Patent Infringement: Sun Pharma sued by Orexo over generic opioid dependence drug Zubsolv

The lawsuit was filed in response to an Abbreviated New Drug Application ("ANDA") filed by Sun with the US Food and Drug Administration ("FDA"). Orexo claimed that in its ANDA, Sun Pharma sought to market and sell generic versions of Orexo's ZUBSOLV products, (buprenorphine and naloxone) sublingual tablets (CIII), in the US prior to the expiration of the patents listed in FDA's Orange Book. The patents have expiration dates ranging from December 2027 to September 2032.

The drug, ZUBSOLV (buprenorphine and naloxone) sublingual tablet (CIII) is indicated for the maintenance treatment of opioid use disorder and should be used as part of a comprehensive treatment plan, which includes counseling and psychosocial support. Treatment should be initiated under the direction of physicians who are certified under the Drug Addiction Treatment Act of 2000, and who have been assigned a unique identification number ("X" number).

"Since Orexo timely filed a lawsuit against Sun Pharma, USFDA is statutorily precluded from approving Sun's ANDA for 30 months, or until a district court decision finds the patents to be invalid or not infringed, whichever occurs first. The 30-month stay period began as of the date Orexo received the notice letter from Sun Pharma advising Orexo of their ANDA filing," stated a recent release by Orexo.

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Commenting on the same, Nikolaj Sørensen, Orexo's president, and CEO, said, "Today Orexo is much more well prepared to defend the exclusivity of ZUBSOLV than when we started our previous patent litigation. We successfully defended the exclusivity for ZUBSOLV® in the past and we are well prepared to do so again by enforcing our patent rights against Sun."

"Orexo expects increased legal expenses related to the litigation process, with the majority of the expenses expected in 2021 and 2022. The expenses in 2020 are expected to be non-material and any changes to OPEX guidance will be shared in quarterly reports," the release added.

Orexo commercializes its lead product ZUBSOLV for the treatment of opioid use disorder. Total net sales for 2019 amounted to SEK 844,8 million and the number of employees was 127. Orexo is listed on the Nasdaq Stockholm Mid Cap (ORX) and is available as ADRs on OTCQX (ORXOY) in the US. The head office, where research and development are also performed, is situated in Uppsala, Sweden.