European health regulators are calling for stricter monitoring of patients taking cenobamate, an epilepsy medication, following reports of rare but severe liver injuries. The Pharmacovigilance Risk Assessment Committee (PRAC) of the European Medicines Agency (EMA) has recommended new safety measures to ensure the early detection of hepatic impairment, including cases of liver failure.
The drug, marketed as Ontozry in Europe, is specifically indicated for the treatment of focal-onset seizures—epileptic activity that begins in a limited area of the brain and may subsequently spread. It is typically used as an adjuvant therapy for adults whose seizures remain uncontrolled despite the prior use of at least two other antiepileptic medications.
As a physician and medical writer, I have seen how the introduction of new anticonvulsants can offer a lifeline to patients with refractory epilepsy. However, the balance between seizure control and systemic toxicity is delicate. The latest findings from the Pharmacovigilance Risk Assessment Committee (PRAC) highlight this tension, noting that while severe liver damage is rare, it is significant enough to warrant a change in clinical protocol.
The PRAC analysis revealed that most cases of severe liver injury occurred in patients who were using cenobamate in combination with other anticonvulsant treatments. This suggests a potential synergistic effect or a cumulative metabolic burden on the liver that clinicians must now account for during prescription and follow-up.
Understanding the liver safety measures for cenobamate
The primary objective of the new guidelines is the early identification of liver stress before it progresses to irreversible failure. To achieve this, the EMA is recommending that healthcare providers perform liver function tests (LFTs) both before the patient begins treatment and at regular intervals throughout the duration of the therapy.
It is important to distinguish between common laboratory fluctuations and severe clinical injury. For many patients, cenobamate causes a rise in liver enzymes—a frequent side effect occurring in approximately one in ten patients. While often asymptomatic and manageable, these elevations can be precursors to more serious issues.
The PRAC is now recommending that severe liver injuries be formally classified as a rare adverse reaction, with an estimated frequency of up to 1 in 1,000 patients. This distinction is critical for both doctors and patients to understand the actual statistical risk versus the severity of the potential outcome.
| Reaction Type | Estimated Frequency | Clinical Significance |
|---|---|---|
| Increased Liver Enzymes | Common (1 in 10) | Often monitored via blood tests; may not require cessation. |
| Severe Liver Injury/Failure | Rare (Up to 1 in 1,000) | Severe; requires immediate medical intervention and dose adjustment. |
Warning signs and patient management
Patients taking cenobamate are urged to be vigilant regarding their physical health. Due to the fact that liver failure can develop insidiously, recognizing the early warning signs is essential for a positive prognosis. The EMA identifies several key symptoms that require immediate medical evaluation:
- Unusual or persistent fatigue, and lethargy.
- A noticeable loss of appetite.
- Discomfort or pain in the upper right quadrant of the abdomen.
- Dark-colored urine.
- Jaundice, characterized by a yellowing of the skin or the whites of the eyes.
When liver injury is suspected or confirmed through laboratory analysis, physicians are advised to consider reducing the dosage or discontinuing the medication entirely. However, there is a critical clinical caveat: the medication should not be stopped abruptly unless absolutely necessary. Sudden cessation of antiepileptic drugs can trigger a rebound effect, significantly increasing the risk of severe seizures or status epilepticus.
The regulatory path forward
The recommendations issued by the PRAC are not the final step in the regulatory process. These findings will now be transmitted to the Committee for Medicinal Products for Human Use (CHMP), the EMA’s primary scientific committee. Once the CHMP adopts these recommendations, the marketing authorization holder will be required to distribute a direct communication to healthcare professionals.
This communication will be disseminated through a coordinated plan, ensuring that the updated warnings reach national registries across all European Union member states and are published on official European health platforms. This ensures that every neurologist and general practitioner prescribing the drug is aware of the updated monitoring requirements.
Disclaimer: This article is for informational purposes only and does not constitute medical advice. Patients should not change their medication or dosage without consulting their prescribing physician.
The next phase of this safety update depends on the formal adoption of these measures by the CHMP, which will trigger the official updating of the product’s Summary of Product Characteristics (SmPC) and patient information leaflets across the EU.
Do you or a loved one take cenobamate? We invite you to share your experiences with medication monitoring in the comments below or share this article with others in the epilepsy community.
