Alexion defends market exclusivity for orphan drug Soliris against Amgen

Pharmaceutical manufacturers can sue competitors for market exclusivity for an orphan drug. This was the outcome of a decision by Munich Regional Court in the dispute between Alexion and Amgen over the biologic Soliris for the treatment of rare blood diseases. The court thus confirmed a previously issued preliminary injunction.

Orphan drugs treat rare diseases. They receive ten years of market exclusivity in the European Union in addition to patent protection, so as to promote the development of corresponding active ingredients and treatments.

The US pharmaceutical company Alexion markets such an orphan drug, the biologic Soliris. It is based on the monoclonal antibody eculizumab and is used for the treatment of paroxysmal nocturnal haemoglobinuria (PNH). PNH is a rare blood disorder that occurs when the immune system destroys the red blood cells and platelets. Left untreated, PNH can cause haemolytic anaemia, chronic kidney disease or thrombosis. Soliris also treats other diseases such as atypical haemolytic uraemic syndrome (aHUS), generalised myasthenia gravis and neuromyelitis optica.

Market exclusivity for treating PNH has now expired.

Concerns over cross-label use

In August 2022, Amgen announced the development of ABP 959, a biosimilar candidate to Soliris for the treatment of PNH. According to the company’s statement, ABP 959 has “the same pharmaceutical form, dosage strength, route of administration and dosing regimen as licensed monoclonal antibody eculizumab in the US and the EU”.

In April 2023, Amgen received EU marketing authorisation from the European Medicines Agency for its eculizumab product ABP 959.

Accordingly, the biosimilar, now marketed under the brand name Bekemv, is approved exclusively for the treatment of PNH for which the market exclusivity of the original product Soliris has expired.

Therefore, Alexion did not question the approval of Bekemv in the current dispute. Rather, the US company is concerned with preventing possible cross-label use of the biosimilar for other indications.

Cross-label use would mean that, despite Bekemv having only obtained market approval for the treatment of PNH, doctors and pharmacies could prescribe the drug for the other treatments for which market exclusivity continues.

Ex parte PI confirmed

Alexion initially obtained an injunction from Munich Regional Court in May 2023 to prevent off-label use. Amgen had to take various measures to ensure Bekemv was not used to treat any of the three indications that are still protected. Amgen appealed against this ex parte decision.

Now, the current decision from the 21st Civil Chamber, led by presiding judge Georg Werner, has confirmed the ex parte PI (21 O 6235/23) and largely upheld the stipulated measures.

Orphan drugs commercially significant

The stakes are high for Alexion. According to a report in PharmaForum, Soliris accounted for four fifths of the pharma innovator’s revenue in the last quarter.

In the court case, Amgen’s representatives argued that the restrictions imposed by the court to prevent cross-label use made it impossible for Amgen to market Bekemv in Germany for its approved use in the treatment of PNH. For this reason, Amgen is currently not marketing its eculizumab product in Germany.

The dispute between Alexion and Amgen was thus not a classic patent dispute. Rather, it focused on whether market exclusivity for an orphan drug can be enforced not only against regulatory authorities, but also against competitors in civil proceedings.

Interpretation of EU regulation

According to article 8 of the EU regulation 141/2000 on orphan medicinal products, “where a marketing authorisation in respect of an orphan medicinal product is granted (…) the Community and the Member States shall not, for a period of 10 years, accept another application for a marketing authorisation, or grant a marketing authorisation or accept an application to extend an existing marketing authorisation, for the same therapeutic indication, in respect of a similar medicinal product”.

Amgen had argued that this only concerns the prohibition of approval under public law. Therefore, an action against a regulatory authority, for example, to enforce the market exclusivity of an orphan drug would be permissible. In Amgen’s view, however, a civil law prohibition claim against competitors cannot be derived from this.

Unique judgment

However, the judges of the 21st Civil Chamber interpreted the EU regulation differently. According to them, the right to market exclusivity also includes the protection of orphan drugs against impairment or infringement by competitors. In the opinion of the court, the regulation aims to create a legal position that goes beyond mere approval.

According to the judges and lawyers involved, this is the first time a court in Europe has ruled on the question of whether the market exclusivity of orphan drugs can also be enforced against competitors. Similar incentives for the development of orphan drugs have existed in the US since 1983 and in Japan since 1993, but there is no known case in these countries where market exclusivity has been enforced in this form against a competitor.

Amgen appealed the PI earlier this week.