Turning point for Spanish Merger Control – CNMC issues first–ever prohibition decision

At the beginning of this year, the National Authority for Markets and Competition in Spain (“CNMC”) initiated Phase II proceedings in relation to a proposed transaction in the nuclear medicine sector concerning radiopharmaceuticals for cancer detection (See Case C/1501/24 CURIUM/IRAB). 

After an in-depth investigation, the CNMC prohibited the transaction on 6 October 2025, marking the first time since its establishment in 2013 that Spain’s competition authority has blocked a merger.

Relevant market structure and CNMC’s investigation

The transaction involved the acquisition of exclusive control of Instituto de Radiofarmacia de Barcelona ("IRAB") by Curium. Both companies are active in the markets for the supply of radiopharmaceuticals for the performance of positron emission tomography ("PET") and contract manufacturing services ("CMO") of such products.

Because PET pharmaceuticals have a short shelf life due to radioactive decay, the CNMC focused its analysis on potential competitive effects in Catalonia and Spain’s North-East region, where IRAB’s Barcelona operations directly competed with Curium. During Phase I of the merger review, the CNMC found that the transaction could significantly reduce competitive alternatives by eliminating a key competitor. This finding was in part due to the markedly local nature of IRAB’s operations and the fact it had just one cyclotron in Barcelona —a particle accelerator essential for manufacturing these products.

Following this initial assessment, the CNMC initiated Phase II proceedings on 7 February 2024 and conducted an in-depth investigation of the competition concerns they had identified. The CNMC investigation confirmed that the affected markets were highly concentrated and that the transaction posed serious competition concerns.

Identified competition issues in favour of prohibiting the merger

Based on a detailed market study of the parties’ overlapping activities, the CNMC considered that there were a number of relevant factors that should lead to the prohibition of the merger:

1. The acquirer’s market power: Whilst Curium's radiopharmaceutical portfolio was already extensive prior to the transaction, according to the CNMC, the acquisition of IRAB’s business would have allowed Curium to strengthen its dominant position in most PET radiopharmaceutical markets in which it has already a solid presence. It would also expand its geographic scope of activity in Catalonia and neighboring regions. Curium's consolidation in these markets may have generated portfolio-related risks that limit the ability of its competitors to compete efficiently, given the notifying party's portfolio would be impossible to replicate after the transaction.
2. Innovation in the market: IRAB is currently an international reference center in radiopharmaceutical research for third parties and the only “neutral and independent” PET radiopharmaceutical research entity in Spain.  According to the CNMC, the transaction could also pose risks to innovation by reducing innovation in the manufacture and commercialisation of PET radiopharmaceuticals in Spain and eliminating or significantly limiting potential competition in certain markets. Furthermore, for third parties, this would mean the elimination of an independent research company, which would likely reduce future R&D activity in Spain.
3. Reduction in the supply of key products: The CNMC also assessed the impact that the transaction would have on the manufacture and commercialisation of radiopharmaceuticals that Curium currently performs for third parties. These third parties compete with products manufactured and commercialised by IRAB. The CNMC considered that Curium might prioritise synthesising its own radiopharmaceuticals over those of third parties and/or restrict supply or access to certain products for third party companies, potentially reducing the range of options available for prostate cancer diagnosis.
4. Barriers to entry: The potential anti-competitive effects identified were aggravated by the high barriers of entry to the market.  Beyond regulatory hurdles, the key challenge in this case is the need for a cyclotron. Cyclotrons cost between EUR 2 and 7 million, and commissioning one takes several years before it becomes fully operational. In fact, only four operators in Spain have a relatively extensive portfolio of PET radiopharmaceuticals, of which only three (two of them being the parties participating in the transaction) own or manage cyclotrons.

Commitments presented to the CNMC

In its attempt to resolve the competition concerns identified by the CNMC, Curium offered a series of commitments including the following: 

1. To refrain from manufacturing or commercialising the relevant products from IRAB’s facilities until other competitors were effectively marketed in north-eastern Spain;
2. To continue manufacturing certain IRAB’s products for prostate cancer under the same conditions for a minimum period of time;
3. To increase production for certain products manufactured for third parties at IRAB’s facilities;
4. To offer standard market-condition service levels for any new third-party CMOs; and
5. To enhance IRAB’s cyclotron production capacity.

Despite Curium’s efforts to address the competition issues identified during the merger control proceedings, the CNMC concluded that the remedies presented were insufficient and incapable of resolving the structural risks raised by the transaction (both horizontal and vertical). This was due to limited duration and potential risks of higher prices, stronger barriers of entry, and coordinated effects on the market. As a result, the CNMC prohibited the transaction.

Stricter antitrust enforcement 

The decision emphasises the CNMC's focus on highly concentrated markets affecting relevant public interests, like health and innovation. It effectively recognises that the loss of an independent research and development partner can have long-term detrimental effects on market dynamics beyond immediate horizontal overlaps.

This decision highlights a growing tendency towards stricter, and more in-depth, merger control enforcement. However, the decision is not final. Under Spanish competition law, the CNMC’s Minister of Economy, Trade and Business must be notified of the decision, and the Minister ultimately has the discretion to refer it to the Council of Ministers. If referred, the Council of Ministers might override the decision based on broader public interest considerations beyond competition law concerns. Generally, this mechanism is particularly relevant in heavily regulated sectors with critical public health implications that have a direct impact on consumer welfare, particularly those involving innovative technologies or products.

If you need more information or further guidance in this area, please contact Candela Sotés and Pablo Rodríguez.

VISIT OUR COMPETITION LAW HOMEPAGE