Background: Preclinical data suggested that alpha-interferon (IFN) may potentiate chemotherapy cytotoxicity.
Methods: A prospective multicentric randomized trial was initiated to assess the clinical benefit of adding recombinant alpha-2-IFN to combination chemotherapy in patients with metastatic non-small cell lung cancer. A total of 182 patients were randomized to receive either cisplatin-epidoxorubicin-cyclophosphamide (CEP) combination chemotherapy (cisplatin, 60 mg/m2; epidoxorubicin, 50 mg/m2; and cyclophosphamide, 400 mg/m2 intravenously) alone on day 1 or the same chemotherapy plus recombinant alpha-2-IFN at the dose of 5 MU intramuscularly from day -2 to +4, then 3 times weekly.
Results: The median survival was 6 months in the CEP plus IFN arm versus 5.5 months in the control arm. The log-rank test showed a marginal statistically significant difference (P = 0.045) in favor of CEP chemotherapy, which disappeared when survival curves were adjusted for prognostic factors. Progression-free survival was similar in the two treatment arms. Considering all eligible patients, the response rate was 7.6% in the CEP arm versus 18.9% in the CEP plus IFN arm (P = 0.042). Nearly 40% of the patients receiving IFN had grade 3-4 nadir leukopenia versus 15% in the control arm (P = 0.01) and 12.5% versus 4.2% had grade 3-4 thrombocytopenia. Apart from the usual constitutional symptoms, IFN was also responsible for increased emesis and mucositis.
Conclusions: This study indicates that the addition of recombinant alpha-IFN to CEP chemotherapy can increase response rate and toxicity to treatment without a positive effect on progression-free survival and survival.