Kyle Bass challenges second Vimovo patent

Hedge fund manager Kyle Bass has filed another petition for an inter partes review (IPR) of a patent covering Horizon Pharma’s arthritis drug Vimovo (naproxen/esomeprazole magnesium).

Like many of the drugs whose patents have been targeted by Bass, Vimovo is Horizon’s flagship product, and in 2014 generated net sales of $163 million. According to reports, the latest IPR targets US patent number 8,858,996.

Horizon acquired the rights to Vimovo from AstraZeneca in 2013.

It is the second Vimovo patent to be challenged by Bass’s Coalition for Affordable Drugs, a coalition he set up through his hedge fund Hayman Capital Management.

Last month the coalition filed a petition to review another patent covering Vimovo, US number 6,926,907. According to reports, it was the fifteenth IPR petition that the coalition has filed to date.

The ’907 patent, due to expire in 2023, is owned by pharmaceutical company Pozen and licensed to Horizon.

A spokesperson for Horizon told LSIPR: “There is nothing new or concerning in this IPR request and similar invalidity arguments have been previously presented in litigation.

“Our arguments on obviousness, patentability, and priority dates are very strong and we expect to prevail in IPR review and litigation.”                                                                                                                                                                                                                                                             Bass had not responded to a request for comment at the time of publication. LSIPR will update the story should we hear from him.