Herpes Stromal Keratitis, on Steroid Treatment (HEDS-SKS): Patients with active HSV stromal keratitis who already were being treated with a topical corticosteroid were randomized either to oral treatment with 200 mg acyclovir capsules (400 mg five times daily) for 10 weeks or to the identical dose of placebo capsules. Patients also received topical prednisolone phosphate in the dosage schedule described above for the SKN trial.