KW-2149-induced pulmonary toxicity is not prevented by corticosteroids: a phase I and pharmacokinetic study

KW-2149 is a new, semisynthetic, C7-N-Substituted, mitomycin C analog showi ng antitumor activity both in vitro and in vivo, equal or superior to mitom ycin C, In a phase I study, KW-2149 was administered as an i.v, bolus injec tion every 21 days and at a dose of 100 mg/m(2) pulmonary toxicity was dose limiting. Animal studies have indicated since that KW-2149-induced pulmona ry toxicity can be prevented by pretreatment with corticosteroids. This pap er presents the results of a further phase I study of KW-2149 with corticos teroid pretreatment. Patients were treated with oral dexamethasone 8 mg eve ry 12 h, starting 24 h before KW-2149 administration, for 5 days. KW-2149 w as given as an i.v. bolus injection every 21 days. Seventeen patients were treated with a total of 48 courses. Six patients received 60 mg/m(2) and 11 patients 75 mg/m(2). Two courses were not evaluable for toxicity. Signific ant lung toxicity was observed in at least three patients treated with a do se of 75 mg/m(2) KW-2149 and pulmonary toxicity was therefore considered th e dose-limiting toxicity at 75 mg/m(2), No other important side effects wer e noted. One partial response was observed in a patient with colorectal can cer, Pretreatment with dexamethasone failed to suppress KW-2149-induced lun g toxicity. [(C) 1999 Lippincott Williams & Wilkins.].