A pilot study of gamma-1b-interferon in combination with fluorouracil, leucovorin, and alpha-2a-interferon

• Published in: Clinical cancer research 1997-07, Vol.3 (7), p.1125
• Main Authors: Grem, J L, McAtee, N, Murphy, R F, Balis, F M, Cullen, E, Chen, A P, Hamilton, J M, Steinberg, S M, Quinn, M, Sorensen, J M, Arbuck, S G, Lawrence, D, Pang, J, Allegra, C J
• Format: Article
• Language: English
• Subjects: Adult; Aged; Antineoplastic Agents - adverse effects; Antineoplastic Agents - pharmacokinetics; Antineoplastic Agents - therapeutic use; Clinical Protocols; Combined Modality Therapy; Drug Administration Schedule; Female; Fluorouracil - adverse effects; Fluorouracil - pharmacokinetics; Fluorouracil - therapeutic use; Humans; Interferon-alpha - adverse effects; Interferon-alpha - therapeutic use; Interferon-gamma - adverse effects; Interferon-gamma - therapeutic use; Leucovorin - therapeutic use; Male; Metabolic Clearance Rate; Middle Aged; Neoplasms - therapy; Pilot Projects; Recombinant Proteins
• ISSN: 1078-0432; 1557-3265

The combination of IFN-alpha-2a (IFN-alpha) and IFN-gamma-1b (IFN-gamma) has been found to produce more than additive cytotoxicity with fluorouracil (5-FU) in HT 29 colon cancer cells due to enhanced DNA-directed effects. We therefore studied the combination of IFN-gamma with IFN-alpha, 5-FU, and leucovorin (LV) in a clinical trial. Fifty-three patients received an initial cycle of 5 million units (MU)/m2 IFN-alpha s.c. on days 1-7 with 500 mg/m2 LV and 370 mg/m2 5-FU i.v. on days 2-6. IFN-gamma was then added once tolerable doses of 5-FU and IFN-alpha were established for each patient. IFN-gamma was administered at one of six dose levels between 0.3-4.8 MU/m2 s.c. on days 1-7. This design permitted comparison of the clinical toxicity and pharmacokinetics of 5-FU in two consecutive cycles in an individual treated with the same doses of 5-FU/LV/IFN-alpha in the absence and presence of IFN-gamma. In 43 matched patient cycles, the addition of IFN-gamma did not seem to worsen gastrointestinal toxicity, and skin toxicity tended to be milder. 5-FU clearance was higher in 14 cycles with IFN-gamma compared to the patient's prior cycle with the same doses of 5-FU/LV/IFN-alpha: 798 +/- 309 versus 601 +/- 250 ml/min/m2 (mean +/- SD; P = 0.04). In these 28 cycles, the median 5-FU clearance was significantly lower in 11 cycles that were complicated by more severe diarrhea: 524 versus 798 ml/min/m2 (grade 2 versus 0-1; P = 0. 0032). Overall, 38% and 26% of patients had grade 3-4 diarrhea and mucositis. Dose reductions of IFN-gamma for chronic fatigue, malaise, or anorexia were ultimately required more frequently with >/=2.4 MU/m2 (P = 0.018), and the maximum tolerated dose of IFN-gamma was considered to be 1.2 MU/m2/ day. Objective responses were seen in 41% of 29 measurable colorectal cancer patients. Compared to our previous experience with 5-FU/LV/IFN-alpha, IFN-gamma and IFN-alpha appeared to have opposite effects on 5-FU clearance. These results suggest that any potential benefit of adding IFN-alpha to 5-FU/LV on this schedule may not depend solely on alterations in 5-FU clearance.