Enhanced production of gamma-interferon by therapy with parenteral OK-432 and alpha-interferon in patients with head and neck cancer.

Although the drug OK-432 can induce the release of gamma-interferon (IFN-gamma), the serum concentrations of IFN-gamma produced are very low. We studied the effects of combining OK-432 with alpha-interferon (IFN-alpha) on the endogenous production of IFN and the postoperative courses of patients with oral cavity cancers. Forty patients operated on for head and neck cancers were studied. Each patient was given an injection of OK-432 1 week after surgery. Between 10 and 14 days later, a combination of OK-432 and IFN-alpha was given to assess the effects of the concomitant use of IFN-alpha on IFN production. In 18 of the 30 patients given a large dose of IFN-alpha (3 or 5 X 10(6) IU/mg protein), IFN production induced by OK-432 was enhanced. A small dose of IFN-alpha (7 X 10(3) IU) did not enhance the action of OK-432. OK-432 also induced the release of both endogenous IFN-gamma and IFN-alpha, and the production of both types of IFN was enhanced by the concomitant administration of parenteral IFN-alpha. Next, 50 patients operated on for oral cavity cancers were given OK-432 or a combination of OK-432 and IFN-alpha for 4 months, and their postoperative courses were followed for 2-5 years. The clinical courses were better in the combined therapy group than in the group given OK-432 alone.