OUTLINE: This was a multicenter study. Stage I: Patients received VX-710 IV over 72 hours, followed by doxorubicin IV and vincristine IV four hours after initial VX-710. Vincristine was administered at half dose in the first 3-6 patients. If no more than 1 of 6 patients experienced a dose limiting toxicity in the half dose cohort, 3 additional patients received full dose vincristine. The maximum tolerated dose was defined as the dose preceding that at which 2 of 6 patients experienced a dose limiting toxicity. Stage II: Patients received VX-710 IV over 72 hours, followed by doxorubicin IV and full dose vincristine IV four hours after initial VX-710. Treatment continued for up to 6 courses every 3 weeks in the absence of disease progression or unacceptable toxicity. Patients were followed every 3 months for up to 1 year.