FDA Grants Rare Pediatric Disease Designation to Khondrion Ahead of Program Expiration

Rare Daily Staff

The U.S. Food and Drug Administration granted Rare Pediatric Disease designation to Khondrian’s sonlicromonal for the treatment of patients with MELAS syndrome, just two days before expiration of the designation program.

MELAS is an acronym for mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes. It belongs to a clinical spectrum of mitochondrial diseases most frequently caused by a mutation in the MT-TL1 gene in mitochondrial DNA. MELAS syndrome begins in childhood, usually between the ages of two and fifteen years, with approximately 75 percent of cases reporting an onset of the disorder before the age of 20 years. Although rare, it is one of the most common types of mitochondrial diseases caused by mutations in the mtDNA, with an estimated prevalence for MELAS spectrum disorders in adults and children of risk of 4.4 in 100,000 people.

MELAS syndrome is a progressive and often early fatal disorder affecting organs and tissues with a high-energy demand, such as the brain and skeletal muscle. Current existing therapies only manage the symptoms and don’t target the underlying cause of the disease.

Jan Smeitink, founder and CEO at Khondrion said the designation “signals the FDA’s recognition that MELAS syndrome presents a serious and unmet medical need and highlights the potential of sonlicromanol to become the first disease-modifying treatment for this devastating mitochondrial disease.”

Sonlicromanol is a potentially first-in-class oral small molecule in development for the treatment of mitochondrial disease. It has already been granted Orphan Drug designations for MELAS, Leigh disease, and patients with maternally inherited diabetes and deafness (MIDD) syndrome in Europe, and for all inherited mitochondrial respiratory chain disorders in the United States.

A phase 2b study of sonlicromanol in MELAS spectrum disorders is currently ongoing across a number of internationally recognized mitochondrial disease centers in Europe. Khondrion intends to submit a pre-IND (Investigational New Drug) request in the short term to further discuss the development plan for sonlicromanol in the United States.

The FDA grants Rare Pediatric Disease designation for serious or life-threatening diseases with manifestations in individuals aged from birth to 18 years, including access to the FDA’s expedited review and approval process. The designation makes sonlicromanol eligible for a Rare Pediatric Disease Priority Review voucher upon approval of the therapy by the FDA. There are no approved therapies for MELAS.

The vouchers can be used to reduce the time of an FDA new drug approval review to six months from ten months. The vouchers are potentially lucrative because they are transferable. Most recently, Sarepta sold its priority review voucher to Vifor Pharma $111 million in February 2020.

Though the program is due to expire at the end of the month, a drug that has been granted RPD designation prior to this date is still eligible to receive the voucher if it receives final FDA approval before September 30, 2022. There is also legislation that has been introduced to extend the program.

Photo: Jan Smeitink, founder and CEO at Khondrion