In November 2002 a district court in Birmingham, Alabama, found in favor of the four plaintiffs in the case of McClain v Metabolife International. They claimed that taking the Metabolife 356 had caused them to suffer various injuries, including strokes or heart attacks.
However the three-judge appeals court concluded that neither of the expert witnesses, Dr James O'Donnell and Dr Hashim Hakin, "utilized a reliable methodology to prove that use of Metabolife 365 actually causes strokes or heart attacks, either generally or in these plantiffs".
Both O'Donnell and Hakim based their testimonies on conclusions drawn from ephedra's classification as sympathomimetics, a family of drugs that stimulate the cardiovascular system by raising heart raise and blood pressure.
Long-term use of ephedrine can cause vasospasm (the narrowing of blood vessels) and vasculitis (inflammation or irritation of blood vessels), said O'Donnell, both of which conditions can lead to heart attacks or strokes.
He also said that the addition of any amount of caffeine to ephedrine makes it more toxic, posing an "imminent risk of death."
However the appeals court said that the value of his conclusions was diluted by repeated use of conditionals in his description of sympathomimetics' effects: for example, when you constrict blood vessels, you may raise blood pressure; if you stimulate the heart and increase the pulse, you may cause an abnormal heart rate.
It said that the experts substituted their own ipse dixit (unproved assertion) for scientific proof and did not applying the level of intellectual rigor required of an expert testifying about causation in a toxic tort case such as this.
David Fawel, counsel for the plaintiffs, told NutraIngredients-USA.com that the battle is far from over. He said that the experts testimonies at the trial have since been corroborated by new scientific evidence.
"It is almost like we are being punished for being first," he said. He plans to petition for a rehearing enbanc, that is, bringing the case before all the active judges in the circuit. If this is not granted - as indeed such petitions rarely are - he may go so far as to appeal to the Supreme Court.
However John Kavanagh, counsel for Metabolife, said: "Obviously the company is very pleased with the outcome. Metabolife believes it is the outcome that should have been reached two years ago - before it even came to trial."
He added that the science used by the FDA to support last year's ban on supplements containing ephedra in the United States was more lenient still than that used in the 2002 lawsuit, suggesting that it "may perhaps have reacted in a premature fashion in response to bad publicity".
Last week's decision does not mean the end of the affair for Metabolife, which now sells a range of non-ephedra dietary supplements that it says are safe and effective when taken as directed.
The company's former chief executive Michael Ellis has been charged with making "fictitious and fraudulent representations" to the FDA about the safety of Metabolife 365 and "corruptly endeavoring to influence, obstruct and impede proceedings" in relation to the ban.
The company has also asked a federal judge in New York to approve a multimillion dollar class action settlement with consumers in 300 personal injury lawsuits who are alleged to have suffered injuries when taking Metabolife 365. A hearing is scheduled for this month.