The U.S. Supreme Court has rejected a request by GlaxoSmithKline (GSK) to review an appeals court ruling allowing Apotex to market a generic version of GSK's antidepressant Paxil.

GSK appealed a decision by the U.S. Circuit Court of Appeals that ruled that GSK's patent on Paxil (paroxetine HCl) was invalid because another company discovered the drug accidentally several years earlier. In May, the Department of Justice filed a brief advising the court not to hear the case. "As the court of appeals correctly held, petitioners are not entitled to such a patent," U.S. Solicitor General Paul Clement said in the brief.

A spokeswoman for GSK said the company was disappointed with the Supreme Court's decision. While GSK would not have gained financially from a Supreme Court review as generic Paxil is already on the market, "We felt like it was an important issue to be considered," she said.

Richard Samp, chief counsel for the Washington Legal Foundation (WLF), said the decision would cause a "net decrease in research and development expenditures for new lifesaving therapies."

WLF said the appeals court's ruling "invalidated a significant pharmaceutical patent based on a finding that the drug was not 'novel' when the patent application was filed in 1986 -- even though it is undisputed that if the drug existed before then, it was in such minute quantities as to be undetectable." WLF also said that "by invalidating a major patent based on a position that conflicts with long-settled patent law precedents, the Federal Circuit is saying it is unwilling to uphold intellectual property rights in the face of public demands for lower drug prices."

The case is SmithKline Beecham v. Apotex, No. 05-489. (http://www.fdanews.com/did/5_120/)