Phase I study of docetaxel administered by bi-weekly infusion to patients with metastatic breast cancer

Background. To find a more convenient and tolerable schedule than the tri-w eekly or weekly schedules, we conducted a dose escalation study Of bi-weekl y docetaxel. Materials and Methods. Between March 1998 and June 1999, 16 pa tients entered this phase I study. The starting dose was 40 mg/m(2), with p lanned dose escalation to 45, 50 and 55 mglm, in consearrive patient cohort s. Patients continued to receive the assigned treatment at the same dose le vel bi-weekly, provided that they did not develop progressive disease, refu se further treatment. or experience unacceptable toxicity. Results. Grade 4 neutropenia lasting for more 4 days was seen at nose level 3 in all three patients. Only one patient who had previously received intensive chemothera py required granulocyte colony stimulating factor (G-CSF) to prevent neutro penic fever and there were no actual episodes of neutropenic fever Grade 3 asthenia and Grade 3 elevation of serum glutamic oxaloacetic transaminase w ere noted in only one patient treated at a nose of 40 mg/m(2). Grade 3 skin toxicity and grade 2 elevation of serum glutamic oxaloacetic transaminase were seen in only one patient treated at a dose of 55 mg/m. Cumulative toxi city was not severe in all patients. Although grade 3 and/or grade 4 neutro penia were noted in eight patients (50%), all except one who received treat ment at dose of 55 mg/m(2) did not need G-CSF. Nail toxicity and peripheral edema seemed to be related to the number of treatment cycles. Severe fatig ue and asthenia were never seen in all patients. Conclusion. 1) The maximum -tolerated nose of docetaxel when administered by this bi-weekly schedule w as 55 mg/m(2); 2) Docetaxel administered on a bi-weekly basis well tolerate d.