Therapeutic effects of single-push or fractionated injections or continuous infusion of oxazaphosphorines (cyclophosphamide, ifosfamide, Asta Z 7557).

This report describes some experimental and clinical studies showing the following: (1) in animals under protection of mesna the dose of ifosfamide (Ifo) can be increased significantly; (2) fractionated administration of Ifo, cyclophosphamide (CPA), or the stabilized metabolite of cyclophosphamide (ASTA Z 7557) is less toxic than single push-injection of the same total daily dose and therapeutically more effective; and (3) in humans under the protection of mesna the continuous infusions of ifosfamide over 5 days leads to an increase of the MTD compared with single daily short-term infusion and responses in some solid tumors, e.g., soft tissue sarcomas.