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Sanofi reports issues around safety study into valproate

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Nicola Swanborough

Sanofi reports issues around safety study into valproate

New prescribing practices for valproate were introduced in December last year, after a safety study suggested there could be risk of harm for babies through paternal exposure up to three months before conception. Now the drug manufacturer says there are issues with the safety study and that further analysis is necessary.

It is important never to stop taking valproate – or any medication – without consulting your doctor.

Sanofi, the drug company which manufactures the epilepsy medication, sodium valproate, has warned of issues with a recent safety study into the potential risks of neurodevelopmental disorders in children whose fathers were taking the drug up to three months prior to conception.

The retrospective observational safety study was based on electronic medical records from three Nordic countries and was requested by the European Medicines Agency. It looked at the potential risk of harm in children whose fathers were treated with valproate in the three months before conception, compared with the risk in children whose fathers were treated with either lamotrigine or levetiracetam for the same period.

Following the review, new prescribing practices for valproate were introduced in the UK last December which meant that, for the first time, both men and women under the age of 55 who were prescribed the drug would have to have two signatures from specialists confirming that there was no suitable alternative medication.

Risks around paternal exposure to valproate

Data from the safety study has still not been shared with the UK’s epilepsy charities. However, a communication alert from the New Zealand Medicines and Medical Devices Authority, said that the elevated risk of neurodevelopmental disorders in babies from paternal exposure, ranged from 5.6-6.3% compared with 2.5-3.6% from paternal exposure to lamotrigine or levetiracetam.

Now Sanofi says the data has limitations and that further analysis is required before any conclusions can be drawn. In a statement on its website, it says: “A thorough data review process has shown that new analyses need to be performed before final conclusions can be drawn from the study. We have informed health authorities of this situation and are working diligently with them.”

Awaiting re-analysis

UK medicines regulator the MHRA said it was continuing to monitor the safety of valproate. A spokesperson said: “We continue to rigorously review all emerging scientific data. This includes a study on outcomes of children whose fathers took valproate at the time of conception, which the European Medicines Agency asked the Company to carry out. 

“Sanofi has recently informed us about issues with the data that require re-analysis before any final conclusions can be drawn from it, and we are ready to review this re-analysis as soon as it is available. 

“Healthcare professionals and patients are reminded about the importance of following the requirements of the Pregnancy Prevention Programme for women and the need for all patients to be informed of the reproductive risks of valproate, as outlined in the product information.

“Until then, our advice to patients remains that no one should stop taking valproate without advice from their healthcare professional.”

Our Medical Director responds

Professor Ley Sander, Medical Director at the Epilepsy Society, said that it was essential for anyone taking valproate to be fully aware of the potential risks both prior to conception and during pregnancy. But they should also be aware of the risks of seizures if they change to a different medication.

“Valproate remains one of the most effective seizure medications but we know that it carries high risks during pregnancy for a developing baby. It should only be prescribed to women if a Pregnancy Prevention Programme is in place," he said.

“We still do not have full details of the risks for babies born to fathers who were taking valproate in the three months prior to conception. It is important that all men under the age of 55 discuss their individual risks with their doctor and consider whether they can safely change to an alternative medication.

“I hope that as robust data emerges, the position will become clearer. The challenging decisions that people with epilepsy and healthcare professionals are having to make, underlines why more research into the risks around epilepsy medications and pregnancy is vital.

“We do not have a magic wand. We do not have a treatment that will work for everyone with minimal risks. But we do have scientific knowledge and expertise that must be allowed to conduct essential research into the safety of epilepsy medications both before and during pregnancy. We owe that to future parents and future generations. It is vital that the Government invests in this work now.”

You can read the response of the Epilepsy Coalition here.

Further information

Information about valproate and the Pregnancy Prevention Programme

Government guidance for valproate

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