Amgen’s subsidiary Immunex has filed a lawsuit against Sanofi and Regeneron alleging patent infringement with the duo’s recently-approved eczema drug Dupixent.
Dupixent (dupilumab) – an interleukin-4 (IL-4) and IL-13 inhibitor – was approved for eczema (atopic dermatitis) patients who do not respond to or should not use topical prescription therapies last month. It is one of the hottest prospects in Sanofi and Regeneron’s pipeline with analysts predicting peak sales of up to $3bn.
Immunex claims that it will suffer damages as a result of Sanofi and Regeneron’s ‘infringing activities’ with Dupixent, but its lawsuit was filed in response to a ‘keep-away’ suit – filed by Sanofi and Regeneron last month – seeking an early judgment that Dupixent does not trespass on Immunex’ patent estate.
“Sanofi and Regeneron wish to eliminate any potential obstacle Amgen might seek to raise against the planned US commercialisation of Dupixent,” said the pair in that earlier complaint.
This is the second major legal spat between the parties, which are already locked in litigation over their cholesterol-lowering PCSK9 inhibitor drug. In February a US appeals court suspended an injunction barring the sale of Sanofi and Regeneron’s PCSK9 inhibitor Praluent (alirocumab), after Amgen won a ruling that Praluent infringed two patents covering its own PCSK9 inhibitor Repatha (evolocumab).
On this occasion Amgen does not have a direct competitor to Dupixent in the pipeline or on the market, so it is not seeking an injunction on sales of Dupixent but would like financial recompense for its intellectual property. The company had previously explored developing asthma drugs based on IL-4 receptor antagonists.
Specifically Immunex says it has a US patent (No. 8,679,487) covering the use of antibodies targeting the IL-4 receptor and a specific molecule – 12B5 – which it claims Regeneron used in its own discovery efforts that resulted in the identification of dupilumab.