Combined Betaseron R (recombinant human interferon beta) and radiation for inoperable non-small cell lung cancer

Based on in vitro evidence of radiosensitization by Betaseron (beta-IFN), a Phase I/II study was undertaken to determine toxicity and response using combined radiation (RT) and B-IFN in patients with unresectable Stage III and nonsmall cell lung cancer.

Varying doses of beta-IFN(10 to 90 x 10(6) IU) were administered IV immediately preceding RT on the first three days of weeks 1, 3, and 5. The RT dose was 1.8 Gy/day, 5 days/week for a total of 54 or 59.4 Gy.

Thirty-nine patients were entered, 32 of whom were evaluable. The median follow-up time at time of analysis was 60 months. Responses were based on CT scan. The response rate for the total group was 81% with 44% achieving complete response. Seventy-eight percent of patients with complete response survived a minimum of 21 months. Twenty-six patients had Stage III A/B disease with a median tumor size of 6.5 cm. and median survival was 19.7 months. The 5-year actuarial survival for this group was 31%, with a plateau persisting after 3 years. There were no treatment related deaths nor any event of life threatening toxicity. Of eight patients surviving 3-5 years, no long-term toxicity has been observed. Karnofsky indices were 90-100 and respiratory symptoms were minimal.

beta-IFN is well-tolerated. Response and survival rates are sufficiently encouraging to warrant further investigation in a randomized trial which has been accepted as an RTOG study awaiting drug availability.