Fingolimod-associated macular edema

Abstract

Fingolimod (FTY-720), a sphingosine-1-phosphate receptor modulator, is the first US Food and Drug Administration (FDA)-approved oral agent for the treatment of relapsing forms of multiple sclerosis (MS). Two recent phase III clinical studies (TRANSFORMS [Trial Assessing Injectable Interferon vs FTY720 Oral in RRMS] and FREEDOMS [FTY720 Research Evaluating Effects of Daily Oral Therapy in MS]) demonstrated a significant reduction in the annualized relapse rate in patients with relapsing-remitting MS, compared to once weekly interferon β-1a and placebo. Macular edema was a prominent adverse event reported in these and prior studies of fingolimod. Thirteen of 2,564 (0.5%) patients treated with fingolimod in FREEDOMS and TRANSFORMS developed macular edema. Fingolimod-associated macular edema (FAME) appears to be dose-dependent (observed in only 2 patients taking the FDA-approved 0.5 mg dose) and typically resolves upon cessation of therapy. Although a relatively common condition in ophthalmology, most neurologists have not encountered macular edema in clinical practice. The purpose of this review is to educate the neurologist on the etiology, clinical manifestations, diagnostic modalities, and treatment approaches in patients with FAME. We also discuss the use of fingolimod in patients with uveitis and diabetes mellitus, highlight the guidelines for surveillance ophthalmic examination, and outline the key distinguishing features between FAME and optic neuritis.