Phase I Clinical Trial of a Day-1, -3, -5 Every 3 WeeksPhase I Clinical Trial of Day-1, -3, -5 Every 3 Weeks Schedule with Titanocene Dichloride (MKT 5) in Patients with Advanced Cancer. (Phase I Study Group of the AIO of the German Cancer Society).

BACKGROUND: Titanocene dichloride (TD) is an organometallic compound with antiproliferative properties in vitro and promising antitumor activity in preclinical in vivo models. The drug interferes with DNA, blocks the S/G(2) phase of the cell cycle and shows antiangiogenic properties. The purpose of this study was to determine the maximum tolerated dose (MTD) and the dose-limiting toxicity (DLT) of a 'split' dose administration schedule (days 1, 3, 5 q 3 weeks). PATIENTS AND
METHOD: Patients with progressive advanced cancer and a creatinine clearance > 60 ml/min qualified for a treatment with TD after standard therapies (radio-, chemo-, hormone therapy) failed. A total of 10 patients (4 females, 6 males) with a median age of 58 (range 49-68) years were treated with 80 mg/m(2) TD at days 1, 3 and 5 (repeated at day 22). The drug was administered as light-protected infusion within 1 h.
RESULTS: Significant side effects were as follows: nausea/vomiting, appetite loss, renal toxicity (elevation of serum creatinine and proteinuria) and liver toxicity (bilirubin and alkaline phosphatase elevation), but no myelosuppression. At the starting dose (3 x 80 = 240 mg/m(2) TD), renal (3 patients) or liver toxicity (1 patient) of grade 3 was judged as DLT. No further dose escalation was possible. No objective tumor remission was observed.
CONCLUSION: The tolerability of TD cannot be improved by splitting the total dose in to three treatments every other day. Compared to previous phase I data using a 3-weekly and a 1-weekly schedule, the 'split' dose administration allowed no further increase of the total drug dose per treatment cycle. Thus, dose intensification by alterations of the application mode does not seem to be possible. Copyright 2000 S. Karger GmbH, Freiburg