Difluoromethylornithine and leukocyte interferon: A phase I study in cancer patients

M. Talpaz, C. Plager, J. Quesada, R. Benjamin, H. Kantarjian, J. Gutterman

Research output: Contribution to journalArticlepeer-review

23 Scopus citations

Abstract

Difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase, and human leukocyte interferon (IFN-α) have synergistic anti-tumor activities in vivo in B 16 melanoma and in vitro against several human cancer cell lines. We have, therefore, carried out a phase I combination study with DFMO plus alpha interferon in the following manner: DFMO was maintained at a steady dose for the first four levels, 1.5 g/m2 every 6 hr. IFN-α was given in 100% increments ranging from 0.4 × 106U/m2 to 3.2 × 106U/m2 i.m. daily. At the fifth dose level both IFN-α and DFMO were raised by 100 and 50% respectively. From levels one through four the combination was well tolerated with no dose interruptions required because of G.I. toxicity or myelosuppression. However, at dose level 5, one-third of the patients required dose cessation and decrease due to nausea, vomiting and diarrhea. We conclude that for phase II studies the maximal tolerated dose is 3.2 million units of IFN-α/m2 and 1.5 g/m2 of DFMO every 6 hr. Of 12 patients with metastatic melanoma, 2 had partial remissions lasting 58+ and 36+, weeks. Two additional patients had minor responses lasting 29 and 32+, weeks. Minor responses were observed in a patient with colon carcinoma and a patient with renal carcinoma. The clinical activity of the combination is currently being pursued in a phase II study among patients with metastatic malignant melanoma.

Original languageEnglish (US)
Pages (from-to)685-689
Number of pages5
JournalEuropean Journal of Cancer and Clinical Oncology
Volume22
Issue number6
DOIs
StatePublished - Jun 1986

ASJC Scopus subject areas

  • Oncology

Fingerprint

Dive into the research topics of 'Difluoromethylornithine and leukocyte interferon: A phase I study in cancer patients'. Together they form a unique fingerprint.

Cite this