CJEU Rules on Medical Devices with Reversible Molecular Interactions

The Court of Justice of the European Union (CJEU) ruled (C-589/23) on the classification of certain medical devices. The ruling affects products containing substances that exert molecular bindings, even if reversible.

The CJEU determined that substances preventing bacterial adhesion through reversible binding exert a Pharmacological Action. In accordance with Directive 2001/83 (the Directive), such products qualify as medicinal products. In accordance with Article 2(2) of the Directive, the classification as a medicinal product takes precedence on a classification as a medical device.

Manufacturers of similar products may need to market them as medicinal products if they exhibit reversible pharmacological actions. This would require obtaining a marketing authorization from a national competent authority, or, from the European Commission.

A. The Preliminary Question at hand

On 13 March 2025, the CJEU delivered a preliminary ruling concerning substances exerting a Pharmacological Action. The CJEU was called upon to interpret the term “pharmacological action”. The question answered was:

“Whether Article 1(2)(b) of Directive 2001/83 must be interpreted as meaning that a substance which, by means of a reversible binding to bacteria, prevents the bacteria from adhering to human cells must be regarded as exerting a ‘pharmacological action’ within the meaning of that provision.”

B. Underlying Facts that led to the Preliminary Question

Cassela-med GmbH & Co. KG (“Cassela-med”) marketed two products, “Femannose” and “Femannose N” as medical devices. The main constituants are D-mannose and cranberry extract (only for Femannose), intended for the prevention and treatment of certain urinary infections. Femannose was promoted by MCM Klosterfrau on its website until October 2017.

Verband Sozialer Wettbewerb eV (“VSW”), an association dedicated to protecting the commercial interests of its members, contested this classification. They argued that these products should be considered as medicinal products and not as medical devices. A regional court in Germany, followed VSW’s reasoning on 15 January 2020. On 23 December 2020, Cassela-med and MCM Klosterfrau appealed against this judgment, but it was dismissed. The appelate court held that D-mannose, an active ingredient in the products, exerted a pharmacological action by binding to bacteria and preventing their adhesion to human cells. Cassela-med and MCM Klosterfrau then took the case to the German Federal Court of Justice, which decided to refer a preliminary question to the CJEU.

C. Reasoning of the CJEU

The CJEU reiterated the definitions of medicinal products and medical devices. When a substance’s main effect is pharmacological, it cannot be classified as a medical device.

Further, the CJEU reasoned that the terms “pharmacological action” in the Directive and “action by pharmacological means” in the Medical Devices Directive refer to the same concept and should be interpreted uniformly.

The CJEU, then, concluded that the products in question fit the definition of a medicinal product:

• Pharmacological action occurs through molecular-level interactions that influence physiological or pathological processes.
• Interaction at the molecular level does not require modification of molecular structures.
• Even weak molecular bonds, like hydrogen bonding, qualify as pharmacological interactions.
• Pharmacological effects can occur even if the substance interacts with bacteria, viruses, or parasites instead of human cells.
• Preventing bacterial adhesion to human cells is considered a blockade of pathological processes.
• A pharmacological effect can still exist even if the molecular binding is reversible.

On this basis, the CJEU ruled that such substances may be classified as medicinal products.

In accordance with Article 2(2) of the Directive, the classification as a medicinal product takes precedence on a classification as a medical device. In other words, if a product fits both the definition of a medicinal product and that of a Medical Device (Medical Devices Directive and now Regulation), the product should be classified as a medicinal product.

In light of the above, the products in question will likely need to be marketed as medicinal products instead of medical devices if they want to remain on the market.

D. Implications of the Judgment

The ruling has an inter partes effect, meaning it is binding on the parties involved in the dispute submitted to the national court. In this context, it means that the German Federal Court of Justice must follow the CJEU's interpretation when making its final decision on the classification of the "Femannose" and "Femannose N" products.

As a result, these products will need to be re-classified as medicinal products to be marketed in the EU.

Further, the decision also has an erga omnes effect, implying that all other EU jurisdictions must respect the authority of the CJEU's interpretation. Other courts faced with similar borderline classifications, must apply the CJEU’s interpretation, which could lead to a reclassification of products producing similar effects.

As such, market surveillance authorities, may also be investigating related classifications of similar products.

_{This article was published with the assistance of Pauline Demanet.}