Clinical experience of human leucocyte interferon in the management of herpetic keratitis

A series of 78 patients was admitted to the trial. All the ulcers healed within 48 hours, the majority in 24 hours. In the placebo group 49 per cent developed focal recurrences. Of those receiving the low dose interferon (11 x 10⁶ unit/ml) 30 per cent developed lesions, and in the high dose group (33 x 10⁶ unit/ml) 20 per cent showed evidence of viral activity. The difference between the recurrence rate in the placebo groups and the interferon high dose groups is not likely to have occurred by chance, for a χ² test gives a P value of <0.05. Careful examination of the external eye failed to reveal any evidence of untoward reaction to the drug, nor did any patient develop stromal disease. It is too early to assess any effect on recurrence rates.