(CN) – Vanderbilt University scientists did not contribute enough in the creation of the erectile dysfunction-fighting compound tadalafil to be called joint inventors, the Federal Circuit ruled.
The Washington, D.C.-based appellate panel upheld a district court ruling that three Vanderbilt scientists had failed to provide convincing evidence that they co-invented the active ingredient in the drug Cialis.
The scientists sued Icos Corp., which holds the two patents to which the university researchers wanted their names added.
A Glaxo France scientist is named on the patents as the sole inventor of the compound, but the Vanderbilt scientists say that their so-called “Vanderbilt Structural Features” led directly to the “identification of the GR30040x molecule,” and that the “key modification” to that molecule, which led to the discovery tadalafil, was their idea.
Glaxo sponsored some of the Vanderbilt’s research in the 1980s and 1990s, and Glaxo scientists had access to reports containing some of the university’s key discoveries around the time that Glaxo France researchers invented tadalafil, the Vanderbilt scientists argued.
Icos claimed that Glaxo France researchers discovered the compounds independently.
But where Icos was able to “point to Glaxo documents to corroborate various details of its story,” Vanderbilt “admitted in the district court that it had no direct evidence to support its view of the facts,” according to the ruling.
Writing for the panel, Judge Raymond Clevenger III found that “conception requires identification of the specific chemical structure of the compound.” The parties all agree that a Glaxo France scientist was the first to conceive of tadalafil, and “Vanderbilt failed to produce any evidence of joint invention of tadalafil.”
“For Vanderbilt to succeed in its … claim, it must carry its burden of proof of demonstrating that the Vanderbilt scientists contributed to the claimed invention with clear and convincing evidence,” Clevenger wrote. “The district court’s findings demonstrate that under the correct legal test, Vanderbilt did not carry its burden.”