Cambridge Antibody Technology’s share price fell by more than 5% during morning trading on the London Stock Exchange today after the firm revealed that Abbott Laboratories had won the right to appeal the ruling in a royalty dispute between the two companies.

Abbott is seeking to overturn a December 2004 verdict that ruled it was at fault for only paying CAT the minimum 2% royalty rate in their agreement on the rheumatoid arthritis drug, Humira (adalimumab), rather than 5% [[20/12/04c]]. The US firm made a written application for permission to appeal the verdict last month [[15/02/05c]].

In a statement released yesterday, the Court of Appeals said that points raised by Abbott “appear, just, to raise a real prospect of success” and that they were “sufficient in the circumstances to provide a compelling reason for an appeal.”

CAT first took Abbott to court back in October 2003 after receiving the minimum level of royalty payments for Humira [[15/10/03a]]. The UK company had argued that it should receive a full royalty, but Abbott claimed that royalties could be shared with third parties. As a result of the December ruling, CAT has already received almost $24 million dollars in royalty arrears [[31/01/05e]].