This story has been updated from a previous version.
NEW YORK, May 31 – Roche said Thursday it would appeal the European Patent Office’s decision to revoke Roche’s patent for a number of enzymes, including Taq DNA polymerase, a staple in conducting PCR and gene sequencing.
“We will appeal this ruling because it is incorrect,” a Roche spokeswoman said.
The Munich-based EPO’s decision found that patent EP-0-258-017 BI for broad thermostable enzymes was invalid because it was not novel and was obvious based on prior art, said Promega, one of the four companies that opposed the European patent.
The decision followed similar findings made by courts in the United States and Australia in 1999 and 1997, respectively. The US decision is currently under appeal.
Promega, along with Becton Dickinson, New England BioLabs, and BioLine, argued to the EPO that other companies had purified Taq DNA polymerase prior to Roche receiving the patent and that the recombinant Taq gene was obvious based on prior art.
Promega chairman and CEO William Linton told GenomeWeb that the EPO’s decision would now allow his company and other makers of Taq DNA polymerase, essentially the gas that drives the DNA amplification process, to sell consumables without being liable for having to pay royalties to Roche.
“This decision has broad-reaching implications for users and reaffirms once again what Promega and many others in the research community have long believed – that the Taq patents should never have been issued,” said Linton.
Linton estimated the thermostable enzyme market at an annual $150 million to $200 million.
Some of the implications of the EPO's findings remain unclear due to conflicting interpretations of what the patent covers. While Promega said that the patent referred to both native and recombinant forms of Taq DNA polymerase, Roche, which holds other patents for recombinant Taq, said the EPO decision only affected the native form.
If Roche is correct in its interpretation of the ruling, the effects of the decision will be less drastic. The Roche spokeswoman said that native Taq represents only 10 percent of its PCR reagent business, while recombinant Taq represents 90 percent of this business. Roche has 25 worldwide licensees for native Taq, 13 of which are in Europe.
" Only the native Taq patent is affected," Roche said in a statement. "Nowadays, native Taq polymerase only plays a negligible role, as 90 percent of Taq polymerase used for polymerase chain reaction are of recombinant origin. The latter is covered by other Roche patents."
Promega, which only manufactures native Taq polymerase, said that those patents were also being challenged in Europe.
Promega has not had a license for the enzyme since 1995, when a previous five-year licensing agreement with Cetus expired. In 1991, Roche bought Cetus and soonafter sued Promega in the US for breach of contract and patent infringement related to Taq polymerase. In response, Promega challenged the validity of the patent.
The patent was deemed unenforceable by a US court in 1999.
In 1994 the EPO issued a Taq patent to Roche but reopened the examination procedure several months later.
Roche still holds a patent for the PCR process, meaning that companies that make PCR-based instruments must still have a license from the Swiss pharmaceutical giant.