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Abuse of dominance by disparagement: The CMA's investigation into Vifor Pharma

Posted on 17 October 2025

Introduction 

On 23 May 2025, the Competition and Markets Authority ("CMA") published its decision to accept commitments offered by Vifor1 following an investigation2 into suspected anti-competitive behaviour in the supply of intravenous (''IV") iron medicine in the UK.3 The investigation involved an alleged abuse of dominance concerning the disparagement of competing products to reduce competition in the market for high-dose IV iron. While the pharmaceutical industry has been highly scrutinised for many years, competition authorities have typically been concerned with pay-for-delay agreements with generic pharmaceutical companies, excessive pricing, or killer acquisitions (being the acquisition of small, innovative targets with the aim of preventing their market entry). The Vifor investigation therefore marks a significant development in the CMA's decisional practice, reflecting a broader shift towards addressing subtler, less conventional conduct that may be regarded as anti-competitive. 

Background 

In June 2022, the European Commission (the "Commission") opened an investigation into Vifor for suspected abuse of dominance under Article 102 of the Treaty on the Functioning of the European Union ("TFEU").4 This investigation followed concerns by the Commission that between the period 2010-2022 Vifor disseminated objectively misleading information about the safety of a competing IV iron medicine (rival Pharmacosmos's product, Monofer) to healthcare professionals, thereby hindering its market entry and/or uptake. Monofer and Vifor's own high-dose IV iron medicine (known as Ferinject) are used in the treatment of iron deficiency and anaemia.  

Disseminating objectively misleading information includes the dissemination of inaccurate information and extends to information that, while technically correct, is presented incompletely and is capable of confusing or manipulating public perception.5 Following a review of evidence, the Commission expressed preliminary concerns that Vifor had engaged in a two-fold communication campaign intended to disseminate misleading information about Monofer to manipulate public perception regarding its safety and risks. This related firstly to Monofer's status as a "dextran-based" medicine, which was used to invoke "historical negative safety connotations" surrounding dextran-induced anaphylactic reactions and an "unacceptably high rate of serious adverse events" associated with dextran-based medicines.6 Examples of the misleading information included claims that "Ferinject is the only high-dose IV iron that is non-dextran based" which the Commission described as inaccurate.7 The Commission noted that the second aspect of Vifor's communication campaign included messaging that Monofer was a more dangerous treatment than Ferinject due to an increased risk of HSR (a hypersensitivity reaction of the immune system to an antigen or allergen, which can, in its most severe form, include anaphylactic reactions), irrespective of whether these reactions were linked to dextran.8 The Commission did not make a formal finding of infringement, but after expressing its concerns, subsequently closed its investigation by adopting commitments offered by Vifor in July 2024, which included: 

  • launching a multi-channel communication campaign to rectify and undo the effects of Vifor's potentially misleading messages relating to the safety of Monofer; 
  • agreeing not to engage in external promotional and medical communications about Monofer's safety using information which is not based on Monofer's label or derived from clinical trials which are specifically designed to compare Ferinject and Monofer across the entire EEA; and  
  • implementing several measures and safeguards to ensure compliance with the commitments, including staff training, internal mechanisms to ensure that external promotional and medical communications and internal training materials align with the commitments, and a system to certify compliance.  

CMA investigation 

In 2024, the CMA opened an investigation into whether Vifor abused its dominant position in the supply of IV iron deficiency treatments for NHS patients in the UK between 2010-2024.9 The CMA's investigation echoed the Commission's concerns and followed several decisions by the Prescription Medicines Code of Practice Authority and its Appeal Board in the UK between 2008-2024, which found that Vifor had disseminated misleading claims about the safety of Monofer and Ferinject.10 The CMA concluded that Vifor held a dominant position in the UK for the supply of high-dose IV iron between 2010-2024 given that: 

  • the market share of Ferinject was consistently above 50%; 
  • Ferinject was sustainably sold at a price premium compared to Monofer; and 
  • the market had high barriers to entry, particularly in relation to the time and investment required to develop and introduce a competing product, and to establish a reputation for safety.11  

Like the Commission's investigation, the misleading claims regarding Monofer's safety concerned its categorisation as a dextran-based or dextran-derived product and its alleged association with a higher incidence of hypersensitivity reactions.12 The CMA found that by making misleading statements Monofer's safety and characteristics, Vifor did "not compete on the merits".13 It was accordingly not necessary for the CMA to prove that recipients were in fact misled by Vifor's misleading claims, but rather that the claims were capable of restricting competition. The CMA described Vifor's strategy as being "designed with the objective of hindering the uptake of a competing product" which constituted strong evidence that its claims were capable of hindering competition.14 

Acceptance of commitments  

In December 2024, the CMA published a Notice of intention to accept commitments offered by Vifor and opened a consultation to invite responses from interested third parties.15 The consultation closed on 17 January 2025, following which the CMA published its final commitments decision on 23 May 2025.16 To alleviate the CMA's concerns, Vifor has committed to: 

  • contribute a voluntary payment of £23 million to the NHS; 
  • correct any potentially misleading communications disseminated by Vifor relating to the safety of Monofer and Ferinject, through a multi-channel communications campaign to healthcare professionals; and  
  • initiate several compliance measures to prevent the future dissemination of misleading communications relating to the safety of Monofer and Ferinject to healthcare professionals. 
  • The term of the Commitments will be until 22 July 2034, which is intended to align with the commitments offered by Vifor to the Commission, and an independent trustee will monitor Vifor's compliance in the UK.17 

Key takeaways  

As the first standalone disparagement investigations by UK and EU regulators, the Vifor investigations mark a significant development in competition authorities' decisional practice of regarding abuse of dominance cases. These investigations reflect competition authorities' increasing vigilance regarding novel and more nuanced forms of anti-competitive behaviour. Vifor's commitments, particularly the communication campaigns it must conduct to reverse the effects of its misleading messages, illustrate that the ramifications of disparagement are significant not only from a legal and financial perspective, but also from a commercial and reputational angle. 

Comprising Vifor Pharma UK Limited, Vifor Pharma Management Limited, Vifor Pharma Limited and CSL Limited (collectively "Vifor")
Case 51377 (Vifor Pharma)
The CMA's Decision to accept commitments offered by Vifor in relation to the supply of high-dose IV iron dated 23 May 2025
Case AT40577, concerning the disparagement of the treatment Monofer, sold by Pharmacosmos A/S
Paragraph 84 of the Commitments Decision of the European Commission in Case AT40577
ibid, paragraphs 93 -96
ibid, paragraph 103
ibid, paragraphs 148 and 149
See the CMA's press release announcing the launch of its investigation on 31 January 2024
10 Paragraph 3.21 of the CMA Commitments Decision in Case 51377
11 ibid, paragraph 3.17
12 ibid, paragraph 3.20
13 ibid, paragraph 4.8
14 ibid, paragraph 4.10
15 See the CMA's Notice of intention to accept commitments and the CMA's consultation dated 10 December 2024
16 n(3)
17 ibid, paragraphs 5.11-5.12

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