A rare disease, a rare chance. FDA fast-tracks idebenone for LHON.
The U.S. Food and Drug Administration (FDA) doesn’t hand out Priority Reviews lightly. But idebenone (Chiesi Global Rare Diseases; Massachusetts, United States) just made the cut, moving one step closer to becoming the first FDA-approved treatment for Leber hereditary optic neuropathy (LHON). The agency has set a target decision date of February 28, 2026.
If greenlit, idebenone would finally give U.S. patients a therapy for this sudden and debilitating mitochondrial condition. The drug is already marketed as Raxone in the European Union, United Kingdom, Israel, South Korea and several other regions.
“LHON changes lives in an instant. This review brings hope of the first-ever approved treatment in the U.S. for LHON, one of the most prevalent mitochondrial diseases,” said Malinda Marsh, Chris Marsh and Lissa Poincenot, co-founders of the LHON Collective and parents of children affected by the disorder.
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LHON 101
LHON is driven by mitochondrial dysfunction in retinal ganglion cells, leading to rapid central vision loss. Typically, it strikes young men between 15 and 35 years of age and is estimated to affect one in 15,000 to 50,000 people worldwide.
“LHON is a serious condition marked by rapid central vision loss, often beginning in one eye and quickly affecting the other, placing a profound and immediate burden on patients and their loved ones,” said Dr. Nancy Newman, LeoDelle Jolley Chair of Ophthalmology at Emory University School of Medicine. “If approved in the United States, idebenone would represent a meaningful advancement in treatment, offering hope to the LHON community.”
Clinical evidence on the table
The FDA filing includes data from both the Phase III RHODOS and Phase IV LEROS trials. In RHODOS, idebenone showed statistically significant improvements in several visual acuity measures compared to placebo.
In LEROS, 42.3% of treated eyes achieved a “clinically relevant benefit” at 12 months, compared with just 20.7% in a matched natural history cohort.
As for safety, the most commonly reported adverse reactions—mild to moderate and reversible—included increases in alanine aminotransferase, diarrhea and increases in aspartate aminotransferase.
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Chiesi’s perspective
“For years we have been proud to provide idebenone to individuals outside the U.S. living with LHON,” said Mitch Goldman, senior vice president of R&D at Chiesi. “Now we are eager for the opportunity to introduce this clinically proven therapeutic option to the U.S., giving hope where there has been none.”
Chiesi Global Rare Diseases, a unit of the Chiesi Group, has worked closely with the FDA’s Division of Ophthalmology throughout the submission process.
It’s still months before the FDA issues its decision, but the mood is cautiously optimistic. If idebenone crosses the finish line, a condition once met with clinical shrugs may finally get its first U.S. treatment nod.
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Editor’s Note: More information can be found here. This content is intended exclusively for healthcare professionals. It is not intended for the general public. Products or therapies discussed may not be registered or approved in all jurisdictions, including Singapore.