Benfluorex, sold under the brand name Mediator, is an

anorectic An anorectic or anorexic is a drug which reduces appetite, resulting in lower food consumption, leading to weight loss. By contrast, an appetite stimulant is referred to as orexigenic. The term is (from the Greek ''ἀν-'' (an-) = "without" a ...

and

hypolipidemic agent Lipid-lowering agents, also sometimes referred to as hypolipidemic agents, cholesterol-lowering drugs, or antihyperlipidemic agents are a diverse group of pharmaceuticals that are used to lower the level of lipids and lipoproteins such as cholestero ...

that is structurally related to

fenfluramine Fenfluramine, sold under the brand name Fintepla, is a serotonergic medication used for the treatment of seizures associated with Dravet syndrome and Lennox–Gastaut syndrome.https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/212102s003lb ...

substituted amphetamine Substituted amphetamines are a class of compounds based upon the amphetamine structure; it includes all derivative compounds which are formed by replacing, or substituting, one or more hydrogen atoms in the amphetamine core structure with sub ...

). It may improve

glycemic control The term ''diabetes'' includes several different metabolic disorders that all, if left untreated, result in abnormally high concentration of a sugar called glucose in the blood. Diabetes mellitus type 1 results when the pancreas no longer produces ...

and decrease

insulin resistance Insulin resistance (IR) is a pathological condition in which cell (biology), cells fail to respond normally to the hormone insulin. Insulin is a hormone that facilitates the transport of glucose from blood into cells, thereby reducing blood gluco ...

in people with poorly controlled

type-2 diabetes Type 2 diabetes, formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent urinatio ...

. It was on the market between 1976 and 2009, and is thought to have caused between 500 and 2,000 deaths. It was patented and manufactured by the French pharmaceutical company

Servier Servier Laboratories (French: Laboratoires Servier, often abbreviated to Servier) is an international pharmaceutical company governed by a non-profit foundation, with its headquarters in France (Suresnes). The consolidated turnover for the 2018 ...

. However, Servier is suspected of having marketed benfluorex at odds with the drug's medical properties. On March 29, 2021, a French court fined Servier €2.7m (£2.3m) after finding it guilty of deception and manslaughter.

Drug withdrawn

On 18 December 2009, the

European Medicines Agency The European Medicines Agency (EMA) is an agency of the European Union (EU) in charge of the evaluation and supervision of medicinal products. Prior to 2004, it was known as the European Agency for the Evaluation of Medicinal Products or Euro ...

recommended the withdrawal of all medicines containing benfluorex in the

European Union The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been des ...

, because their risks, particularly the risk of

heart valve disease Valvular heart disease is any cardiovascular disease process involving one or more of the four valves of the heart (the aortic and mitral valves on the left side of heart and the pulmonic and tricuspid valves on the right side of heart). These ...

(fenfluramine-like cardiovascular side effects), are greater than their benefits. Thus Frachon ''et al.'' showed a higher rate of unexplained valvular heart disease in people taking benfluorex. Weill ''et al.'' looked at over 1 million people with diabetes demonstrating a higher hospitalization rate in benfluorex takers for valvular heart disease. In France, the medication had been marketed by Servier as an adjuvant

antidiabetic Drugs used in diabetes treat diabetes mellitus by altering the glucose level in the blood. With the exceptions of insulin, most GLP receptor agonists (liraglutide, exenatide, and others), and pramlintide, all are administered orally and are thus ...

under the name Mediator. The drug was on the market between 1976 and 2009, and is thought to have caused between 500 and 2,000 deaths. The drug was also used in Spain, Portugal, and Cyprus. On March 29, 2021, a French court fined Servier €2.7m (£2.3m) after finding it guilty of deception and manslaughter, with Mediator linked to the deaths of up to 2,000 people. The former executive Jean-Philippe Seta was sentenced to a suspended jail sentence of four years. The French medicines agency, accused of failing to act quickly enough on warnings about the drug, was fined €303,000. The pharmaceutical group was acquitted of charges of fraud. Fenfluramine, a related drug, had been withdrawn from the market in 1997 after reports of

heart valve A heart valve is a one-way valve that allows blood to flow in one direction through the chambers of the heart. Four valves are usually present in a mammalian heart and together they determine the pathway of blood flow through the heart. A heart v ...

disease, pulmonary hypertension, and development of

cardiac fibrosis Cardiac fibrosis commonly refers to the excess deposition of extracellular matrix in the cardiac muscle, but the term may also refer to an abnormal thickening of the heart valves due to inappropriate proliferation of cardiac fibroblasts. Fibrotic c ...

. This side effect is mediated by the metabolite

norfenfluramine Norfenfluramine, or 3-trifluoromethylamphetamine, is a never-marketed drug of the amphetamine family that behaves as a serotonin and norepinephrine releasing agent and potent 5-HT2A, 5-HT2B, and 5-HT2C agonist. The action of norfenfluramine on ...

on 5HT_2B receptors of heart valves, leading to a characteristic pattern of heart failure following proliferation of cardiac fibroblasts on the

tricuspid valve The tricuspid valve, or right atrioventricular valve, is on the right dorsal side of the mammalian heart, at the superior portion of the right ventricle. The function of the valve is to allow blood to flow from the right atrium to the right vent ...

. Both fenfluramine and benfluorex form norfenfluramine as a metabolite. This side effect led to the withdrawal of fenfluramine as an anorectic drug worldwide, and later to the withdrawal of benfluorex in Europe.

References

{{Phenethylamines 5-HT2B agonists Antiobesity drugs Anorectics Hypolipidemic agents Benzoate esters Substituted amphetamines Trifluoromethyl compounds Monoamine releasing agents Serotonin receptor agonists World Anti-Doping Agency prohibited substances Withdrawn drugs