Unfortunately, it can sometimes be difficult to get companies to perform research and develop therapeutics for rare diseases, but the FDA came up with a process to spur research and development through incentivization. Orphan Drug designation is granted to drugs or biologics intended to treat, diagnose, or prevent rare diseases – those affecting under 200,000 Americans. As a benefit, the drug developer receives tax credits, fee waivers, increased regulatory assistance, and seven years of market exclusivity upon approval. According to a press release from biopharmaceutical company Epygenix Therapeutics (“Epygenix”), the company’s product EPX-100 recently earned Orphan Drug designation for Ohtahara syndrome.
What is Ohtahara Syndrome?
The Neurology blog describes Ohtahara syndrome as:
an early infantile epileptic encephalopathy characterized by frequent tonic spasms within the first three months of life. EEG shows a suppression-burst pattern in both sleep and wakeful periods.
In some cases, Ohtahara syndrome may be misdiagnosed as early myoclonic encephalopathy. One way to distinguish the conditions is seizure types. For example, those with Ohtahara syndrome do not typically have myoclonic seizures. Doctors are not sure exactly what causes Ohtahara syndrome in all cases. However, congenital cortical malformations and STXBP1 gene mutations have been associated with this condition. Symptoms and characteristics include treatment-resistant seizures, as well as severe developmental delays in those who survive through childhood and beyond.
EPX-100: An Exploration
Also known as clemizole hydrochloride, EPX-100 is a first-generation antihistamine that Epygenix says was safely used from the 1950s-1970s. This treatment is being evalauted to treat a wide variety of rare genetic epilepsies. For example, Epygenix is also evaluating EPX-100 as a potential treatment for Dravet syndrome and Lennox-Gastaut syndrome, and has received other designations for those indications. According to Epygenix:
EPX-100’s antiepileptic action is not through a histaminergic mechanism of action but acts via modulation of serotonin (5HT) signaling pathways.
Prior studies of EPX-100, performed in non-human models, showed that the treatment was effective in reducing seizures and related symptoms. Additionally, in human studies, EPX-100 was found to be relatively safe and well-tolerated.
