Merck KGaA faces probe in France over whether it misled patients about drug reformulation

Merck KGaA’s problems in France over its thyroid hormone replacement drug Levothyrox aren’t going away.

Seven months after France’s highest court confirmed an earlier ruling that the German company must compensate users who suffered problems from Levothyrox, the case has advanced at the judicial level.

On Tuesday, a judge in Marseille opened a formal indictment to determine if the company provided misleading information when it switched the formulation of Levothyrox, a medicine also known as Euthyrox.

In 2017, Merck KGaA reworked the drug by replacing lactose with mannitol and adding citric acid to improve potency and extend shelf life. After that switch, patient complaints prompted the French government to ask Merck KGaA to relaunch the old version, Science Magazine reported at the time.

Further, after some users developed adverse reactions, France launched a preliminary investigation, with police raiding the company’s offices in Lyon.

But both the company and French regulators have said the new formulation is bioequivalent to the previous one.

“The quality of the new formulation of Euthyrox has been confirmed on many different occasions by French, European and international health authorities,” Merck KGaA wrote in the Wednesday statement.

The criminal probe, which authorities launched in 2018, doesn’t concern Merck KGaA’s formulation of Levothyrox. Instead, it centers around what the company said about the switch.

“Merck has now full access to the file and will therefore be able to defend itself in full knowledge of the facts and to provide any clarification necessary to establish that no criminal offense of any kind was committed,” a company spokesperson said in an emailed statement.

The judge has placed company under court supervision, asking for a deposit of 4.3 million euros ($4.2 million) and to provide a banking guarantee of up to 7 million euros ($6.8 million). Merck KGaA’s lawyer Mario-Pierre Stasi told Reuters that the amounts were “totally unjustified.”

In March of this year, France’s Cour de Cassation confirmed an earlier ruling and ordered Merck to pay 1,000 euros ($982.30) each to compensate more than 3,300 Levothrox users who suffered thyroid problems.

The company stressed that Levothyrox has been approved and launched in more than 40 countries, with France the only one pursuing litigation. The drug is used by more than 18 million patients, most of them women. Merck KGaA also said it will continue to “introduce the new formulation in various countries according to schedule.”