Exelixis takes Cipla to court over generic cancer drug
Cipla claims Cabometyx patents are invalid | Exelixis wants generic blocked until at least 2030.
US biotech firm Exelixis is heading to court with Indian pharma giant Cipla in its latest battle to protect patents covering cancer treatment Cabometyx.
The California-based firm filed a complaint at Delaware District Court on March 16 alleging patent infringement arising from Cipla’s intention to manufacture and sell a generic version of Cabometyx before five patents covering the drug expire.
Cabometyx (cabozantinib) is a tyrosine kinase inhibitor (TKI) approved by the US Food and Drug Administration (FDA) to treat patients with advanced kidney and liver cancer.
The patents-in-suit that Exelixis says will be infringed by Cipla’s Abbreviated New Drug Application (ANDA) are US numbers 8,877,776, 11,091,439, 11,091,440, 11,098,015, and 11,298,349. Four of the patents are due to expire in 2030 and one in 2032.
On February 2 this year, Cipla notified Exelixis that it had submitted an ANDA to the FDA for a generic version of Cabometyx. It alleged that the patents-in-suit are “invalid, unenforceable, and/or will not be infringed by the commercial manufacture, use, importation, offer for sale, or sale of the drug product described in Cipla’s ANDA”. Cipla confirmed its intention to sell its product before the expiration of Exelixis’ patents.
Exelixis is asking the court to enforce the validity of its patents and order that any effective FDA approval for Cipla’s ANDA should not be earlier than the date the patents expire. The firm is being represented by Morris, Nichols, Arsht & Tunnell.
Patent challenges
In January this year, Exelixis scored a win against rival MSN Laboratories as the Delaware District Court rejected MSN’s challenge to its cabozantinib compound patent (US number 7,579,473). This judgment will potentially block US regulatory approval of MSN’s generic until the patent expires in 2026.
However, the court said that MSN’s proposed ANDA did not infringe another of Exelixis’ patents.
Commenting on the decision, executive VP, general counsel and secretary at Exelixis, Jeffrey Hessekiel, said: “We are pleased the court upheld the validity of Exelixis’ cabozantinib compound patent.
“While we are disappointed with the court’s decision concerning infringement of the ’776 patent, we remain confident in the strength of the cabozantinib patent estate. We will continue to vigorously defend our intellectual property, safeguarding the scientific innovation that drives Exelixis’ ability to continue to discover, develop and ultimately bring new medicines to patients with difficult-to-treat cancers.”
Exelixis and MSN will however head back to court in October over alleged infringement of four different patents, also named in the suit with Cipla.
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