was 50 mg/m2/dose.
Hayashi
Robert J
RJ
University School of Medicine, Division of Pediatric Hematology/Oncology, Box 8116, 660 South Euclid, St. Louis, MO 63110, USA. hayashi_r@kids.wustl.edu
Blaney
Susan
S
Sullivan
Jim
J
Weitman
Steve
S
Vietti
Teresa
T
Bernstein
Mark L
ML
D000740:Anemia / Q000139:chemically induced; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D002648:Child; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D009369:Neoplasms / Q000097:blood / Q000188:drug therapy*; D009503:Neutropenia / Q000139:chemically induced; D017239:Paclitaxel / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D018579:Patient Selection; D010976:Platelet Count
D000972:Antineoplastic Agents, Phytogenic; D017239:Paclitaxel