Summary;Judgment — ECLI:EU:C:2025:173
Date: 2025-03-13
Language of the case: German
Court formation: Fifth Chamber
Subject matter: Approximation of laws
Procedure: Reference for a preliminary ruling
Origin: Germany

Translation C-589/23 – 1 
Case C-589/23 
Request for a preliminary ruling 
Date lodged: 
25 September 2023 
Referring court: 
Bundesgerichtshof (Germany) 
Date of the decision to refer: 
14 September 2023 
Defendants and appellants in the appeal on a point of law: 
Cassella-med GmbH & Co.KG 
MCM Klosterfrau Vertriebsgesellschaft mbH 
Applicant and respondent in the appeal on a point of law: 
Verband Sozialer Wettbewerb e. V. 
      
BUNDESGERICHTSHOF (FEDERAL COURT OF JUSTICE, GERMANY) 
ORDER 
[…] 
In the case of 
1. Cassella-med GmbH & Co. KG, […] Cologne, 
2. MCM Klosterfrau Vertriebsgesellschaft mbH, […] Cologne, 
Defendants and appellants in the appeal on a point of law, 
[…] 
v 
Verband Sozialer Wettbewerb e. V., […] Berlin, 
EN 
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Applicant and respondent in the appeal on a point of law, 
[…] 
On 14 September 2023 […], the First Civil Chamber of the Federal Court of 
Justice 
made the following order: 
I. The proceedings are stayed. 
II. The following question on the interpretation of the first case in 
Article 1(2)(b) of Directive 2001/83/EC of the European Parliament 
and of the Council of 6 November 2001 on the Community code 
relating to medicinal products for human use (OJ 2001 L 311, p. 67) is 
referred to the Court of Justice of the European Union for a 
preliminary ruling: 
Is there a pharmacological action within the meaning of the first case 
in Article 1(2)(b) of Directive 2001/83/EC where the substance in 
question (in this case: D-mannose), by means of a reversible binding to 
bacteria via hydrogen bonds, prevents the bacteria from adhering to 
human cells (in this case: the bladder wall)? 
Grounds: 
1 A. The applicant is a registered association whose statutory duties include 
protecting the commercial interests of its members. Many of its members 
distribute medicinal products and medical devices. 
2 The first defendant distributed the product ‘Femannose®’ as a medical device ‘for 
the treatment and prevention of cystitis (bladder infection) and other urinary tract 
infections’. The product contained D-mannose and cranberry extract as essential 
ingredients. The second defendant operates a website on which the product was 
advertised until mid-October 2017. Since October 2017, the first defendant has 
marketed the product without the cranberry extract as an ingredient under the 
name ‘Femannose® N’. The packaging now states ‘for the prevention and to 
support the treatment of cystitis (bladder infection) and other urinary tract 
infections’. The applicant considers that the products cannot be marketed as 
medical devices; rather, they are medicinal products – and are indisputably not 
authorised as such. Following an unsuccessful letter of formal notice, the 
applicant requested that the first defendant be ordered, on pain of punitive 
administrative measures to compel specific conduct, to refrain from marketing 
and/or placing on the market, in the course of trade, the product ‘Femannose’ as a 
medical device, and to refrain from marketing and/or placing on the market and/or 
advertising as shown in the submitted advertisement, in the course of trade, the 
product ‘Femannose N’ as a medical device, and that the second defendant be 
ordered, on pain of administrative measures to compel specific conduct, to refrain 
CASSELLA-MED AND MCM KLOSTERFRAU 
 
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from advertising, in the course of trade, the product ‘Femannose’, in so far as is 
evident from the internet advertising submitted. It also requested the payment of a 
lump sum by way of reimbursement of the costs associated with the letter of 
formal notice plus interest. 
3 The Landgericht (Regional Court) upheld the action (LG Cologne, judgment of 
15 January 2020 – 84 0 224/17, juris). The appeal court dismissed the defendants’ 
appeal (Oberlandesgericht (Higher Regional Court; ‘OLG’) Cologne, PharmR 
2021, 144). By their appeal on a point of law, for which this Chamber has granted 
leave and which the applicant claims should be dismissed, the defendants are 
pursuing their application to have the action dismissed. 
4 The Chamber stayed the proceedings following two requests for a preliminary 
ruling from the Federal Administrative Court to the Court of Justice of the 
European Union (Federal Administrative Court (‘BVerwG’), ZMGR 2021, 380 
and PharmR 2021, 593). Since then, the Court of Justice of the European Union 
has ruled on the requests for a preliminary ruling (judgment of the Court of Justice 
of 19 January 2023, C-495/21 and C-496/21, PharmR 2023, 160 – Bundesrepublik 
Deutschland (Nasal drops)). 
5 B. The success of the appeal on a point of law depends on the interpretation of 
the first case in Article 1(2)(b) of Directive 2001/83/EC of 6 November 2001 on 
the Community code relating to medicinal products for human use. Before a 
ruling can be given on the appeal on a point of law, the proceedings must 
therefore be stayed and a preliminary ruling obtained from the Court of Justice of 
the European Union pursuant to point (b) of the first paragraph and the third 
paragraph of Article 267 TFEU. 
6 I. The appeal court held in essence that the applicant is entitled to claim 
injunctive relief under competition law because the first defendant has infringed 
Paragraph 3a of the Heilmittelwerbegesetz (Law on the advertising of medicinal 
products, ‘the HWG’) and the second defendant has infringed Paragraph 21 of the 
Arzneimittelgesetz (Law on medicinal products, ‘the AMG’). According to that 
court, the products at issue are medicinal products by function which cannot be 
placed on the market without authorisation. The products have a pharmacological 
action as there is an interaction between their main active ingredient (D-mannose) 
and a cellular constituent. The products also appreciably restore, correct or modify 
physiological functions in human beings. The required overall assessment, taking 
into account the other characteristics of the product, also leads to the conclusion 
that the products must be regarded as medicinal products by function. 
7 II. The appeal court rightly recognised the applicant’s standing to bring 
proceedings under Paragraph 8(3)(3) of the Gesetz gegen den unlauteren 
Wettbewerb (Law against unfair competition, ‘the UWG’) in the version 
applicable until 30 November 2021 (see Paragraph 15a(1) of the UWG). The 
prohibition of the advertising of medicinal products which require authorisation 
and which are not authorised or deemed to be authorised under the law on 
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medicinal products laid down in the first sentence of Paragraph 3a of the HWG 
and the prohibition of the placing on the market of finished medicinal products 
which have not been approved by the competent Federal authorities or for which 
the European Community or the European Union has not granted a marketing 
authorisation, laid down in the first sentence of Paragraph 21(1) of the AMG are – 
as the appeal court rightly determined – rules designed to regulate market 
behaviour within the meaning of Paragraph 3a of the UWG, the infringement of 
which has a noticeable adverse effect on the interests of the market participants 
concerned (see Federal Court of Justice (‘BGH’), judgment of 25 June 2015 – I 
ZR 11/14, PharmR 2016, 82 (paragraph 9) – Chlorhexidine, with further 
references). In so far as the appeal court correctly held that there was an 
infringement of the first sentence of Paragraph 3a of the HWG and the first 
sentence of Paragraph 21(1) of the AMG, there is a commercial practice which is 
unfair under Paragraph 3a of the UWG and inadmissible under Paragraph 3(1) of 
the UWG, which justifies an order to cease and desist being obtained (first 
sentence of Paragraph 8(1) of the UWG) due to the risk of recurrence in the 
present case. 
8 III. The success of the appeal on a point of law depends on whether the appeal 
court was right to find an infringement of the first sentence of Paragraph 3a of the 
HWG and the first sentence of Paragraph 21(1) of the AMG, since the first 
defendant’s products have a pharmacological action which is capable of 
modifying physiological functions in human beings significantly and are therefore 
medicinal products by function in accordance with Paragraph 2(1)(2)(a) of the 
AMG and Article 1(2)(b) of Directive 2001/83/EC. 
9 1. According to Paragraph 2(1)(2)(a) of the AMG, medicinal products are, inter 
alia, substances or preparations made from substances which may be used in or on 
the human body or can be administered to human beings with a view to restoring, 
correcting or modifying physiological functions by exerting a pharmacological, 
immunological or metabolic action. That provision is intended to transpose the 
first case in Article 1(2)(b) of Directive 2001/83/EC and must therefore be 
interpreted in accordance with EU law (BGH, judgment of 8 January 2015 – I ZR 
141/13, GRUR 2015, 811 paragraph 9) = WRP 2015, 969 – Mouthwash solution 
II). According to the first case in Article 1(2)(b) of Directive 2001/83/EC, 
medicinal products are any substance or combination of substances which may be 
used in or administered to human beings either with a view to restoring, correcting 
or modifying physiological functions by exerting a pharmacological, 
immunological or metabolic action. Under Article 2(2) of Directive 2001/83/EC 
(transposed by Paragraph 2(3a) of the AMG), that directive is to apply in cases of 
doubt, where, taking into account all its characteristics, a product may fall within 
the definition of a ‘medicinal product’ and within the definition of a product 
covered by other Community legislation. 
10 2. In accordance with the principles set out in the case-law of the Court of 
Justice of the European Union and the Chamber, the concept of medicinal product 
is to be broadly construed. This also applies to medicinal products by function in 
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accordance with Article 1(2)(b) of Directive 2001/83/EC (see judgment of the 
Court of Justice of 20 September 2007, C-84/06, [2007] ECR I-7609 
(paragraph 31) – Antroposana; BGH, order of 18 October 2012 – I ZR 38/12, 
GRUR-RR2013, 272 (paragraph 7) with further references). The existence of a 
medicinal product by function must be set out and, in the event of a challenge, 
proved by the person who invokes it (see BGH, judgment of 25 June 2015 – I ZR 
205/13, GRUR 2016, 302 (paragraph 13) = WRP 2016, 191 – Mouthwash 
solution III, with further references). It is for the courts of the Member States to 
determine whether the product in question constitutes a medicinal product by 
function (see judgment of the Court of Justice of 6 September 2012, C-308/11, 
GRUR 2012, 1167 (paragraph 35) = WRP 2013, 175 – Chemische Fabrik 
Kreussler; BGH, GRUR-RR 2013, 272 (paragraph 7)). In the absence of scientific 
evidence of a pharmacological, immunological or metabolic action, it cannot be 
assumed that the product is a medicinal product by function (see Court of Justice, 
GRUR 2012, 1167 (paragraph 30) – Chemische Fabrik Kreussler, with further 
references; PharmR 2023, 160 paragraph 44 – Bundesrepublik Deutschland 
(Nasal drops)). 
11 Useful information in order to clarify what is meant by ‘pharmacological … 
action’ within the meaning of Article 1(2)(b) of Directive 2001/83/EC may be 
taken from the guidelines on the delimitation of medicinal products and medical 
devices, compiled by an expert group of representatives of authorities and industry 
under the auspices of the European Commission under Council Directive 
93/42/EEC of 14 June 1993 concerning medical devices (‘Medical Devices: 
Guidance document – Borderline products, drug-delivery products and medical 
devices incorporating, as integral part, an ancillary medicinal substance or an 
ancillary human blood derivative’, MEDDEV 2.1/3 rev. 3, ‘the MEDDEV 
Guidelines’) (see BGH, judgment of 24 June 2010-1 ZR 166/08, GRUR 2010, 
1026 (paragraph 17) = WRP 2010, 1393 – Photodynamic therapy; judgment of 
24 November 2010 -IZR 204/09, PharmR 2011, 299 (paragraph 14) with further 
references; with regard to the Guidance Document on the demarcation between 
the Cosmetic Products Directive 76/768/EEC and the Medicinal Products 
Directive 2001/83/EC, see Court of Justice, GRUR 2012, 1167 (paragraphs 21 to 
27) – Chemische Fabrik Kreussler; BGH, PharmR 2016, 82 (paragraph 11) – 
Chlorhexidine, with further references), which, however, are not legally binding 
as such (see Court of Justice, GRUR 2012, 1167 (paragraph 23) – Chemische 
Fabrik Kreussler). Those guidelines, which have since been replaced by the 
‘Guidance on borderline between medical devices and medicinal products under 
Regulation (EU) 2017/745 on medical devices’ (MDCG 2022-5), state: 
‘Pharmacological means’ is understood as an interaction between the 
molecules of the substance in question and a cellular constituent, usually 
referred to as a receptor, which either results in a direct response, or which 
blocks the response to another agent. Although not a completely reliable 
criterion, the presence of a dose-response correlation is indicative of a 
pharmacological effect. 
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12 3. The appeal court proceeded from the principles set out and held that the 
products at issue have a pharmacological action. 
13 In its reasoning, the appeal court referred to the findings of the expert appointed 
by the court and stated that the main active ingredient of the products is D-
mannose, a monosaccharide of high importance for human metabolism, especially 
in the glycosylation of molecules. These use bacteria to attach to human mucous 
membranes or other surfaces. The bacteria use adhesins for this purpose. In the 
case of Escherichia coli bacteria, the adhesin FimH is located at the tip of the 
fimbriae. The fimbriae use FimH to attach themselves to the bladder wall and 
prevent the bacteria from being flushed out by the flow of urine. In addition, after 
the bacteria have attached to the surface of the bladder mucosa, FimH also triggers 
the biochemical process. The transcription of various genes and various 
biochemical processes takes place in the host cell, ultimately leading to a kind of 
rupture of the cell membrane and the inclusion of the bacterium in the human cell. 
14 The main effect of D-mannose is to bind to FimH in urine and thus to block the 
FimH and structures containing mannose from adhering to the bladder wall. By 
blocking further interaction between the bacterial FimH and the body’s own cells, 
the physiological processes of the bacterium and the pathophysiological processes 
of the urinary tract infection are undermined. A change in the transcription of 
various genes is observed in the bacterium in response to the binding of the FimH 
to structures containing mannose. This can best be interpreted in accordance with 
the definition in the MEDDEV Guidelines as meaning that the D-mannose on 
FimH adhesins has the effect of blocking the response to another agent. D-
mannose causes the physiological processes of the bacteria, which accompany 
adhesion to human cells, to be blocked by binding specifically to the cell 
structures of those bacteria. By blocking the adhesion of the FimH on the 
bacterium to mannosylated structures on the bladder wall, there is no biochemical 
reaction between the bacterium and the host cell. There is an interaction between 
D-mannose molecules and a cellular constituent. The bacteria cell clearly reacts 
by biochemical processes to the binding of FimH and the surface structures 
containing D-mannose. Whether the binding of D-mannose to the bacterium is 
reversible is irrelevant. 
15 4. By taking the position that the effect of the D-mannose on FimH adhesins is to 
block the response to another agent, in accordance with the MEDDEV Guidelines, 
the appeal court considered that the second alternative of the definition of 
‘pharmacological action’ given therein was satisfied, which requires an interaction 
between the molecules of the substance in question and a cellular constituent, 
usually referred to as a receptor, which blocks the response to another agent. It 
must be established whether, in so doing, the appeal court based its decision on a 
correct understanding of the concept of pharmacological action. 
16 a) The view taken in the appeal on a point of law is that, contrary to the opinion of 
the appeal court, the active substance D-mannose does not interact with a cellular 
constituent. Interaction would require a substance-induced irreversible interaction 
CASSELLA-MED AND MCM KLOSTERFRAU 
 
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between the substance and a cellular constituent due to prior binding. By contrast, 
binding which is physically reversible establishes only an interdependence, which 
does not constitute a sufficient characteristic of the required chemical-
pharmacological interaction. It has not been established whether and which 
processes are triggered between D-mannose and the bacterium. The substance 
does not interact with a harmful messenger or with a human target cell in a 
relevant way, but merely causes the harmful messenger to be flushed out of the 
body unchanged. The (reversible) binding to a bacterium alone cannot be equated 
to an adhesion to a human target cell. 
17 aa) As a preliminary point, the appeal on a point of law wrongly claims that it 
has not been established whether – and if so, which – processes are triggered 
between D-mannose and the bacterium. 
18 (1) The appeal court stated that the bacterial cell reacts by biochemical 
processes to the binding of FimH to the surface structures containing D-mannose; 
the physiological processes of the bacterium and the pathophysiological processes 
of the urinary tract infection are undermined, and a change in the transcription of 
various genes is observed in the bacterium in response to the binding of the FimH 
to structures containing mannose. In so doing, the appeal court explained in detail, 
in the exercise of its duty to assess the facts of the case, whether and the extent to 
which the bacterium reacts to D-mannose. 
19 (2) The expert, whose findings were considered by the appeal court, also 
stated that it must be assumed that the binding of FimH to dissolved D-mannose 
molecules also initiates at least part of the biochemical processes for tissue 
invasion, which are ineffective, however, and cannot be identical to the response 
to the adhesion to surface structures of human cells containing D-mannose. On 
that basis, it has not been established that the interaction described by the appeal 
court, namely the triggering of biochemical processes as a reaction of the bacterial 
cell to the binding to D-mannose, causes the intended main effect of the substance 
at issue, namely to block the adhesion of bacterial cells to the bladder wall. 
Whether such causation is a prerequisite for the substance to have a 
pharmacological action is not apparent from the definition of pharmacological 
action in the MEDDEV Guidelines and requires clarification by the Court of 
Justice of the European Union. 
20 (3) In addition, the expert stated that (even) the reversible binding of D-
mannose to bacteria is accompanied by the creation of hydrogen bonds, which 
must not be regarded as a purely mechanical or physical mechanism. Rather, the 
specific adhesion of FimH to the glycosylated structures on the cell surface of the 
urinary tract initiates biochemical changes in the bacterial cell. The Chamber is of 
the opinion that the creation of hydrogen bonds described by the expert could also 
constitute an interaction within the meaning of the definition of pharmacological 
action in the MEDDEV Guidelines, which would also cause the intended main 
effect of the substance at issue. Whether that is the case also needs to be clarified. 
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21 bb) The appeal on a point of law unsuccessfully challenges the finding of the 
appeal court that the binding to a bacterium cannot be equated to an adhesion to a 
human target cell. It has been clarified by the case-law of the Court of Justice of 
the European Union and of the Chamber that a substance the molecules of which 
do not interact with a human cellular constituent may nevertheless, by means of its 
interaction with other cellular constituents present within the user’s organism, 
such as bacteria, viruses or parasites, have the effect of restoring, correcting or 
modifying physiological functions in human beings. A substance the molecules of 
which do not interact with a human cellular constituent may also constitute a 
medicinal product within the meaning of Article 1(1)(b) of Directive 2001/83/EC 
(see Court of Justice, GRUR 2012, 1167 (paragraph 31 et seq.) – Chemische 
Fabrik Kreussler; BGH, GRUR 2010, 1026 (paragraph 17) – Photodynamic 
therapy; GRUR 2015, 811 (paragraphs 4 and 9) – Mouthwash solution II). 
22 cc) The appeal on a point of law should also not be upheld in so far as it 
challenges the appeal court’s view that the existence of the required interaction 
does not depend on whether the binding of D-mannose to the bacterium (thus of 
the substance at issue to a cellular constituent) is reversible. 
23 (1) It has not yet been clarified in the case-law of the highest courts under 
which criteria pharmacological and non-pharmacological means can be 
distinguished in cases in which, as in the present case, the substance at issue is not 
absorbed by the target cell, but is bound only temporarily (see, in this regard, 
BVerwG, ZMGR 2021, 380, paragraph 11 et seq.); PharmR 2021, 593 
(paragraph 10 et seq.)). The definition contained in the MEDDEV Guidelines does 
not provide any indications that could lead to the conclusion that such binding 
must be permanent. That would suggest that the view taken by the appeal court, 
according to which, if such an interaction exists, the question of the reversibility 
of the adhesion to a cellular constituent is irrelevant, is correct. This also requires 
clarification by the Court of Justice of the European Union. 
24 (2) Contrary to the view taken in the appeal on a point of law, the dispute does 
not raise the question whether a pharmacological action can also be assumed in 
the case of a mere attachment of the active substance to the exterior of the cell if 
this does not lead to a change in the state or a function of the cell. The appeal 
court did not find the latter, rather it stated that a change in the transcription of 
various genes was observed in the bacterium in response to the binding of the 
FimH to structures containing mannose and that the bacterial cell reacts by 
biochemical processes to the binding of FimH to the surface structures containing 
D-mannose. In so doing, it affirmed a change in the function of the bacterial cell 
and the substance-induced triggering of a biochemical reaction inside the cell. 
25 b) The appeal on a point of law also contests the appeal court’s view that 
there is also no pharmacological action because the consequence of the – 
assumed – interaction is not, in accordance with the definition of the MEDDEV 
Guidelines, the blocking of another agent. 
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26 aa) The view taken in the appeal on a point of law is that the second alternative 
of the definition of ‘pharmacological action’ given in the MEDDEV Guidelines 
should cover cases in which, although there is no direct reaction in the sense of the 
first alternative, indirectly, as a result of the binding to a target cell, a (harmful) 
reaction to another messenger is blocked. However, the definition does not 
contain a ‘general clause’ according to which it is sufficient for the reaction of a 
human target cell to be prevented even indirectly, regardless of how that objective 
is achieved. The blocked substance must be an agent, thus a substance intended to 
exert a specific (harmful) effect on a target cell. In addition, the blocked agent 
must be different from the cellular constituent involved in the interaction, since 
the blocking of ‘another’ agent is required. Neither is the case here. It is not the 
bladder mucosa which is blocked, but the bacterium itself. In so far as 
inflammation of the bladder mucosa is prevented as a result, this is not the 
response of another agent but that of another receptor. The products therefore 
have no pharmacological action. 
27 bb) It is necessary to clarify whether the mode of action of D-mannose 
established by the appeal court may be regarded as blocking the response to an 
agent in accordance with the definition in the MEDDEV Guidelines or whether it 
rather – in accordance with the view taken in the appeal on a point of law – 
constitutes the blocking of the response to a receptor and therefore the conditions 
for the existence of a pharmacological action are not satisfied. 
28 (1) The appeal court proceeded on the basis that D-mannose causes the 
physiological processes of the bacteria, which accompany adhesion to human 
cells, to be blocked through the specific binding to the cell structures of those 
bacteria. The active substance blocks the adhesion of the FimH on the bacterium 
to mannosylated structures on the bladder wall. This could be interpreted broadly 
as blocking the response to another agent. The appeal court thus regarded human 
cell constituents, namely glycoproteins on cell membranes of the urinary tract, as 
another agent to which the response of the FimH is blocked. In order to be able to 
answer whether this is permissible, it is necessary to clarify the concept of ‘agent’ 
used in the MEDDEV Guidelines. 
29 (2) On the basis of the understanding of the term advocated in the appeal on a 
point of law, according to which an agent is a substance intended to exert a 
specific effect on a target cell, it is justified in objecting that glycoproteins on the 
cell membranes of the urinary tract cannot be regarded as agents because they do 
not exert any effect (for example on other cells). 
30 (3) In the Chamber’s view, the broad understanding of the term advocated by 
the appeal court appears convincing nevertheless. There is much to be said for a 
broad concept of ‘agent’ which generally describes a binding partner without 
specifying the material or structural nature of that binding partner. It seems logical 
that the binding partner may also be sourced from the human body. 
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31 Many medicinal products work in such a way as to block the response of a cellular 
constituent to parts of the human body. By way of example, the expert cited beta 
blockers, which block the adhesion of the body’s own adrenalin to the 
adrenoceptors (receptors in innervated tissue). Here too, there is no blocking of 
the response to another agent in the sense of the narrower understanding of the 
concept advocated in the appeal on a point of law. In addition, the expert referred 
to agents which were examined in the context of human immunodeficiency virus 
(HIV) infection therapy. So-called attachment inhibitors block the binding of 
glycosylated proteins of HIV to surface structures of human cells, which is 
necessary for an infection. The main mechanism of action is blocking the binding 
of pathogens and human cells. In this case too, the human cell or the receptor 
serving as a molecular binding partner on the cell would have to be regarded as an 
agent. 
32 cc) In so far as the appeal on a point of law emphasises that the blocked agent 
must be different from the cellular constituent involved in the interaction, since 
the definition of ‘pharmacological action’ given in the MEDDEV Guidelines 
refers to ‘another’ agent, it is not able to invalidate the line of argument of the 
appeal court. It found in addition to the relevant definition that D-mannose (the 
substance at issue) blocks the binding of FimH on the bacterium (receptor) and the 
mannosylated structures on the bladder wall (another agent). Moreover, according 
to the appeal court’s understanding, the blocked agent is therefore different from 
the cellular constituent involved in the interaction. 
33 5. The answer to the question referred for a preliminary ruling is material to 
the decision. 
34 a) The defendants’ appeal on a point of law cannot succeed merely because 
the appeal court carried out an incorrect overall assessment. 
35 aa) According to the case-law of the Court of Justice of the European Union 
and the Chamber, in order to assess whether products containing a substance 
which has a physiological effect are medicinal products by function in accordance 
with Article 1(2)(b) of Directive 2001/83/EC, a careful examination must be 
carried out of each individual case, taking into account not only the 
pharmacological, immunological or metabolic properties of the product but also 
all its other characteristics, such as its composition, the manner in which it is used, 
the extent of its distribution, its familiarity to consumers and the risks which its 
use may entail (see judgment of the Court of Justice of 30 April 2009 – C-27/08 
[2009], ECR I-3785 = GRUR 2009, 790 (paragraph 18) – BIOS Naturprodukte; 
Court of Justice, GRUR 2012, 1167 (paragraph 33 et seq.) – Chemische Fabrik 
Kreussler, with further references; BGH, PharmR 2016, 82 (paragraph 12) – 
Chlorhexidine). 
36 bb) The appeal court based its decision on that point, stating that, in the context 
of the required overall assessment, the manner in which the products are used 
militates in particular in favour of classifying the products as medicinal products 
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by function. In the case of medicinal products, it is customary for the products to 
be distributed with a leaflet in the packaging indicating the dosage and 
administration. They are marketed in a form which is also commonly used for 
medicines. They should also be used to support the treatment of an illness. 
Reference is made to side effects such as intolerance, nausea, bloating and loose 
stools. The extent of distribution is considerable. Although numerous criteria 
apply in the same way to medical devices, with the result that delimitation has to 
be primarily on the basis the determination of pharmacological properties, the 
overall assessment reveals that the products are medicinal products. 
37 cc) The challenges raised in the appeal on a point of law against that 
assessment of the facts of the case are ineffective. The appeal court carried out the 
overall assessment required by the case-law of the Court of Justice of the 
European Union and the Chamber, taking into account the relevant criteria in that 
regard, in a manner that is not objectionable from the perspective of an appeal on 
a point of law. In that regard, contrary to the view taken in the appeal on a point of 
law, it did not rely on the incorrect legal principle that a product is always a 
medicinal product by function when it has a pharmacological action. Furthermore, 
in so far as it is claimed in the appeal on a point of law that the appeal court failed 
to take account of the fact that the absence of risks associated with use militates 
against classification as a medicinal product by function, this is not consistent 
with the finding of the appeal court which is accepted in the appeal on a point of 
law, according to which the products have various side effects which are listed in 
detail. 
38 b) The answer to the question referred for a preliminary ruling is also a 
precursor of the other complaint in the appeal on a point of law, by which it 
challenges the appeal court’s assertion that, under normal conditions of use, the 
products appreciably restore, correct or modify physiological functions in human 
beings. 
39 aa) According to the case-law of the Court of Justice of the European Union 
and the Chamber, to be capable of being regarded as being a medicinal product by 
function, the product in question must, having regard to its composition and if 
used as intended, be capable of appreciably restoring, correcting or modifying 
physiological functions in human beings by exerting a pharmacological, 
immunological or metabolic action (see Court of Justice, GRUR 2012, 1167 
(paragraphs 30 and 35) – Chemische Fabrik Kreussler; BGH, GRUR-RR 2013, 
272 (paragraph 7); PharmR 2016, 82 (paragraph 12) – Chlorhexidine, both with 
further references). 
40 bb) The appeal court affirmed this on the ground that the blocking of FimH on 
the bacterial surface has the effect of preventing bacteria from binding to the cell 
membrane, which thwarts the biochemical reaction between the bacterium and the 
host cell, with the result that the physiological function of the human body is 
influenced as the onset or progression of the inflammation of the urinary tract is 
repressed. The fact that the clinical significance of the therapy and prevention 
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remains unclear due to a lack of sufficient data does not preclude that outcome. 
According to the expert’s findings, it has been proven beyond doubt that D-
mannose binds to FimH and thus undermines the physiological processes of the 
bacterium and the pathophysiological processes of the urinary tract infection. 
41 cc) That view is countered in the appeal on a point of law, which argues that 
the influence inherent in a therapeutic or preventive effect on physiological 
functions is not, in itself, sufficient for the assumption of a medicinal product by 
function; rather, the intended therapeutic purpose must be achieved by significant 
interference with the physiological functions of human beings, which in turn must 
be classified as pharmacological. That is not the case with D-mannose, which 
binds to bacteria solely by reversible, physical means without destroying them and 
also does not interact with the human bladder mucosa. 
42 dd) According to the aforementioned case-law of the Court of Justice of the 
European Union, the appreciable influence on physiological functions required for 
the assumption of a medicinal product by function presupposes a pharmacological 
action (or an immunological or metabolic action, which, however, is not at issue 
in the present case) (see Court of Justice, GRUR 2012, 1167 (paragraph 30) – 
Chemische Fabrik Kreussler, with further references). The pharmacological (or 
immunological or metabolic) properties of a product are the factor on the basis of 
which it must be ascertained, in the light of the potential capacities of the product, 
whether it may, for the purposes of Article 1(2)(b) of Directive 2001/83/EC, be 
administered to human beings with a view to making a medical diagnosis or to 
restoring, correcting or modifying physiological functions in human beings 
(judgment of the Court of Justice of 15 November 2007, C-319/05 [2007], ECR I-
9811 (paragraph 59) = EuZW 2008, 56 – Commission v Germany; Court of 
Justice, EuZW 2009, 545 (paragraph 20) – BIOS Naturprodukte, both with further 
references). Assuming that the appeal court was right to find that there was a 
pharmacological action, its assessment that the products appreciably restore, 
correct or modify physiological functions in human beings is not open to objection 
from the perspective of an appeal on a point of law. 
43 c) An answer to the question referred for a preliminary ruling is also 
necessary for that reason, since, in addition to the classification of the products at 
issue as medicinal products by function, their classification as medicinal products 
by presentation could also be considered (see, in this regard, Court of Justice, 
PharmR 2023, 160 paragraphs 49 to 51 – Bundesrepublik Deutschland (Nasal 
drops)). In the appeal on a point of law, it is necessary to examine only whether a 
medicinal product by function is present, since the appeal court based the 
judgment on that factor alone. Moreover, the judgment cannot be upheld from the 
point of view of the existence of a medicinal product by presentation, since the 
appeal court did not make sufficient findings in that respect. 
44 d) Lastly, the fact that the legal opinion of the appeal court is in line with the 
assessment of the European Commission, as expressed in its manual on borderline 
products (version 1.2 (05-2019), point 4.20), does not render an answer to the 
CASSELLA-MED AND MCM KLOSTERFRAU 
 
13 
question referred for a preliminary ruling obsolete either. In that manual, the use 
of D-mannose to prevent urinary tract infections was mentioned as an example of 
a pharmacological (and not a physical) action of a medicinal product. However, 
the views of the Commission expressed in the manual are not binding […]. On the 
contrary, it expressly states that only the Court of Justice of the European Union 
can give an authoritative interpretation of Community law […]. 
[…]