Praxis soars on rare childhood epilepsy trial data
Marcio Souza, Praxis' president and chief executive.
Shares in Praxis Medicines rose more than 28% today after the company said it was halting a trial of its experimental therapy for rare childhood epilepsies early and preparing to file for approval.
The EMBOLD study of relutrigine (also known as PRAX-562) was testing the oral drug in patients with SCN2A and SCN8A developmental and epileptic encephalopathies (DEEs), and has been halted – on the advice of its data monitoring committee, after an interim analysis showed clear efficacy.
SCN2A and SCN8A are genes encoding voltage-gated sodium channels that play a key role in the firing of neurons, and mutations in them lead to DEEs associated with severe seizures, intellectual disability, and sometimes other symptoms like autism.
Relutrigine – a selective sodium channel modulator – is designed to block persistent and aberrant hyperexcitability caused by these so-called 'gain of function' mutations in the NaV1.2 and NaV1.6 channels.
"SCN2A and SCN8A DEEs are devastating conditions with extremely high mortality due to the debilitating seizure burden they impose on patients, and there are currently no approved treatment options," said Marcio Souza, Praxis' president and chief executive.
"Our progress represents an important milestone toward delivering the first therapy ever designed for these children and their families," he continued, noting that the data from EMBOLD will be shared at the American Epilepsy Society annual meeting, the 2025 edition of which gets underway today in Atlanta.
The rise in Praxis' share price to around $240 per share has swelled the company's valuation to more than $4.75 billion.
According to the Boston-based biopharma, the FDA has already confirmed a meeting to review the data and discuss next steps "in the coming weeks," and it will decide on the timing for a relutrigine filing after that takes place.
Last month, Praxis also reported what it said were positive results from a phase 3 trial of ulixacaltamide in essential tremor, although, questions have been raised about a change to the primary endpoint which, according to one short seller (PDF), has not been endorsed by the FDA.
Praxis also said it has now had a positive meeting with the FDA about an ulixacaltamide filing, which could take place early next year, and gives the company a path to having its first two commercial products, after its former lead drug for depression failed in 2022.
