Topical treatment with nerve growth factor for neurotrophic keratitis

Abstract

Objective To evaluate the efficacy of nerve growth factor (NGF) in patients with neurotrophic keratitis. Design Prospective, noncomparative, interventional case series. Participants Forty-five eyes of 43 consecutive patients with moderate (stage 2, n = 17) to severe (stage 3, n = 28) neurotrophic keratitis unresponsive to other nonsurgical therapies. Methods After a 10-day washout with preservative-free artificial tears, 45 eyes with neurotrophic keratitis received murine NGF (200 μg/ml) every 2 hours for 2 days followed by one drop six times daily until the ulcer healed. A maintenance dose of one drop NGF (100 μg/ml) was administered four times daily for the 2 weeks subsequent to ulcer healing. Main outcome measures Size and depth of the ulcer or the epithelial defect, corneal sensitivity, best corrected visual acuity, side effects, and relapse of the disease in the follow-up period. Results All patients had a complete resolution of the persistent epithelial defect (with or without an ulcer) after 12 days to 6 weeks of treatment with NGF. Patients affected by both stages of the disease demonstrated both improved corneal sensitivity and visual acuity (P < 0.001). No significant differences were observed in the time to complete corneal healing between stage 2 and stage 3 patients. Hyperemia and ocular and periocular pain were side effects reported during the first days of treatment. No relapse of the disease was observed during the follow-up period, with the exception of three patients with trigeminal nerve resection, who required a single retreatment. Conclusions Nerve growth factor eye drops improved corneal sensitivity and promoted corneal epithelial healing in both moderate and severe neurotrophic keratitis. Although performed in an uncontrolled and nonrandomized series of patients, this therapy shows promise for the restoration of ocular surface integrity and visual function in neurotrophic corneal disease.