A dose escalation study of weekly docetaxel in patients with advanced solid tumors

Purpose: To determine the maximum tolerated dose (MTD) and the dose-limiting toxicity (DLT) of weekly administration of docetaxel for three consecutive weeks every 4 weeks in patients with advanced solid tumors. Patients and methods: A total of 26 patients with malignant tumors refractory to conventional treatment were enrolled in this phase I study; their median age was 62 years. Of the 26 patients, 16 (62%) had previously received more than one chemotherapy regimen and 17 (65%) had previously received taxanes in a 3-week schedule. Docetaxel was administered after appropriate premedication at escalating doses (starting dose 30 mg/m2) as a 1-h i.v. infusion for three consecutive weeks in cycles of 4 weeks. Results: A total of 68 chemotherapy cycles were administered with a median of three cycles per patient (range one to six). The DLT was reached at 45 mg/m2 per week and the dose-limiting events were grade 4 neutropenia, febrile neutropenia, and treatment delay due to incomplete hematologic recovery. The MTD was defined at a dose of 42 mg/m2/week. Grade 3/4 neutropenia occurred in seven patients (27%) (10% of cycles), and four patients (15%) developed febrile neutropenia. There were no deaths due to sepsis. Grade 2 peripheral neurotoxicity was observed in two patients (8%), grade 2 and 3 fatigue in 14 (54%), grade 2 edema in seven (27%), mild allergic reactions in two (8%) and lacrimation in three (12%). One (4%) complete response and eight (35%) partial responses (overall response rate 39%) were observed in 23 evaluable patients. Stable disease and progressive disease were observed in six patients (26%) and eight patients (35%), respectively. All responses were observed in patients with metastatic breast cancer, one of whom had progressed on paclitaxel-based and two of whom had progressed on docetaxel-based chemotherapy. Conclusions: The weekly administration of docetaxel for three consecutive weeks every 28 days is a feasible schedule with a favorable toxicity profile, and can be given on an outpatient basis. Moreover, this schedule of docetaxel administration seems to have an enhanced efficacy, especially in patients with advanced breast cancer who have failed front-line taxane-based chemotherapy.