Therapeutic effect of human fibroblast interferon on premalignant lesions arising in oral mucosa

Human fibroblast interferon (HuIFN-β) was topically administered to 20 premalignant lesions histopathologically showing epithelial dysplasia such as leukoplakia and lichen planus which arose in the oral mucosa. HuIFN-β was prepared in the water-soluble gel form containing 2% carboxymethylcellose, 45% glycelin, 0.1 M citrate buffer (pH 4.5) and 0.2% SDS as stabilizing agents. This preparation was found to be effective for herpetic gingivostomatitis and zostal lesions arising along the intercostal nerve. Thus, the HuIFN-β preparation (10⁴ to 5 × 10³ IU) was applied to the oral mucosal lesion for 1 h twice a week. The lesion with topical administration of HulFN-β was covered tightly with the mucosal bandage which was coated with carboxymethylcellulose, glycelin and CaCl₂ on vinyl acetate matrix. The 14 oral lesions with erosion or ulcer formation accompanied by severe pain by touch, had complete remission after approximately 10 successive applications of this preparation. Although subjective symptoms such as irritation pain in the other 6 patients with severe hyperkeratotic lesion subsided, white coatings and streaks could not be completely removed by this therapy. No other side-effects excluding slight pain and reddish swelling which occurred intermittently during HuIFN-β administration were observed.