Polpharma and Wuesthoff succeed in revoking MS drug patent

US biotechnology company Biogen owns several patents pertaining to the treatment of relapsing-remittent multiple sclerosis. This includes EP 2 676 967, which covers methods of using the drug natalizumab, sold under the brand name Tysabri. The patent expires in February 2023.

Natalizumab treats multiple sclerosis in patients who test negative for John Cunningham Virus (JCV) infection. However, the Opposition Division of the EPO has revoked Biogen’s EP 967. This could pave the way for a new Sandoz/Polpharma biosimilar to enter the market.

Biogen faces competition

EP 967 covers natalizumab as used to treat inflammatory or autoimmune diseases. For example, where plasma or serum from a blood sample is tested for the presence of IgG antibodies to anti-John Cunningham virus (JCV). IgG antibodies, the most common antibodies, are found in blood and other fluids. They protect the body against various viruses and bacterial infections.

EP 967 also requires that a doctor can initiate treatment for MS, if serum from a blood sample is negative for IgG antibodies to JCV. However, patients who test anti-JCV antibody positive have a higher risk of developing progressive multifocal leukoencephalopathy (PML).

Until 2019, Biogen’s Tysabri had dominated the market for the treatment of relapsing-remitting multiple sclerosis. However, in 2019, Polpharma and Sandoz reached an agreement that the former will take over the global commercialisation for a proposed natalizumab biosimilar. The biosimilar is currently undergoing Phase III clinical trials, which should be completed by August 2021.

Waiting for European Medicines Agency (EMA) approval may extend the timeframe. Regardless, Biogen could experience competition for Tysabri as early as the end of 2022.

EPO decides no inventive step

In related cases, the Opposition Division has also revoked EP 27 15 352, which covers assessing the risks of PML, and EP 19 91 267, which covers methods of treating inflammatory and autoimmune diseases with natalizumab. Both patents pertain to diagnostic methods and medical use claims.

In this instance, the Opposition Division revoked EP 967 for lack of inventive step. It also considered matters of novelty and added matter.

Regarding inventive step, the division decided that EP 967’s Auxiliary Request 1 lacks inventive step over the prior art. The prior art, in this instance, is a scientific article published by J.D. Berger in 2005. As such, according to the examiners, a person skilled in the art would be unaware that presence of IgG antibodies is a risk-marker in some MS patients.

In terms of inventive step, the division decided that Biogen omitted a monitoring step, which formed part of the original filed patent application, in the patent’s claims. However, Biogen still has five divisional patents pending.

Hendrik Wichmann

Excellent connections

Previously, df-mp’s patent attorneys have conducted patent litigation for Biogen. In the revocation case concerning EP 967, the firm represented Biogen in the opposition proceedings.

The Munich law firm has excellent connections to Biogen, which developed Tysabri together with Irish company Elan. Biogen then bought a 50% stake in Elan in 2013.

Df-mp had already fought on Biogen’s behalf over Tecfidera, another US multiple sclerosis drug.

Sandra Pohlman

For Polpharma, Hendrik Wichmann of Wuesthoff & Wuesthoff coordinates the Europe-wide attacks on Biogen’s patent rights.

Polpharma and Wuesthoff have worked together since 2014, when the company first instructed the law firm regarding a series of nullity suits against Biogen in Europe.

For Biogen
df-mp Dorries Frank-Molnia & Pohlman (Munich): Sandra Pohlman (patent attorney)

For Polpharma
Wuesthoff & Wuesthoff (Munich): Hendrik Wichmann, Julia Reinert, Simon Mügge (Finland) (all patent attorneys)

EPO Opposition Division, European Patent Office, Munich
Maaike van der Kaaij (chairman), Ivo Galli, Beatriz Montero Lopez (both members)