The effects of local and systemic interferon beta (Fiblaferon) on supratentorial malignant cerebral glioma--a phase II study.

In contrast to the highly promising and, with rates up to 40%, surprisingly high response rates of malignant supratentorial brain gliomas to post-operative adjuvant IFN beta therapy, we were unable to demonstrate any definite anti-proliferative, anti-tumor or immunomodulatory effects of interferon in a phase II study in 13 patients. We used high doses of an IFN beta, Fiblaferon, whose potency was repeatedly confirmed by pharmacokinetic investigations, for local and systemic administration, and the times of administration were those used in the Japanese comparative studies. The side effects observed proved to be related to the amount of IFN beta administered and its duration in our patients as well. In this context, the neurotoxic disturbances require particular attention. These resolved completely after discontinuation of IFN treatment, as do the haematological and liver enzyme disturbances after suspension of medication. We did not observe any improvement in the post-operative quality of life, nor, above all, any improvement in long-term prognosis resulting from a prolonged tumor-free remission period and prolongation of the actual post-operative survival time.