Praxis Medicines Wins Rare Disease and Orphan Drug Designations for DEEs

Author(s):

Including these agents for developmental and epileptic encephalopathies, the relatively young company has 5 programs under development to target rare neurological disorders.

Steven Petrou, PhD

The FDA has granted rare pediatric disease (RPD) and orphan drug designation (ODD) to PRAX-222 for the treatment of SCN2A developmental and epileptic encephalopathy (SCN2A-DEE), as well RPD to PRAX-562 for the treatment of SCN2A-DEE and for the treatment of SCN8A developmental and epileptic encephalopathy (SCN8A-DEE), both by Praxis Precision Medicines.¹

Both SCN2A-DEE and SCN8A-DEE are rare DEEs caused by variants in the SCN2A and SCN8A genes that disrupt the formation of sodium channel proteins in the brain and therefore the flow of sodium to neurons.

“The potential broad utility of PRAX-562 in DEEs and other rare [central nervous system] CNS disorders and the precision therapy approach of PRAX-222 represent two differentiated and potentially complementary treatment paradigms inspired by human genetics,” said Steven Petrou, PhD, co-founder and chief scientific officer, Praxis Precision Medicine, in a statement. “The FDA granting these designations is an acknowledgement of the critical need to develop treatments for children living with these devastating diseases.”

PRAX-222 is an antisense oligonucleotide designed to lower the expression of the protein encoded by the SCN2A gene in patients with SCN2A gain-of-function epilepsy. The treatment is currently being investigated in IND-enabling studies.

PRAX-562, a selective small molecule, is the first persistent sodium current blocker in development. It is intended to treat a wide range of rare CNA disorders. It is currently being investigated in a phase 1 clinical trial in adult healthy volunteers. The treatment will be investigated in proof-of-concept trials in 2 rare types of cephalgia, as well as investigated in additional rare pediatric DEEs.

“As a company deeply rooted in the genetic drivers of severe pediatric epilepsies, these designations are especially meaningful and validating,” added Marcio Souza, president and chief executive officer, Praxis Precision Medicines. “We are committed to drug development for both common and rare CNS diseases and look forward to progressing PRAX-562 and PRAX-222 in the clinic and ultimately to children who are in dire need of new treatment options.”

Praxis Precision Medicines aims to develop medications that target atypical mechanisms shared by many neurological disorders. Although they began looking at the genetics of epilepsy, “what became clear pretty quickly is the pathway for epilepsy addresses other diseases,” as Souza said in a prior statement.²

The company formed in May 2020, and soon after added $110 million in funding to develop medications for rare central nervous system (CNS) diseases. Praxis currently has 5 programs in development to address such CNS diseases, including SCN2A-DEE and SCN8A-DEE, 3 of which are in the development pipeline for regulation.³

“Recent genetic insights have presented meaningful opportunities to treat brain disorders in entirely different and targeted ways based on the specific genetically validated pathways driving a patient’s disease,” Kiran Reddy, co-founder and board member, Praxis Precision Medications, said in a statement addressing the funding. “We are reducing these insights to practice, to create novel medicines that could fundamentally alter the treatment path and outcomes for patients with brain disorders.”

REFERENCES

1. Praxis Precision Medicines receives rare pediatric disease and orphan drug designations for severe pediatric epilepsy programs. News release. Praxis Precision Medicines. Published online January 7, 2021. Accessed January 18, 2021. https://www.globenewswire.com/news-release/2021/01/07/2154881/0/en/Praxis-Precision-Medicines-Receives-Rare-Pediatric-Disease-and-Orphan-Drug-Designations-for-Severe-Pediatric-Epilepsy-Programs.html
2. Vinluan F. Backed by $100M, Praxis aims to turn epilepsy research into new neuro drugs. Xconomy. Published online May 4, 2020. Accessed January 18, 2021. https://xconomy.com/boston/2020/05/04/backed-by-100m-praxis-aims-to-turn-epilepsy-research-into-new-neuro-drugs/
3. DeFeudis N. Praxis raises $110 million to target CNS disease with Phase II drugs. Endpoints News. Published online July 28, 2020. Accessed January 18, 2021. https://endpts.com/praxis-raises-110-million-to-target-cns-disease-with-phase-ii-drugs/