UK biotechnology company Acambis said this morning it had won its dispute with Danish rival Bavarian Nordic over patents covering Modified Vaccinia Ankara (MVA), a technology underlying both firms’ smallpox vaccines.

A judge at the International Trade Commission (ITC) invalidated all of the claims lodged by Bavarian Nordic against Acambis, said the UK firm in a statement.

But in its own statement, the Danish company insisted that the ITC judge had concluded that Acambis has infringed two of its patents on MVA. It also said that it would appeal findings that the two patents are invalid, due to inconsistencies in the judge’s ruling.

Bavarian Nordic can take the matter to ITC Commissioners, who would make a final determination in the case by early December 2006, and said it “feels confident of having this decision reversed."

Meanwhile, Acambis asserted that the ITC judge “has now invalidated each of the patent claims asserted against Acambis and denied Bavarian Nordic's request for an exclusionary order. Those invalidated claims are no longer enforceable.”

Last month, Acambis published Phase II data from its latest smallpox vaccine candidate – MVA3000 - showing that it generated a fourfold increase in neutralizing antibodies against the virus in more than 75% of patients. The UK firm and US partner Baxter are vying to win a lucrative US government contract for smallpox vaccine that can be used in the 20 million Americans who cannot receive the traditional shot.

Bavarian Nordic has also filed complaints with the District Court of Delaware in the USA and the Commercial Court in Vienna, Austria.

Regarding the complaint before the District Court of Delaware, the judge has ordered the termination of Bavarian Nordic’s trade secrets claim. As with the ITC decision on the same issue, the termination was based on a question of jurisdiction, according to Acambis.

A confidential disclosure agreement, signed between Acambis and Bavarian Nordic in February 2002, contains a mandatory arbitration clause requiring any such disputes between the two companies to be settled in arbitration in Frankfurt, Germany under the rules of the International Chamber of Commerce, said the UK company.