Journal of Clinical Oncology, Vol 16, 2181-2187, Copyright © 1998 by American Society of Clinical Oncology
Phase I and pharmacokinetic study of KRN8602 alone and with filgrastim in patients with advanced cancer
K Clarke, RL Basser, D Maher, DJ Morgan, J Cebon, RM Fox, JS Hill, C Alt, J Bartlett, H Geldard, AH Kaye and MD Green
Centre for Developmental Cancer Therapeutics, Parkville, Victoria, Australia.
PURPOSE: To determine the recommended dose, toxicity profile, and
pharmacokinetics of KRN8602 (MX2-hydrochloride), a novel morpholino
anthracycline with potent cytotoxicity against anthracycline-sensitive and
resistant experimental tumors in vitro and in vivo. PATIENTS AND METHODS:
KRN8602 was administered alone in increasing doses to patients with
advanced cancer or high-grade gliomas until dose-limiting toxicity (DLT)
was observed in three or more of five patients treated in a dose level.
Because neutropenia was dose limiting, further escalation was investigated
with filgrastim support. RESULTS: Fifty-six assessable patients completed
at least one cycle of chemotherapy. The recommended dose of KRN8602 alone
was 40 mg/m2. Dose escalation was limited by neutropenia. The recommended
dose of KRN8602 with filgrastim was 70 mg/m2, and limiting toxicities were
neutropenia, diarrhea, and vomiting. The most commonly experienced
nonhematologic toxicity was nausea and vomiting. Alopecia and mucositis
were infrequent and mild. Pharmacokinetic parameters showed substantial
variation, although the area under the plasma concentration-time curve
(AUC) and maximum concentration both increased with dose. There was no
relationship between pharmacokinetic parameters and toxicity. CONCLUSION:
KRN8602 at doses of 40 mg/m2 when administered alone and 70 mg/m2 when
administered with filgrastim appeared to be manageable. The major DLTs were
neutropenia and, at higher doses, diarrhea and vomiting. The efficacy of
this drug is currently being tested in phase II studies.