XCOPRI® (cenobamate tablets) CV Efficacy

Results from a study of adult patients with a median of 9 seizures/28 days at baseline^1,2

Primary outcome: Patients experienced up to 2x greater seizure reduction with XCOPRI compared with placebo (55% XCOPRI 400 mg, 55% XCOPRI 200 mg, 36% XCOPRI 100 mg vs 24% placebo)

Secondary outcome: As many as 1 in 5 patients experienced zero seizures with XCOPRI during the maintenance phase (21% XCOPRI 400 mg, 11% XCOPRI 200 mg, 4% XCOPRI 100 mg, 1% placebo)

Zero seizure rates achieved within 4 weeks and increased over time⁶

Results from a post hoc analysis of a phase 3 study: Percentage of patients with 1-2 seizures/28 days
at baseline who achieved zero seizures within the first 4 weeks taking XCOPRI

Limitations: This post hoc analysis of an open-label phase 3 study of XCOPRI did not include a control arm. These data are descriptive and representative of an enriched population with a relatively small number of patients. Appropriate multiplicity adjustments were not applied.

XCOPRI was assessed in a multicenter, open-label safety study in patients 18 to 70 years old with uncontrolled focal seizures despite taking a stable dosage of 1 to 3 anti-seizure medications. The study included a screening period of up to 21 days followed by an open-label treatment period consisting of a 12-week titration phase, followed by an open-label maintenance phase. The maintenance phase continued for the length of the study (total study duration was up to 43 months). Patients initiated XCOPRI treatment using the FDA-approved titration schedule. After reaching 200 mg/day, further increases up to 400 mg/day using biweekly increments of 50 mg/day were allowed during the maintenance phase. Reductions below 200 mg were allowed at investigators’ clinical judgment (minimum allowed dosage was 50 mg/day). XCOPRI monotherapy was not allowed. Patient visits occurred every 2 weeks for 16 weeks and then every 1 to 3 months.

A post hoc analysis in a subset of patients (n=240) evaluated the impact of baseline seizure frequency (<3 seizures/28 days vs ≥3 seizures/28 days) on mean XCOPRI dosage required to achieve 100% seizure reduction, duration of this response, and responder rates. To be eligible for the post hoc analysis, the following criteria must have been met: patients must have had at least 1 focal aware motor, focal impaired awareness, or focal to bilateral tonic-clonic seizure per 13 weeks baseline prior to screening visit; seizure data while on treatment; and consistent documentation of good-quality, raw seizure data for ≥85% of the time spent in the study. Responder rates (≥50%, ≥75%, ≥90%, and 100%) were assessed during the entire treatment period (ie, including during the titration and maintenance phases).

“XCOPRI is not just for your hard-to-treat patients. XCOPRI may help many of your patients, even those experiencing few seizures or those who were recently diagnosed.”

– David Vossler, MD, FAAN, FAES, FACNS

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*Worldwide new-to-brand cenobamate prescriptions as of December 2025. Source: IQVIA.

References: 1. Krauss GL, Klein P, Brandt C, et al. Safety and efficacy of adjunctive cenobamate (YKP3089) in patients with uncontrolled focal seizures: a multicentre, double-blind, randomised, placebo-controlled, dose-response trial. Lancet Neurol. 2020;19(1):38-48. 2. XCOPRI [package insert]. Paramus, NJ: SK Life Science, Inc. 3. Krauss GL, Klein P, Brandt C, et al. Safety and efficacy of adjunctive cenobamate (YKP3089) in patients with uncontrolled focal seizures: a multicentre, double-blind, randomised, placebo-controlled, dose-response trial. Lancet Neurol. 2020;19(1)(suppl 1):S1-S7. 4. Fisher RS, Cross JH, French JA, et al. Operational classification of seizure types by the International League Against Epilepsy: position paper of the ILAE Commission for Classification and Terminology. Epilepsia. 2017;58(4):522-530. 5. Chung SS, French JA, Kowalski J, et al. Randomized phase 2 study of adjunctive cenobamate in patients with uncontrolled focal seizures. Neurology. 2020;94(22):e2311-e2322. 6. Aboumatar S, Biton V, Wechsler R, Ferrari L, Rosenfeld WE. Post hoc analysis of a phase 3 study for treatment of uncontrolled focal seizures: adjunctive cenobamate dose and seizure reduction by baseline seizure frequency. Epilepsy Res. 2022;186:107014. 7. Data on file. SK Life Science, Inc. 8. Rosenfeld WE, Abou-Khalil B, Aboumatar S, et al. Post hoc analysis of a phase 3, multicenter, open-label study of cenobamate for treatment of uncontrolled focal seizures: effects of dose adjustments of concomitant antiseizure medications. Epilepsia. 2021;62(12):3016-3028.

INDICATION

XCOPRI is indicated for the
treatment of partial-onset
seizures in adult patients.

Important Safety Information
and indication

CONTRAINDICATIONS
XCOPRI is contraindicated in patients with hypersensitivity to cenobamate or any of the ingredients in the product.
XCOPRI is contraindicated in patients with Familial Short QT syndrome.

IMPORTANT SAFETY INFORMATION and INDICATION for XCOPRI^® (cenobamate tablets) CV

CONTRAINDICATIONS

XCOPRI is contraindicated in patients with hypersensitivity to cenobamate or any of the ingredients in the product.

XCOPRI is contraindicated in patients with Familial Short QT syndrome.

WARNINGS AND PRECAUTIONS

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS): Also known as Multiorgan hypersensitivity, has been reported in patients taking antiepileptic drugs, including XCOPRI. DRESS has been reported, including one fatality, when XCOPRI is titrated rapidly (weekly or faster titration). No cases of DRESS were reported in an open-label safety study of 1339 partial-onset seizure patients when XCOPRI was initiated at 12.5 mg/day and titrated every two weeks. This finding does not establish that the risk of DRESS is prevented by a slower titration; however, XCOPRI should be initiated at 12.5 mg once daily and titrated every two weeks. DRESS typically, although not exclusively, presents with fever, rash, and/or lymphadenopathy, in association with other organ system involvement. Eosinophilia is often present. If such signs or symptoms are present, the patient should be evaluated immediately. XCOPRI should be discontinued immediately and not restarted if an alternative etiology for the signs or symptoms cannot be established.

QT Shortening: XCOPRI can cause shortening of the QT interval. Caution should be used when administering XCOPRI and other drugs that shorten the QT interval as there may be a synergistic effect on the QT interval that would increase the QT shortening risk.

Suicidal Behavior and Ideation: Antiepileptic drugs (AEDs), including XCOPRI, increase the risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Patients treated with any AED for any indication should be monitored for the emergence or worsening of depression, suicidal thoughts or behavior, and/or any unusual changes in mood or behavior. Advise patients, their caregivers, and/or families to be alert for these behavioral changes and report them immediately to a healthcare provider.

Liver Injury: Clinically significant liver injury has occurred in patients taking XCOPRI. Obtain serum transaminases (ALT and AST) and total bilirubin, if not recently available (i.e., within 3 months) before initiating XCOPRI, and during treatment if clinically indicated. Monitor patients for signs and symptoms of any hepatic injury during treatment. Discontinue XCOPRI in patients with evidence of liver injury in the absence of an alternative etiology.

Neurological Adverse Reactions: XCOPRI can cause dose-dependent increases in the neurologic adverse reactions including dizziness, diplopia, disturbance in gait and coordination, somnolence, and fatigue.

Prescribers should advise patients against engaging in hazardous activities requiring mental alertness, such as operating motor vehicles or dangerous machinery, until the effect of XCOPRI is known.

Withdrawal of AEDs: As with all antiepileptic drugs, XCOPRI should generally be withdrawn gradually because of the risk of increased seizure frequency and status epilepticus. If withdrawal is needed because of a serious adverse event, rapid discontinuation can be considered.

MOST COMMON ADVERSE REACTIONS

In adult adjunctive therapy placebo-controlled clinical studies, the most common adverse reactions that occurred in XCOPRI-treated patients (incidence at least 10% and greater than placebo) were somnolence, dizziness, fatigue, diplopia, headache.

DOSING CONSIDERATIONS

Dosage adjustment of XCOPRI or other concomitant medications may be necessary.

Consider gradually reducing phenytoin dosages by up to 50% during initial titration.
Consider reducing dosages of phenobarbital and clobazam as needed when used concomitantly with XCOPRI.
When XCOPRI and carbamazepine or lamotrigine are taken concomitantly, consider increasing dosages as needed of carbamazepine or lamotrigine.
Consider increasing dosages as needed of drugs which are CYP2B6 and CYP3A substrates and decreasing dosages as needed of drugs which are CYP2C19 substrates.
Effectiveness of hormonal oral contraceptives may be reduced when administered concomitantly with XCOPRI. Women should use additional or alternative non-hormonal birth control.

Dosage reduction of XCOPRI may be considered in patients with mild to moderate and severe renal impairment. XCOPRI is not recommended in end-stage renal disease.

The maximum recommended daily dose is 200 mg for patients with mild or moderate hepatic impairment. XCOPRI is not recommended in patients with severe hepatic impairment.

DRUG ABUSE

XCOPRI is a Schedule V controlled substance.

INDICATION

XCOPRI is indicated for the treatment of partial-onset seizures in adult patients.

Please see full Prescribing Information.

INDICATION

Important Safety Information and indication

Important Safety Information
and indication