AstraZeneca challenges Aurobindo’s proposed Nexium generic

AstraZeneca has sued Aurobindo Pharma Limited and its US-based subsidiary Aurobindo Pharma USA Inc for infringing four of its patents related to heartburn drug Nexium.

The case was filed after Aurobindo made an Abbreviated New Drug Application (ANDA) with the US Food and Drug Administration that requested approval to make and sell a generic delayed-release version of Nexium (esomeprazole magnesium) in 20 mg and 40 mg form before expiry of AstraZeneca’s patents.

One of the Nexium patents at issue is due to expire in 2015. The other three will expire in 2018.

In the action brought at the US District Court for the District of New Jersey on December 3, AstraZeneca asked for judgment that the patents are valid and enforceable and infringed by Aurobindo’s generic. It also requested a permanent injunction stopping Aurobindo making and selling its version of the drug.

In July 2013, AstraZeneca received a Paragraph IV notice letter from Wockhardt Limited related to Nexium, in which Wockhardt said it had filed an ANDA seeking approval to make and sell esomeprazole magnesium tablets. AstraZeneca responded by filing a patent infringement case against the company.

AstraZeneca currently has Nexium-related patent litigation in several European countries including France and Russia.

Nexium made US sales of $500 million in the third quarter of 2013. It sold $418 million in other global markets during the same period.

AstraZeneca did not respond to a request for comment.

When contacted by LSIPR, Aurobindo was unable to comment.