Ahmedabad-based Cadila Healthcare Ltd (Zydus Cadila) is facing lawsuits in various US courts, including one filed by global pharma major Novartis Pharmaceuticals, for infringement of patents. Novartis has filed two suits against Cadila Healthcare’s US subsidiaries Zydus Noveltech and Zydus Pharmaceuticals (USA), accusing them of infringing patents relating to a drug that treats Alzheimer’s and Parkinson’s disease. A similar suit has been filed by Roxane Laboratories Inc in a New Jersey court against Zydus Cadila for infringement of patent for a drug used to treat patients with end-stage renal failure. In a lawsuit filed at the US District Court Delaware, Switzerland-based Novartis has accused Zydus Cadila and its US subsidiaries Zydus Noveltech and Zydus Pharmaceuticals of infringing two of its patents. The Swiss company alleged the Abbreviated New Drug Application (ANDA) filed by Zydus Cadila before the US Food and Drug Administration would infringe its US patents 6,316,023 (‘023) and 6,335,031 (‘031) for Exelon Patch, which is used for the treatment of mild-to-moderate dementia of the Alzheimer’s and Parkinson’s disease.
The ANDA is for commercial manufacture, use, import and sale of the drug. Novartis added that Zydus Cadila’s application claimed its patents were invalid and or would not be infringed. However, it did not allege any of the claims were unenforceable.
Commenting on the developments a source in Zydus Cadila indicated that this is a routine process to get ANDA approvals in the US market. "Basically, it is a routine process by pharmaceutical companies who seek to get the 180-day exclusivity period to market a drug whose patent expiration date is near. Several companies rush to file the ANDAs in order to be one of the first applicants to get the nod of the US drug regulator to market a drug in the country," said Sarabjit Kaur Nangra, pharma analyst with Angel Broking.
Any innovative pharma company would immediately react to the ANDA filing and their first argument would be that of patent infringement, and whoever wins the legal battle gets the right to market the drug in the US, she added.
Zydus Pharmaceuticals Inc (a wholly owned subsidiary of Cadila Healthcare) was earlier challenged in the US by Pfizer Inc in 2012 when it sought approval to market the generic version of the latter's anti-depressant drug Pristiq prior to the expiration of patent in the US. Pfizer had filed a lawsuit in a US district court against Zydus' abbreviated new drug application (ANDA).
Other Gujarat-based pharma companies who enjoy a significant presence in the US have earlier engaged in such legal battles to get marketing rights for drugs in the US. For example, Alembic had filed ANDA for desvenlafaxine succinate (Pristiq) in 2013 and it expected to share the 180-day exclusivity period with other companies who also get a nod.
Usually, when a block-buster patented drug goes off-patent, there is some price erosion, however, still there remains significant demand for the generic version, and hence the rush by companies.