LOCAL INJECTION OF OK-432 FIBRINOGEN GEL INTO HEAD AND NECK CARCINOMAS/

Immunotherapy with biological response modifiers (BRM) is a possible s trategy against head and neck solid tumours. However, the rapid disapp earance of BRM from the tumour area is one of the reasons for its limi ted clinical application. In this pilot study, fibrinogen gel containi ng OK-432 (a compound composed of attenuated Streptococcus pyogenes), an inducer of natural killer cells and T-cell cytotoxity, was injected directly into head and neck solid tumours of 15 patients. A dose of 5 Klinische Einheiten (KE) of OK-432 was reconstituted in 1 ml aprotini n and mixed with fibrinogen, the latter to maintain the OK-432 locally . 3 patients showed tumour regression, and in addition, we observed hi stological changes in the injected tumour of all patients. These resul ts suggest that OK-432/fibrinogen gel generates a local immune respons e, leading to tumour regression.