SK Biopharmaceuticals Submits Supplemental New Drug Application to U.S. FDA for Cenobamate

Application seeks indication for primary generalized tonic-clonic (PGTC) seizures and expansion of existing focal-onset seizure indication to pediatric patients

- Submission supported by results from a global Phase 3 trial evaluating the efficacy and safety of cenobamate in patients with PGTC seizures
- A separate sNDA also seeks to expand the existing focal-onset seizure indication to pediatric patients
- Submission advances SK Biopharmaceuticals' ongoing development program evaluating cenobamate across additional seizure types and age groups

PARAMUS, N.J., Nov. 4, 2026 /PRNewswire/ -- SK Biopharmaceuticals today announced that it has submitted a supplemental New Drug Application (sNDA) to the U.S. Food and Drug Administration (FDA) seeking approval of cenobamate (U.S. brand name: XCOPRI^®) for the treatment of primary generalized tonic-clonic seizures (PGTC) and an expansion of the existing focal-onset seizure (FOS) indication to include pediatric patients.

"This submission represents an important step in our continued investment in cenobamate and our efforts to reach more people living with epilepsy," said Donghoon Lee, CEO of SK Biopharmaceuticals. "We are building on the foundation established with cenobamate in focal-onset seizures in adults by evaluating its potential in additional seizure types, age groups and formulations. Our goal is to continue advancing innovation that can provide physicians with more treatment options to address the diverse needs of people living with epilepsy."

The sNDA is supported by positive results from a global Phase 3 trial (NCT03678753) evaluating cenobamate in patients 12 years of age and older living with PGTC seizures. The trial enrolled 169 patients across 122 sites in 12 countries, including the U.S., South Korea and countries in Europe.

In the trial, patients treated with cenobamate experienced a median 71.9% reduction in PGTC seizure frequency from baseline compared with a 39.6% reduction among patients receiving placebo, a statistically significant difference (p=0.003). Most reported adverse events were mild to moderate, and the safety findings were consistent with the known safety profile of cenobamate, with no new safety signals observed.

If approved by the FDA, the new indication would expand the use of cenobamate beyond its current indication for focal-onset seizures in adults and provide an additional treatment option for eligible patients with PGTC seizures. The PGTC submission is part of SK Biopharmaceuticals' broader effort to evaluate cenobamate across additional patient populations and formulations.

SK Biopharmaceuticals also submitted a separate sNDA to the FDA in October seeking to expand the existing focal-onset seizure (FOS) indication to pediatric patients. The company confirmed cenobamate's safety in clinical trials in pediatric patients with FOS and is pursuing an expansion of the eligible age range on that basis.

The company also submitted a New Drug Application (NDA) to the FDA in March for an oral suspension formulation of cenobamate. The formulation would provide an alternative for patients who have difficulty swallowing tablets and was also used in the pediatric clinical trial program.

Since the launch of XCOPRI in the U.S. in 2020, SK Biopharmaceuticals has continued to invest in the development of cenobamate with the goal of addressing the needs of more people living with epilepsy. These efforts include evaluating cenobamate in additional seizure types and age groups, developing additional formulations and expanding its availability in markets around the world.

SK Life Science, Inc., based in Paramus, New Jersey, is a U.S. subsidiary of SK Biopharmaceuticals Co., Ltd., a global biopharmaceutical company headquartered in South Korea that focuses on developing and commercializing innovative treatments. Together, they are advancing innovative treatments for central nervous system (CNS) disorders and expanding into oncology through next-generation modalities, including radiopharmaceutical therapy (RPT) and targeted protein degradation (TPD), while leveraging AI-driven innovation to accelerate drug development and enhance patient care. For more information, visit sklifescienceinc.com.

SK Biopharmaceuticals Co., Ltd. is part of SK Group, South Korea's second-largest conglomerate. SK Group continues to grow in response to the rapidly changing global business environment, demonstrating leadership across key sectors such as semiconductors, energy, ICT and biotechnology. The group is strengthening its leadership position through strategic investments, technological innovation, and global collaboration. With assets of USD 299.1 billion and revenue of USD 171.6 billion in 2025, SK Group is listed in the Fortune Global 500 companies and has 579 subsidiaries and branches worldwide. As a key player in SK Group's biotechnology sector, SK Biopharmaceuticals plays a central role in advancing pharmaceutical innovation, leveraging its integrated capabilities spanning drug discovery, clinical development, regulatory approval, and commercialization to bring innovative treatments to patients worldwide. For more information about SK Biopharmaceuticals, visit www.skbp.com/eng.

XCOPRI^® and ONTOZRY^® are registered trademarks of SK Biopharmaceuticals Co., Ltd.

About XCOPRI^® (cenobamate tablets) CV
Cenobamate is an antiseizure medication (ASM) discovered and developed by SK Biopharmaceuticals and SK Life Science. While the precise mechanism by which cenobamate exerts its therapeutic effect is unknown, it is believed to reduce repetitive neuronal firing by inhibiting voltage-gated sodium currents. It is also a positive allosteric modulator of the γ-aminobutyric acid (GABAA) ion channel.

Cenobamate is approved in the United States for the treatment of partial-onset seizures in adults and is available under the brand name XCOPRI^® (cenobamate tablets) CV. Cenobamate can be combined with other ASMs or used alone. The recommended initial dosage of cenobamate is 12.5 mg once-daily, with titration every two weeks; it is available in six tablet strengths for once-daily dosing: 12.5 mg, 25 mg, 50 mg, 100 mg, 150 mg and 200 mg.

Cenobamate is also approved in the European Union and the United Kingdom, where it is marketed by Angelini Pharma under the brand name ONTOZRY^®. Its global presence continues to expand across Latin America, Asia, Middle East and North Africa, and other regions through strategic partnerships, with regulatory approvals in more than 45 countries or regions worldwide.

IMPORTANT SAFETY INFORMATION AND INDICATION FOR XCOPRI^® (cenobamate tablets) CV

DO NOT TAKE XCOPRI IF YOU:

• Are allergic to cenobamate or any of the other ingredients in XCOPRI.
• Have a genetic problem (called Familial Short QT syndrome) that affects the electrical system of the heart.

XCOPRI CAN CAUSE SERIOUS SIDE EFFECTS, INCLUDING:

Allergic reactions: XCOPRI can cause serious skin rash or other serious allergic reactions which may affect organs and other parts of your body like the liver or blood cells. You may or may not have a rash with these types of reactions. Call your healthcare provider right away and go to the nearest emergency room if you have any of the following: swelling of your face, eyes, lips, or tongue, trouble swallowing or breathing, a skin rash, hives, fever, swollen glands, or sore throat that does not go away or comes and goes, painful sores in the mouth or around your eyes, yellowing of your skin or eyes, unusual bruising or bleeding, severe fatigue or weakness, severe muscle pain, frequent infections, or infections that do not go away. Take XCOPRI exactly as your healthcare provider tells you to take it. It is very important to increase your dose of XCOPRI slowly, as instructed by your healthcare provider.

QT shortening: XCOPRI may cause problems with the electrical system of the heart (QT shortening). Call your healthcare provider if you have symptoms of QT shortening including fast heartbeat (heart palpitations) that last a long time or fainting.

Suicidal behavior and ideation: Antiepileptic drugs, including XCOPRI, may cause suicidal thoughts or actions in a very small number of people, about 1 in 500. Call your health care provider right away if you have any of the following symptoms, especially if they are new, worse, or worry you: thoughts about suicide or dying; attempting to commit suicide; new or worse depression, anxiety, or irritability; feeling agitated or restless; panic attacks; trouble sleeping (insomnia); acting aggressive; being angry or violent; acting on dangerous impulses; an extreme increase in activity and talking (mania); or other unusual changes in behavior or mood.

Liver problems: XCOPRI may cause liver problems. Your healthcare provider will do blood tests to check your liver before you start XCOPRI and while you take XCOPRI if needed. Tell your healthcare provider right away if you have any symptoms of liver problems, such as: yellowing of the skin and eyes (jaundice), nausea, vomiting, unusual darkening of the urine, or feeling tired or weak.

Nervous system problems: XCOPRI may cause problems that affect your nervous system. Symptoms of nervous system problems include: dizziness, trouble walking or with coordination, feeling sleepy and tired, trouble concentrating, remembering, and thinking clearly, and vision problems. Do not drive, operate heavy machinery, or do other dangerous activities until you know how XCOPRI affects you.

Do not drink alcohol or take other medicines that can make you sleepy or dizzy while taking XCOPRI without first talking to your healthcare provider.

DISCONTINUATION:

Do not stop taking XCOPRI without first talking to your healthcare provider. Stopping XCOPRI suddenly can cause serious problems. Stopping seizure medicine suddenly in a patient who has epilepsy can cause seizures that will not stop (status epilepticus). 

DRUG INTERACTIONS:

XCOPRI may affect the way other medicines work, and other medicines may affect how XCOPRI works. Do not start or stop other medicines without talking to your healthcare provider. Tell healthcare providers about all the medicines you take, including prescription and over-the-counter medicines, vitamins and herbal supplements.

PREGNANCY AND LACTATION:

XCOPRI may cause your birth control medicine to be less effective. Talk to your health care provider about the best birth control method to use.

Talk to your health care provider if you are pregnant or plan to become pregnant. It is not known if XCOPRI will harm your unborn baby. Tell your healthcare provider right away if you become pregnant while taking XCOPRI. You and your healthcare provider will decide if you should take XCOPRI while you are pregnant. If you become pregnant while taking XCOPRI, talk to your healthcare provider about registering with the North American Antiepileptic Drug (NAAED) Pregnancy Registry. The purpose of this registry is to collect information about the safety of antiepileptic medicine during pregnancy. You can enroll in this registry by calling 1-888-233-2334 or go to www.aedpregnancyregistry.org.

Talk to your health care provider if you are breastfeeding or plan to breastfeed. It is not known if XCOPRI passes into breastmilk. Talk to your healthcare provider about the best way to feed your baby while taking XCOPRI.

COMMON SIDE EFFECTS:

The most common side effects in patients taking XCOPRI include dizziness, sleepiness, headache, double vision, and feeling tired.

These are not all the possible side effects of XCOPRI. Tell your healthcare provider if you have any side effect that bothers you or that does not go away. For more information, ask your healthcare provider or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

DRUG ABUSE:

XCOPRI is a federally controlled substance (CV) because it can be abused or lead to dependence. Keep XCOPRI in a safe place to prevent misuse and abuse. Selling or giving away XCOPRI may harm others and is against the law.

INDICATION:

XCOPRI is a prescription medicine used to treat partial-onset seizures in adults 18 years of age and older. It is not known if XCOPRI is safe and effective in children under 18 years of age.

Please see additional patient information in the Medication Guide. This information does not take the place of talking with your healthcare provider about your condition or your treatment.

Please see full Prescribing Information.

SOURCE SK Life Science, Inc.