Italy's competition watchdog has opened a formal investigation into pharmaceutical giant Biogen over allegations the company is blocking cheaper alternatives to its multiple sclerosis drug, a tactic that could cost the Italian National Health Service tens of millions in potential savings.
The Autorità Garante della Concorrenza e del Mercato (AGCM), Italy's antitrust authority, announced the probe on May 27, targeting both Biogen Italia S.r.l. and its U.S.-based parent Biogen Inc. The core allegation: Biogen is leveraging control over a mandatory diagnostic test to prevent patients from accessing a less expensive biosimilar medication manufactured by Sandoz, effectively locking out competition in violation of Article 102 of the Treaty on the Functioning of the European Union.
Why This Matters
• Public health cost: The biosimilar drug costs at least 20% less than Biogen's version, potentially saving Italy's healthcare system 47.7 M euros over five years.
• Patient access: Roughly 8,000 Italian patients are projected to need natalizumab treatment by end-2026, making pricing disputes critical.
• Legal precedent: If proven, this could set new boundaries for how pharmaceutical companies bundle diagnostic tools with drugs in Italy.
Impact on Residents and Patients
For the estimated 8,000 Italians living with severe multiple sclerosis who depend on natalizumab, the outcome of this investigation could determine both the sustainability of their treatment and the strain on public resources.
If the AGCM's allegations are upheld and Biogen is compelled to decouple the Stratify test from Tysabri purchases, patients and physicians would gain genuine choice. Neurologists could prescribe Tyruko without sacrificing access to essential safety monitoring, and the SSN could redirect savings toward expanding access to other treatments or covering more patients.
Conversely, if Biogen's bundling strategy continues unchallenged, Italy risks remaining locked into higher drug costs even as patent protections expire—a scenario that undermines the fundamental promise of biosimilar competition.
If you are currently being treated with natalizumab or have family members in this situation, you can track updates on this investigation through the AGCM's official website or consult your neurologist for guidance on how the case may affect your treatment options.
The Drug at the Center of the Dispute
Natalizumab is a specialized therapy prescribed to multiple sclerosis patients with severe, rapidly progressing forms of the disease. For over 15 years, Biogen's Tysabri was the only natalizumab-based medication on the market, giving the company an effective monopoly.
That changed in 2024 when Biogen's patent protections expired. Sandoz immediately moved to commercialize Tyruko, a biosimilar version that offers the same therapeutic effect at a fraction of the cost. During the first nine months of 2025, Tyruko was priced at an average of 956.9 euros per package, compared to 1,200.83 euros for Tysabri.
Biosimilars are not generic copies but highly similar biological medicines that meet rigorous equivalence standards set by the European Medicines Agency. Their introduction typically drives down costs across healthcare systems.
The Test That Became a Barrier
The investigation centers on a diagnostic procedure known as the anti-JCV test, marketed by Biogen under the brand name Stratify. Natalizumab carries a rare but serious risk: it can trigger progressive multifocal leukoencephalopathy (PML), a devastating brain infection caused by the John Cunningham virus (JCV).
Before starting natalizumab therapy and at regular intervals during treatment, patients must undergo the anti-JCV test to assess their infection risk. Until 2022, Stratify was the only authorized screening tool in Italy. While alternative anti-JCV tests have since received regulatory approval, Stratify remains the de facto standard among neurologists and healthcare providers due to its established use protocols and physician familiarity. This continued reliance makes Biogen's alleged control over test access particularly consequential for the current case.
According to the AGCM, Biogen holds a dominant position in the market for this diagnostic test. The authority alleges that Biogen is now tying access to the Stratify test exclusively to purchases of Tysabri, refusing to make it commercially available for patients treated with Sandoz's Tyruko.
This creates a dilemma for physicians and patients: even if Tyruko is clinically equivalent and cheaper, switching to it becomes impractical if the required safety monitoring tool remains inaccessible.
What This Means for Italy's Healthcare System
The Italian National Health Service (SSN) operates under tight budget constraints, and drug costs represent a significant line item. The AGCM estimates that blocking the Tyruko biosimilar from gaining market share would eliminate savings of at least 20% on natalizumab prescriptions.
Over the five-year period from 2024 to 2028, the introduction of natalizumab biosimilars was projected to reduce SSN spending by 47.7 M euros, with savings accelerating over time—from 3.1 M euros (1.8% reduction) in the first year to 15.1 M euros (7.7% reduction) by year five.
Those figures assume competitive access. If Biogen's alleged bundling strategy succeeds, the SSN would continue paying premium prices for a drug that now has a cheaper, clinically equivalent alternative.
The patient population is also growing. Projections indicate 7,779 natalizumab patients in 2025, rising to 8,090 in 2026. Each additional patient locked into the more expensive therapy multiplies the fiscal impact.
Guardia di Finanza Raids and Corporate Response
On May 26, AGCM officials, accompanied by the Nucleo Speciale Antitrust of the Guardia di Finanza (Italy's financial crimes police), conducted inspections at Biogen's Milan offices. The raid underscores the seriousness of the investigation and the authority's intent to gather internal documentation.
Biogen issued a brief statement confirming it is "fully cooperating with the authorities." The company has not publicly contested the facts outlined by the AGCM but has not admitted wrongdoing either. Sandoz has declined to comment beyond confirming its commitment to bringing Tyruko to market.
Potential Sanctions and Legal Precedents
Violations of Article 102 TFUE, which prohibits abuse of a dominant market position, can result in substantial fines. While the AGCM has not yet specified potential penalties, European antitrust authorities have historically imposed fines reaching into the hundreds of millions of euros for similar conduct.
In 2020, the European Commission fined Teva Pharmaceutical approximately 462 M euros for delaying generic competition for its multiple sclerosis drug Copaxone through patent manipulation. In another case, Novartis, Roche, and Genentech were penalized by French regulators for denigrating a lower-cost alternative to protect sales of a premium product.
The Biogen case is notable because it involves a diagnostic tool rather than a drug patent, expanding the frontier of antitrust enforcement in pharmaceuticals. If the AGCM's theory holds, it could establish that bundling mandatory medical tests with proprietary drugs constitutes an unlawful barrier to biosimilar competition.
The Broader European Context
Italy's investigation unfolds against a backdrop of intensifying scrutiny on pharmaceutical pricing across Europe. The European Medicines Agency approved a record 41 biosimilars in 2025, reflecting both regulatory momentum and industry response to cost pressures.
Biological drugs—complex medications derived from living cells—account for roughly 40% of total pharmaceutical spending in Europe, and that share is rising. The introduction of biosimilars has historically driven down costs; in the autoimmune biologics market, the average quarterly cost per patient fell 40% from 2016, with biosimilar penetration reaching 89%.
However, experts warn of a looming "biosimilar void" for products with annual EU sales below 500 M euros, where only 7% are expected to face competition over the next decade, leaving an estimated 7 billion euros in potential savings unrealized. Natalizumab's sales figures place it in a category where biosimilar competition is economically viable—making any artificial barriers particularly costly.
The investigation remains in its early stages, with no timeline announced for a final decision. Both companies are expected to submit detailed responses to the AGCM's preliminary findings in the coming months.
