Interferon Alfa-associated Anterior Ischemic Optic Neuropathy

Purpose To report a possible association between interferon alfa therapy and anterior ischemic optic neuropathy (AION). Design Database study and review of the literature. Participants Thirty-six case reports from spontaneous reporting systems and the literature. Methods Case reports from a review of the literature were combined with spontaneous reports from the National Registry of Drug-Induced Ocular Side Effects, the World Health Organization, and the Food and Drug Administration looking for reports on interferon therapy associated with optic neuropathy. Main Outcome Measures Data from the spontaneous reports include the type of interferon, age, gender, adverse drug reaction (ADR), dosage, duration of therapy until onset of ADR, concomitant drugs, systemic disease, and dechallenge and rechallenge data. Results Thirty-six case reports of AION are described in association with interferon alfa therapy. The average age of subjects was 54.5 years; 26 were male and 10 were female. The median duration of therapy to onset of AION was 4.5 months, with 50% of subjects having some form of permanent vision loss. Anterior ischemic optic neuropathy was bilateral in 67% of subjects. There are 3 positive rechallenge case reports. Conclusions Interferon alfa's association with AION can be classified as “possible” using the World Health Organization classification system. If optic neuropathy is suspected, rapid cessation of interferon therapy may portend a better prognosis because multiple case reports indicate visual defects may be permanent if this possible ADR remains unrecognized. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references.