One email when the decision is public, with what it means in plain language. You'll also get new trials and FDA news for the condition you pick. Unsubscribe anytime.
- Trial Alerts, when a new trial opens or a trial changes
- Disease Updates, FDA decisions and condition news, usually 1 or 2 emails a month
The FDA is expected to decide on Relutrigine for SCN2A and SCN8A developmental and epileptic encephalopathies by December 27, 2026, under an NDA from Praxis Precision Medicines.
What the FDA is deciding on Relutrigine for SCN2A Encephalopathy
The FDA is reviewing Praxis Precision Medicines' application to approve Relutrigine for SCN2A and SCN8A developmental and epileptic encephalopathies. Review extended 3 months from the original September date.
Who the Relutrigine decision matters to
SCN2A encephalopathy is a rare genetic epilepsy caused by a change in the SCN2A gene, which builds a sodium channel that brain cells use to fire. Depending on how the change alters the channel, a child may have seizures from the first days of life or may have autism and developmental delay with seizures starting later or not at all.
No approved drug targets the gene. Relutrigine, the first candidate, has an FDA decision due December 27, 2026, and an antisense drug called elsunersen is in a pivotal trial.
Prevalence: No reliable population count exists; the FamilieSCN2A Foundation describes SCN2A as a leading single-gene cause of infantile seizures, autism and intellectual disability, and estimates that about 75% of cases are still undiagnosed. See our full SCN2A Encephalopathy page for current treatments, recruiting trials, and community resources.
How Relutrigine works
Relutrigine: functional state-selective sodium channel modulator that preferentially inhibits the persistent sodium current leaking through overactive Nav1.2 and Nav1.6 channels. Our full Relutrigine profile covers how it works, side effects in plain language, and its trial history.
What an approval or a rejection of Relutrigine would mean
An approval starts a second race rather than ending the first one: specialty pharmacy setup, insurance review, and patient assistance typically take weeks even when everything goes right. Our guide to the 90 days after a rare disease approval explains the timeline and the moves families can make on day 1.
A complete response letter would mean the FDA declined to approve in the application's current form. The letter describes what the FDA wants addressed, and the company then decides whether to resubmit, run more studies or stop. Either way, this page updates with the outcome and what it means.
Where SCN2A Encephalopathy treatment stands today
Read our full SCN2A Encephalopathy treatment summary
No drug has been approved specifically for SCN2A encephalopathy, and the first decision is close. Relutrigine (PRAX-562), from Praxis Precision Medicines, is a small-molecule drug that dampens the persistent sodium current that overactive channels leak.
In the EMBOLD study, 51 patients with SCN2A or SCN8A encephalopathy who took relutrigine had 53% fewer seizures than placebo over 16 weeks, with no drug-related serious side effects, and an independent monitoring committee stopped the study early because the result was so clear.
The FDA accepted the application for priority review in March 2026 and then extended its review by 3 months after Praxis submitted additional analyses, moving the target date from September 27 to December 27, 2026; the company said the FDA requested no new studies and raised no safety or manufacturing concerns. If approved, it would be the first therapy for SCN2A and SCN8A encephalopathies.
A second approach, elsunersen (PRAX-222), is an antisense oligonucleotide designed to turn down production of the faulty channel, so it is meant only for gain-of-function cases. In the first part of its EMBRAVE study, 9 children aged 2 to 12 had 77% fewer monthly seizures than the sham-treated comparison, and 57% of treated children went at least 28 days seizure-free.
The FDA granted it Breakthrough Therapy designation in June 2026, and a pivotal single-arm study of about 30 patients (EMBRAVE3) is enrolling with results expected in 2027. Because these trials sort children by whether the variant is gain or loss of function, the single most useful thing a family can do before contacting a site is to have the variant's functional effect interpreted.
The FamilieSCN2A Foundation keeps a registry, a list of multidisciplinary clinics, and a running page of open studies.
The SCN2A Encephalopathy page has every treatment and trial →Meanwhile, 2 SCN2A Encephalopathy studies are open or about to open
Whatever the FDA decides here, research on SCN2A Encephalopathy does not stop. Of these, 1 tests a treatment; the others follow patients over time. The most recently updated:
We'll email you when the decision is public, with what it means in plain language, and when new trials open for the condition you pick. Unsubscribe anytime.
- Trial Alerts, when a new trial opens or a trial changes
- Disease Updates, FDA decisions and condition news, usually 1 or 2 emails a month
Frequently asked questions
When will the FDA decide on Relutrigine?
The FDA's target date (PDUFA date) for Relutrigine in SCN2A and SCN8A developmental and epileptic encephalopathies is December 27, 2026.
Who disclosed it: Praxis Precision Medicines. The FDA does not publish these dates.
Can it move: the FDA can act early, and a major amendment to the application can push the date back 3 months.
Source: Praxis press release
What is Relutrigine being reviewed for?
Praxis Precision Medicines submitted an NDA for Relutrigine in SCN2A and SCN8A developmental and epileptic encephalopathies.
What to know: Review extended 3 months from the original September date.
How it works: Functional state-selective sodium channel modulator that preferentially inhibits the persistent sodium current leaking through overactive Nav1.2 and Nav1.6 channels.
More: the Relutrigine drug page explains it in plain language.
Is there already an FDA-approved treatment for SCN2A Encephalopathy?
No. No medicine's current FDA label names SCN2A Encephalopathy, checked October 21, 2026.
Also coming: Elsunersen.
Check: the SCN2A Encephalopathy page also searches FDA drug labels for approved treatments.
What did the Relutrigine trials show?
EMBOLD (NCT05818553) is a Phase 2/3 study in children and young people aged 1 to 18 with early-onset SCN2A or SCN8A developmental and epileptic encephalopathy. In the double-blind part, participants were randomized to relutrigine for 16 weeks or to relutrigine for 12 weeks followed by 4 weeks of placebo, then continued into an open-label extension of up to 144 weeks.
More: the Relutrigine drug page has the full trial history and sources.
What are the side effects of Relutrigine?
In the EMBOLD study, Praxis reported no drug-related serious adverse events, and treatment-related adverse events were predominantly mild or moderate. The company has not published the rates of individual side effects in its announcements, and there is no US label yet, so the warnings and monitoring plan are not known.
More: the Relutrigine drug page has the safety details reported so far.
Can I get Relutrigine before the FDA decides?
Usually only through a clinical trial or an expanded access program, and the company decides whether to offer one.
Trials: 2 SCN2A Encephalopathy studies are open or about to open, 1 of them testing a treatment. See them.
Check your fit: Match Me compares your details with every open trial.
Expanded access: your doctor can ask Praxis Precision Medicines directly. Registered programs are listed on ClinicalTrials.gov.
How much will Relutrigine cost?
Praxis Precision Medicines has not announced a price. Drugmakers usually set it around approval.
Help paying: drugmaker programs and charity funds usually open at launch.
Find help: the patient assistance finder lists programs by insurance type.
What happens after the Relutrigine decision?
This page updates with the outcome the day it is announced.
If approved: getting the drug still takes time. Specialty pharmacy setup, insurance review and patient assistance often take weeks. Our guide covers what families can do on day 1.
If not approved: a complete response letter means the FDA declined the application in its current form. Many are about manufacturing or how data were presented, and companies often resubmit.
Where this date comes from
The FDA does not publish PDUFA dates; companies disclose them. This one comes from Praxis press release. Dates can move, and the FDA can act early or late. This page rechecks against our calendar, which is re-verified daily.