Journal of Clinical Oncology, Vol 15, 1974-1984, Copyright © 1997 by American Society of Clinical Oncology
Phase I and pharmacologic study of penclomedine, a novel alkylating agent, in patients with solid tumors
S O'Reilly, LB Grochow, RC Donehower, TL Chen, K Bowling, NR Hartman, RF Struck and EK Rowinsky
Johns Hopkins Oncology Center, Baltimore, USA.
PURPOSE: To determine the maximum-tolerated dose (MTD), principal
toxicities, and pharmacologic behavior of penclomedine, a novel alkylating
agent. PATIENTS AND METHODS: Penclomedine (45 to 550 mg/ m2/d every 3
weeks) was administered as a 1- or 3-hour intravenous (IV) infusion for 5
consecutive days to patients with solid tumors. RESULTS: On a 1-hour dosing
schedule, ataxia, vertigo, nystagmus, and a motor aphasia were the
principal toxicities of penclomedine. These neurologic effects were
dose-related, and evolved from complaints of somnolence and dizziness, to
more pronounced signs and symptoms of cerebellar dysfunction. Up to and
including doses of 415 mg/m2, these effects were well tolerated and
resolved within 2 hours posttreatment. In contrast, both patients treated
at the 550-mg/m2 dose level experienced a dose- limiting constellation of
perinfusional aphasia and vertigo, with either ataxia of over 2 weeks'
duration or recurrent dizziness. Prolongation of the infusion duration to 3
hours at this dose level resulted in less neurotoxicity; however, delayed
trilineage hematologic toxicity precluded timely administration on this
schedule. A statistically significant relationship was demonstrated between
the development of ataxia and maximum plasma concentrations of
penclomedine. CONCLUSION: Neurotoxicity was the dose-limiting toxicity
(DLT) of penclomedine administered as a 1-hour infusion daily for 5 days
every 3 weeks, and the recommended dose for further evaluations was 415
mg/m2. The nature of the principal toxicities and the lack of any
detectible antitumor activity indicate that phase II evaluations of
penclomedine on this administration schedule should be focused on specific
disease settings, such as breast cancer and intracerebral tumors, in which
antitumor activity has been demonstrated.