The Japanese Ministry of Health, Labour and Welfare (MHLW) has granted orphan designation to Edison Pharmaceuticals’ EPI-743, an orally bioavailable small molecule, being developed for the treatment of Leigh syndrome in children.

Currently, EPI-743 is being evaluated in a randomised double-blind placebo-controlled Phase IIb trial to treat children with Leigh syndrome.

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A Phase IIb/III trial of EPI-743 is also being carried out in conjunction with Dainippon Sumitomo Pharm in Japan.

“EPI-743 is being evaluated in a randomised double-blind placebo-controlled Phase IIb trial to treat children with Leigh syndrome.”

The Japanese authority grants orphan status to drugs that are under development for treatment of rare conditions that are serious and difficult to treat and that have shown potential benefit for the indication.

Orphan status in Japan offers several advantages such as more expedited drug approval process, as well as a priority consultation with MHLW, the Japanese Pharmaceuticals and Medical Devices Agency (PMDA), and the Japanese National Institute of Biomedical Innovation (NIBIO).

The company had already secured orphan designation from the US Food and Drug Administration (FDA) to treat inherited respiratory chain diseases of the mitochondria and from the European Medicines Agency Committee on Orphan Products for treatment of Leigh syndrome.

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At present, there are no approved treatments for Leigh syndrome, which is an inherited lethal, progressive, predominately pediatric, neuromuscular disorder.

EPI-743 is developed by Edison to treat Leigh syndrome and other inherited mitochondrial diseases and it is a member of the para-benzoquinone class of drugs.

The company said that through a redox-based mechanism, EPI-743 augments endogenous glutathione biosynthesis-essential for the control of oxidative stress.

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