PCR case ends with Roche victory

Roche claims victory in its European patent dispute over rights to Taq DNA polymerase, an enzyme used in polymerase chain reaction (PCR) testing.

The Technical Board of Appeal of the European Patent Office has upheld its patent on polymerase chain reaction (PCR) process enzymes, held by Roche Diagnostics, bringing to an end a drawn-out legal dispute over the nucleic acid testing technology used in clinical testing and drug discovery.

The TBA also ruled in Roche's favour in a dispute over the firm's PCR process patents in 2002. The latest ruling is the final determination of the EPO and cannot be appealed.

The enzyme patent covers "Thermus aquaticus" (Taq) DNA polymerase, a key tool in PCR testing, which has been at the centre of case. In 2001 the EPO revoked Roche's patent on the enzyme on the grounds that it was based on older research and was not novel. The US patent on the enzyme was revoked in 1999, but this verdict was also overturned on appeal earlier this year

The TBA upheld Roche's patent in an amended form, with claims covering a wide range of subject matters relating to Taq DNA polymerase (e.g. native and recombinant full-length Taq DNA polymerase, DNA encoding full-length or truncated Taq DNA polymerase, composition comprising Taq DNA polymerase and one or more non-ionic detergents).

Both the US and European actions were brought by Promega, a US-based laboratory supply company, with support from Becton Dickinson, Bioline and New England Biolabs.

The situation is still not resolved in the US, however. The appeals court has reversed one patentability issue that had been quashed by the lower court - the enzyme's molecular weight - but refused to affirm on two other grounds and remanded them to the lower court for further deliberation.

Meanwhile, Roche recently gave a firm sign of its confidence in the legal status of Taq DNA polymerase by starting construction of a €133 million production plant for PCR reagents in the US. However, it is now facing a fresh legal challenge from Applera, a reseller of its PCR technologies.

It has been suggested that Roche's newly-affirmed intellectual property position in the enzyme may lead to price increases and a higher royalty rate from resellers.