This section highlights FDA-related milestones and regulatory updates for drugs developed by Praxis Precision Medicines (PRAX).
Over the past two years, Praxis Precision Medicines has reported clinical trial outcomes, regulatory submissions, approvals, and other FDA events for drugs and therapies such as
PRAX-222, elsunersen, Relutrigine, PRAX-562, PRAX-562, and Ulixacaltamide. For definitions of regulatory abbreviations such as NDA, BLA, or PDUFA, see the event status legend.
Select a button below to view the list of FDA events for that drug.
PRAX-222 FDA Regulatory Events
PRAX-222 is a drug developed by Praxis Precision Medicines for the following indication: For Treatment of SCN2A Gain of Function Developmental Epilepsies.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- PRAX-222
- Announced Date:
- June 22, 2026
- Indication:
- For Treatment of SCN2A Gain of Function Developmental Epilepsies
Announcement
Praxis Precision Medicines, Inc announced that the U.S. Food and Drug Administration (FDA) has granted BTD for elsunersen (PRAX-222), an antisense oligonucleotide (ASO) for the treatment of seizures associated with SCN2A Developmental and Epileptic Encephalopathy (SCN2A-DEE) caused by Gain of Function (GoF) variants in SCN2A..
AI Summary
Praxis Precision Medicines said the FDA granted Breakthrough Therapy Designation to elsunersen (PRAX-222), an antisense oligonucleotide being tested for seizures linked to SCN2A Developmental and Epileptic Encephalopathy (SCN2A-DEE) caused by gain-of-function variants in the SCN2A gene. The designation was based on results from the EMBRAVE Part A trial, where elsunersen showed a 77% sham-adjusted drop in monthly seizures, with benefits lasting up to one year in the open-label extension. The company said its pivotal EMBRAVE3 study is now moving forward through a streamlined, single-arm registrational pathway agreed on with the FDA. The trial will enroll about 30 patients and measure changes in countable motor seizures after 24 weeks of treatment. Praxis noted that no approved treatments currently address the underlying genetic cause of this rare, severe epilepsy.
Read Announcement
Elsunersen FDA Regulatory Events
Elsunersen is a drug developed by Praxis Precision Medicines for the following indication: Patients with SCN2A Early-Onset Developmental and Epileptic Encephalopathy.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- elsunersen
- Announced Date:
- April 6, 2026
- Indication:
- Patients with SCN2A Early-Onset Developmental and Epileptic Encephalopathy
Announcement
Praxis Precision Medicines, Inc. announced positive topline results from the EMBRAVE Part A trial of elsunersen in pediatric patients with early-seizure onset SCN2A developmental and epileptic encephalopathy (DEE).
AI Summary
Praxis Precision Medicines announced positive topline results from the EMBRAVE Part A trial of elsunersen in pediatric patients with early‑seizure onset SCN2A developmental and epileptic encephalopathy (DEE). Elsunersen showed a placebo‑adjusted seizure reduction from baseline of 77% (p=0.015). By period 6, 71% of elsunersen‑treated patients achieved more than a 50% seizure reduction, with sustained benefit seen in the open‑label extension for up to one year.
All elsunersen patients (100%) — and none on placebo — had additional clinical improvements, including better sleep, motor function, muscle tone and attention. The drug was well tolerated: no treatment‑emergent or serious adverse events were judged related to the study drug, there were no discontinuations, and no neuroinflammation signals were observed at doses up to 8 mg. Most adverse events were mild to moderate and consistent with prior study data.
Praxis said it is progressing to its pivotal EMBRAVE3 study and will share more results at upcoming scientific meetings.
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Relutrigine FDA Regulatory Events
Relutrigine is a drug developed by Praxis Precision Medicines for the following indication: Patients with SCN2A and SCN8A DEEs.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- Relutrigine
- Announced Date:
- March 30, 2026
- Indication:
- Patients with SCN2A and SCN8A DEEs
Announcement
Praxis Precision Medicines, Inc. announced that the U.S. Food and Drug Administration (FDA) has accepted for priority review its New Drug Application (NDA) for relutrigine, for the treatment of SCN2A and SCN8A developmental and epileptic encephalopathies (DEEs).
AI Summary
Praxis Precision Medicines announced that the U.S. Food and Drug Administration has accepted for priority review its New Drug Application (NDA) for relutrigine, an investigational treatment for SCN2A and SCN8A developmental and epileptic encephalopathies (DEEs). Priority review signals the FDA will review the application faster than usual because the drug could address an unmet medical need for these rare, severe seizure disorders.
The FDA assigned a PDUFA target action date of September 27, 2026. Relutrigine is also being studied more broadly in DEEs through the ongoing EMERALD trial, which the company expects to complete by the end of 2026. Results from EMERALD could inform broader use if the drug is approved.
This regulatory milestone and the trial timeline are important steps for patients, families, and clinicians seeking new treatment options for SCN2A- and SCN8A-related DEEs. Further safety and efficacy data will determine next steps.
Read Announcement- Drug:
- Relutrigine
- Announced Date:
- March 30, 2026
- Indication:
- Patients with SCN2A and SCN8A DEEs
Announcement
Praxis Precision Medicines, Inc. announced that the FDA has set a target action date under the Prescription Drug User Fee Act (PDUFA) of September 27, 2026.
AI Summary
Praxis Precision Medicines said the U.S. Food and Drug Administration has set a Prescription Drug User Fee Act (PDUFA) target action date of September 27, 2026 for relutrigine. This means the FDA aims to complete its review and issue a decision on the company’s submission by that date. A PDUFA target gives investors, clinicians, and patients a timeline for when regulatory action—such as approval, a request for more data, or other regulatory outcomes—may occur.
Praxis also notes relutrigine is being tested in a broad program for developmental and epileptic encephalopathies (DEEs) through the EMERALD trial, which is expected to finish by the end of 2026. Results from EMERALD could inform the FDA review and help determine the drug’s potential role for patients with DEEs. Stakeholders will be watching both the trial readout and the PDUFA decision next year.
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PRAX-562 (SCN2A) FDA Regulatory Timeline and Events
PRAX-562 (SCN2A) is a drug developed by Praxis Precision Medicines for the following indication: CN2A development and epileptic encephalopathy (SCN2A-DE.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- PRAX-562 (SCN2A)
- Announced Date:
- December 11, 2025
- Indication:
- CN2A development and epileptic encephalopathy (SCN2A-DE
Announcement
Praxis Precision Medicines, Inc. announced the successful completion of the planned discussion with the FDA leading to the confirmation to file a New Drug Application (NDA) for relutrigine in early 2026.
AI Summary
Praxis Precision Medicines said it completed a planned discussion with the FDA that confirmed the company can file a New Drug Application (NDA) for relutrigine in early 2026. Company leadership described the talks as collaborative and said the agreement supports their planned timeline for submission and continued development. The decision marks a key regulatory step toward potential approval and broader access to the medicine for affected patients.
Relutrigine is a first‑in‑class small molecule being developed to treat developmental and epileptic encephalopathies (DEEs) by preferentially inhibiting persistent sodium current linked to seizures. Clinical data from the EMBOLD study showed statistically significant and clinically meaningful reductions in motor seizures and a generally well‑tolerated safety profile. Praxis said these results, together with preclinical and early clinical findings, underpin its readiness to move ahead with the NDA filing in early 2026. The company is preparing the submission and next regulatory steps.
Read Announcement- Drug:
- PRAX-562 (SCN2A)
- Announced Date:
- July 17, 2025
- Indication:
- CN2A development and epileptic encephalopathy (SCN2A-DE
Announcement
Praxis Precision Medicines, Inc. announced that the U.S. Food and Drug Administration (FDA) has granted BTD for relutrigine, a sodium channel functional state modulator for pediatric use for the treatment of patients with SCN2A and SCN8A DEEs.
AI Summary
Praxis Precision Medicines, Inc. announced that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation (BTD) for relutrigine, a sodium channel functional state modulator. This designation is for its use in pediatric patients suffering from SCN2A and SCN8A developmental and epileptic encephalopathies (DEEs). The decision was based on highly promising results from the Phase 2 EMBOLD trial, where relutrigine demonstrated impressive seizure reduction and extended seizure-free periods in a particularly severe patient group.
The BTD is an important milestone, as it speeds up the development and review process for treatments showing significant improvements over current therapies. This development supports Praxis’s commitment to fast-track effective therapies for children with these challenging epileptic conditions, offering hope for better management and improved quality of life for patients and their families.
Read Announcement- Drug:
- PRAX-562 (SCN2A)
- Announced Date:
- September 2, 2024
- Indication:
- CN2A development and epileptic encephalopathy (SCN2A-DE
Announcement
Praxis Precision Medicines announced that it will share the topline results from the Phase 2 EMBOLD study of relutrigine (PRAX-562) in SCN2A,
AI Summary
Praxis Precision Medicines announced that it will share the topline results from the Phase 2 EMBOLD study of relutrigine (PRAX-562) focused on patients with SCN2A-related conditions. The study is part of the company’s efforts to explore potential treatments for severe developmental epileptic encephalopathies (DEEs) caused by mutations in SCN2A and SCN8A. The topline data will be released on Tuesday, September 3, 2024, just before the market opens. After the announcement, Praxis will host a conference call and webcast at 8:00 a.m. ET to discuss the trial results. This update is a key step in Praxis’s mission to translate genetic findings into therapies aimed at restoring the balance between neuronal excitation and inhibition in the brain, potentially offering new hope for patients with difficult-to-treat CNS disorders.
Read Announcement
PRAX-562 (SCN8A) FDA Regulatory Events
PRAX-562 (SCN8A) is a drug developed by Praxis Precision Medicines for the following indication: SCN8A development and epileptic encephalopathy (SCN8A-DEE).
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- PRAX-562 (SCN8A)
- Announced Date:
- July 17, 2025
- Indication:
- SCN8A development and epileptic encephalopathy (SCN8A-DEE)
Announcement
Praxis Precision Medicines, Inc. announced that the U.S. Food and Drug Administration (FDA) has granted BTD for relutrigine, a sodium channel functional state modulator for pediatric use for the treatment of patients with SCN2A and SCN8A DEEs.
AI Summary
Praxis Precision Medicines, Inc. announced that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation (BTD) for relutrigine. This drug is a sodium channel functional state modulator being developed for pediatric patients with SCN2A and SCN8A developmental and epileptic encephalopathies (DEEs). The designation was supported by promising data from the Phase 2 EMBOLD trial. In this study, patients with severe DEEs, who had not responded to multiple previous treatments, experienced significant clinical improvements. Early results showed an average 90% reduction in seizures and longer seizure-free intervals, offering hope for better quality of life for patients and their caregivers.
The BTD allows for expedited development and regulatory review. Praxis is planning further studies, including the ongoing registrational EMBOLD cohort 2 and the EMERALD study, to confirm the benefits of relutrigine in treating these rare and challenging conditions.
Read Announcement- Drug:
- PRAX-562 (SCN8A)
- Announced Date:
- September 2, 2024
- Indication:
- SCN8A development and epileptic encephalopathy (SCN8A-DEE)
Announcement
Praxis Precision Medicines announced that it will share the topline results from the Phase 2 EMBOLD study of relutrigine (PRAX-562) in SCN8A
AI Summary
Praxis Precision Medicines announced that it will share the topline results from its Phase 2 EMBOLD study evaluating relutrigine (PRAX-562) in patients with SCN8A Developmental and Epileptic Encephalopathies (DEEs). The study examines the potential of relutrigine to address imbalances in neuronal excitation and inhibition, which are central to these severe neurological disorders. This announcement is scheduled for Tuesday, September 3, 2024, before the market opens, with further details to be provided during a conference call and webcast at 8:00 a.m. ET.
The information from the study is eagerly anticipated as researchers and investors look forward to understanding how relutrigine may benefit patients with SCN8A-associated conditions. The initiative highlights Praxis Precision Medicines' commitment to translating genetic insights into treatments for central nervous system disorders and improving care for those affected by these challenging conditions.
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Ulixacaltamide Essential1 FDA Regulatory Events
Ulixacaltamide Essential1 is a drug developed by Praxis Precision Medicines for the following indication: Designed to block abnormal neuronal burst firing in the Cerebello-Thalamo-Cortical (CTC) circuit correlated with tremor activity and being developed for Essential Tremor.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- Ulixacaltamide Essential1
- Announced Date:
- September 26, 2024
- Indication:
- Designed to block abnormal neuronal burst firing in the Cerebello-Thalamo-Cortical (CTC) circuit correlated with tremor activity and being developed for Essential Tremor.
Announcement
Praxis Precision Medicines, Inc. announced the presentation of a poster and platform talk showcasing its Phase 3 clinical program evaluating ulixacaltamide for adults with essential tremor (ET) at the Movement Disorders Society (MDS) 2024 International Congress taking place in Philadelphia, Pennsylvania, September 27 – October 1, 2024.
AI Summary
Praxis Precision Medicines announced that it will present a poster and give a platform talk at the Movement Disorders Society (MDS) 2024 International Congress. The event will be held in Philadelphia, Pennsylvania, from September 27 to October 1, 2024. The presentations will focus on the company’s Phase 3 clinical program evaluating ulixacaltamide, a new therapy for adults with essential tremor (ET). Ulixacaltamide is designed to work by blocking abnormal neuronal burst firing in the brain, aiming to reduce tremor activity. The platform talk and poster presentation will share important progress and insights from the clinical program, and attendees can learn more about the science behind the therapy. This opportunity highlights Praxis Precision Medicines' dedication to developing treatments for central nervous system disorders and advancing innovative solutions to improve patient quality of life.
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