PRAC concludes evaluation of new data regarding potential risk of neurodevelopmental disorders in children born to men treated with valproate

PRAC Reviews Valproate NDD Risk, Maintains Precautionary Measures

The European Medicines Agency's (EMA) Pharmacovigilance Risk Assessment Committee (PRAC) has completed its review of new data concerning the potential risk of neurodevelopmental disorders (NDDs) in children born to men treated with valproate. The committee concluded that the evidence on NDDs is inconsistent and the causal role of valproate is uncertain. Consequently, PRAC recommended maintaining the existing precautionary measures for male patients, which were introduced in 2024 to address a potential increased risk of NDDs in children born to men treated with valproate during the three months before conception. The product information for valproate medicines will also be updated to reflect the most recent data. A larger, specifically designed study is currently ongoing and is expected to conclude in 2028.

• The PRAC's latest review of valproate safety data found inconsistent evidence regarding neurodevelopmental disorders (NDDs) in children born to men treated with the drug before conception. While a 2024 post-authorisation safety study (PASS) suggested an increased risk, a more recent Danish nationwide registry-based study published in 2025 did not. The committee noted that differences in study design, patient inclusion, and accounting for underlying health conditions might explain these varying findings, leading to uncertainty about a causal link between paternal valproate use and NDDs.
• Despite the inconsistent evidence, the PRAC recommended that precautionary measures for male patients, initially implemented in 2024, should remain in place. These measures were established to address a potential increased risk of NDDs in children born to men treated with valproate during the three months prior to conception. Furthermore, the committee advised updating the product information, healthcare professional guide, and male patient guide to ensure all stakeholders have access to the most current safety data and recommendations regarding valproate use.
• The PRAC's decision to maintain existing precautionary measures is partly due to remaining uncertainties, pending the results of a larger, specifically designed study. This study was requested by PRAC from marketing authorisation holders to address limitations identified in the earlier PASS study. It is currently ongoing and is anticipated to conclude in 2028, at which point further data will be available to potentially provide more definitive conclusions regarding the safety signal and the causal role of valproate in neurodevelopmental disorders.

PRAC's Latest Review of Valproate's Paternal NDD Risk

Recent safety data demonstrates that valproate carries significant tolerability concerns across multiple clinical populations, with the severity and frequency of adverse effects varying substantially by indication, patient age, and dosing regimen. Contemporary evidence from 2024 highlights acute hematological risks, particularly thrombocytopenia requiring treatment discontinuation, though platelet levels typically normalize within two weeks. Healthcare provider communication and intensive monitoring during the initial six months following initiation or dose escalation remain critical, as valproate exhibits clinically significant adverse effects that can be life-threatening.

The most frequently reported adverse effects involve gastrointestinal, neurological, and hematological systems, with common reactions including tremor, weight gain, gastrointestinal disturbances, liver dysfunction, metabolic acidosis, thrombocytopenia, and alopecia. Meta-analytic evidence from dementia studies reveals concerning safety signals, with valproate-treated participants experiencing significantly higher rates of adverse effects (OR 2.02, 95% CI 1.30 to 3.14) and serious adverse events (OR 4.77, 95% CI 1.00 to 22.74). Specific adverse events include sedation, gastrointestinal symptoms, and urinary tract infections, leading to recommendations against valproate use for agitation management in dementia populations due to increased risk in this vulnerable group.

Age-related tolerability patterns show distinct profiles across populations. Elderly patients demonstrate heightened susceptibility to adverse effects, particularly sedation, cognitive impairment, and osteoporosis, necessitating lower starting doses and gradual titration. Adult populations show moderate-quality evidence for increased adverse event rates compared to placebo (83% vs 75%, OR 1.63), with sedation occurring significantly more frequently than controls. Pediatric data reveals weight gain as a primary concern, with statistically significant increases in weight and BMI percentiles at 36 and 48 months of follow-up. Withdrawal from valproate therapy carries additional risks, with significantly increased hazard ratios for emergency department attendance (1.236), hospital admissions (1.160), falls (1.179), and new-onset depression (1.323), though overall mortality risk remains unchanged.

Navigating Treatment Challenges in Epilepsy and Bipolar Disorder

Current treatment approaches for epilepsy and bipolar disorder face significant obstacles that impact patient outcomes and quality of life. Despite advances in medication development, substantial gaps remain between treatment efficacy in clinical trials and real-world effectiveness. These challenges span from drug resistance and adherence issues to diagnostic complexities and individualized treatment selection.

• Drug resistance remains a major barrier, with approximately one-third of epilepsy patients remaining refractory to treatment despite over 20 available antiseizure medications, while bipolar disorder shows nonadherence rates reaching 90% with suboptimal outcomes despite 15+ approved treatments

• Limited treatment efficacy affects substantial patient populations, as only a subset of bipolar patients achieve full remission even with lithium (the most effective option), and around 30% of epilepsy patients cannot achieve seizure control with current antiepileptic drugs

• Medication tolerability significantly impacts treatment success, with many patients unable to tolerate long-term side effects of current therapies, and adverse medication effects potentially explaining more variance in quality of life than seizure frequency in pharmacoresistant epilepsy

• Treatment adherence poses persistent challenges, driven by factors including high per-capita income requirements, medication costs and availability, side effects, seizure frequency in epilepsy, and alcohol consumption, negative treatment attitudes, and early treatment initiation age in bipolar disorder

• Diagnostic accuracy remains problematic, particularly for bipolar disorder where early diagnosis is challenging, misdiagnoses are frequent, and bipolar depression is commonly misdiagnosed as unipolar depression since patients typically seek treatment during depressive rather than manic episodes

• Individualized treatment selection lacks precision, as predicting which medications will be most effective or tolerable for specific patients is not yet possible, and treatment choice often relies on physician subjective decisions, personal experience, and pharmaceutical marketing pressure rather than evidence-based biomarkers

• Complex treatment requirements increase management burden, with many patients requiring combination therapies, adjunctive psychotherapy, and individualized regimens that are difficult to implement in real-world clinical settings with insufficient consultation time to address patient concerns

Valproate's Role in Current Epilepsy and Bipolar Disorder SoC

Current epilepsy management guidelines emphasize a structured, patient-centered approach that begins with accurate seizure classification and risk stratification following initial seizures. Medical management centers on seizure control through anti-seizure medications (ASMs), with primary treatment goals focused on maximizing seizure control, reducing medication side effects, and improving quality of life. Critical considerations include ASM teratogenicity in women of childbearing age and the implementation of tailored treatment plans based on individual patient factors. Early referral to specialist teams is emphasized as essential for optimal diagnosis and management outcomes.

However, up to one-third of patients develop drug-resistant epilepsy, necessitating specialist interventions including epilepsy surgery or neuromodulation approaches. Complex scenarios require specialist multidisciplinary evaluation, and timely specialist input significantly enhances outcomes in patients with challenging or refractory epilepsy. Modern guidelines advocate for a holistic, personalized medicine approach that addresses both medical and psychosocial aspects of epilepsy, incorporating standardized pathways for emergency department evaluation and follow-up at specialized epilepsy units for newly diagnosed patients.

For bipolar disorder, current standard of care follows a multimodal, lifelong management approach supported by Canadian Network for Mood and Anxiety Treatments (CANMAT) and International Society for Bipolar Disorders (ISBD) guidelines. These guidelines provide evidence-based pharmacological and psychosocial interventions across all phases of illness, with lithium remaining a first-line pharmacological treatment, particularly in older-age bipolar disorder. Treatment frameworks emphasize embedding care within community settings including primary care, schools, digital platforms, and family systems to enable early risk identification, preventive strategy delivery, and sustained long-term maintenance. Despite these advances, implementation challenges persist, with diagnosis often delayed, pharmacotherapy inconsistently prescribed or monitored, psychosocial interventions underused, and relapse prevention strategies rarely sustained in real-world practice.

Valproate's Male-Mediated NDD Risk: Uncertainty Persists

The recent review by the European Medicines Agency's PRAC regarding valproate's potential male-mediated neurodevelopmental risks marks a critical juncture for this long-standing antiepileptic drug. While the committee concluded that current evidence on neurodevelopmental disorders (NDDs) in children born to men treated with valproate is inconsistent and the causal role uncertain, this decision does not fully alleviate concerns. It underscores a complex landscape where a drug with established efficacy also carries significant, albeit evolving, safety considerations.

For decades, valproate has been recognized for its efficacy in treating epilepsy and bipolar disorder. However, extensive research has consistently demonstrated a high risk of major congenital malformations and neurodevelopmental disorders, including autism spectrum disorder and intellectual disability, in children exposed in utero to maternal valproate. This has led to stringent restrictions on its use in women of childbearing potential, with guidelines strongly recommending alternatives like lamotrigine or levetiracetam where clinically feasible.

The current focus on male-mediated risks introduces a new dimension to valproate's safety profile. The PRAC's recommendation to maintain existing precautionary measures for male patients, while awaiting a larger, dedicated study due in 2028, highlights a period of prolonged uncertainty. This delay in definitive data means prescribers and patients will continue to navigate an environment where potential risks, even if unconfirmed, influence treatment decisions. The pharmaceutical industry must prepare for potential future regulatory shifts, which could further impact valproate's market position and necessitate enhanced risk communication strategies. This evolving understanding of valproate's broader reproductive safety profile reinforces the imperative for continuous pharmacovigilance and patient-centric counseling across all demographics.