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By Matthias Blamont
PARIS, April 20 Up to 4,100 children in France
suffered major malformations in the womb after their mothers
took a treatment against epilepsy and bipolar disorders known as
valproate between 1967 and 2016, France's drug regulator said.
Valproate, which has been manufactured in France by Sanofi
under the brand Depakine for epilepsy and Depakote and
Depamide for bipolar disorders, is also believed to cause slow
neurological development, ANSM said on Thursday.
Sanofi said it had been transparent with the authorities and
that it had sought to keep doctors and patients abreast of
Parents of those affected, however, say the French state and
Sanofi were too slow to warn of the side effects, after the
risks to foetuses became clear by the early 1980s.
The French drug authority said it would also publish a study
on neurological effects of valproate in the second half of 2017.
Valproate was approved as an anti-epileptic drug in France
in 1967 and has become one of the most widely prescribed
treatments worldwide given its effectiveness on adult patients.
"We are aware of the painful situations faced by families
whose children have problems that may be related to their
mother’s treatment of anti-epileptic drugs during pregnancy," a
spokesman for Sanofi said in an emailed statement.
The U.S. Food and Drug Administration warned in 2013 that
valproate should not be taken during pregnancy and a Paris
prosecutor launched a preliminary investigation into the
authorisation and marketing of the drug in 2015 after a group of
families lodged a legal complaint.
Depakine, which lost its patent in 1998, is also prescribed
in more than 100 other countries.
(Editing by Sarah White/Richard Balmforth/Alexander Smith)