Generic competition to Pfizer’s osteoarthritis drug Celebrex will come sooner than expected in the US after a key patent was overturned in the courts.
Several generic pharma companies have been planning to launch copycat versions of Celebrex (celecoxib) in the US on May 30, when the basic patent on the active ingredient of the drug expires.
Last March, however, Pfizer was awarded an additional 18 months of market exclusivity for the blockbuster brand – extending through December 2015 – after a method-of-use patent previously quashed in 2008 was reinstated.
Armed with the so-called ‘re-issue’ patent Pfizer filed suit against the generic drugmakers – which include Teva, Mylan, Watson Labs, Lupin Pharma and Apotex – and the case was due to be heard in court from March 19.
Now, a federal court has invalidated the re-issue patent, clearing the way for the generic launches to proceed as planned. Pfizer said in a statement that it strongly disagreed with the decision and plans to pursue “all available remedies,” including an immediate appeal.
Celebrex sales were a little over $2.9bn last year, with $1.9bn of that total coming from the US market. The drug is the company’s fourth biggest seller, and analysts have predicted the early onset of generic competition could wipe around $1bn off sales this year.
Pfizer’s recently-issued financial guidance for 2014 is based on a full year of Celebrex sales, according to chief financial officer Frank D’Amelio. The company had said it expected to record sales of between $49.2bn and $51.2bn this year, shy of the $51.6bn it recorded in 2013.
The early onset of generic competition to Celebrex comes after a torrid time for Pfizer in terms of patent losses, with cholesterol lowerer Lipitor (atorvastatin), gastrointestinal medicine Protonix (pantoprazole), Viagra (sildenafil) for erectile dysfunction and antipsychotic Geodon (ziprasidone) all going in the last two to three years.
In PMLiVE’s Top Pharma List, which ranks pharma companies by global sales, Pfizer retained the top spot, although the lead over Novartis was significantly cut.