In a media blitz that included advertising and extensive press coverage, Nutri/System did something Lilly could never do because of strict federal laws prohibiting manufacturers from making off-label claims about prescription drugs. The weight-loss company, with over 500 locations in 47 states, began touting an off-label use for Prozac, at one point even suggesting that Lilly found the combination of its antidepressant and phentermine to be "very promising." Despite the view of many experts that the data supporting the "phen-Pro" combination was largely anecdotal, Nutri/System promoted its NutriRx program as a "medical breakthrough" offering "proven medications."
In a stinging letter sent in September to Nutri/System's Joseph DiBartolomeo, Ph.D., vice president for scientific affairs, Lilly officials denounced the use of Prozac in combination with phentermine for weight loss. Observing that Prozac "is not authorized for the treatment of obesity or weight control by the U.S. Food and Drug Administration," the letter accused Nutri/System of embarking "on a public campaign-including direct-to-consumer television advertising-that misrepresents the antidepressant Prozac."
Referencing statements attributed to DiBartolomeo during a Sept. 18 interview on ABC's "Good Morning America," the letter said that "Lilly has not indicated a belief that the combination of fluoxetine plus phentermine is 'very promising,' nor does Lilly have data from adequate controlled clinical trials that would characterize the combination as 'very safe' or 'something that could be very effective for people to lose weight with.'"
And in a final, more ominous warning that signaled that the dispute between the two companies has more to play out, Lilly alleged that the weight-loss company's "references to Prozac and Lilly for Nutri/System's commercial gain are violations of federal and state trademark law..." that "infringe Lilly's rights and misappropriate Lilly's good will." The letter then charged that "Nutri/System's advertising campaign creates potential public health issues and could mislead consumers."
In an interview with Psychiatric Times, DiBartolomeo, whose doctorate is in health education, nutrition and weight management, defended the off-label use of Prozac, arguing that there is no FDA prohibition against physicians using any approved drug for any purpose. He added that Nutri/System physicians prescribed the drugs only after customers met certain medical criteria.
Although he would not provide a copy of his company's protocols, calling them a "trade secret," DiBartolomeo said that individuals needed to weigh at least 20% more than their recommended body weight before receiving the drugs. In addition, he said, consumers undergo a complete physical exam and history before a physician determines the drugs are appropriate.
To support his company's use of the "phen-Pro" combination, DiBartolomeo relied on the reports of two physicians: Richard L. Atkinson, M.D., at the University of Wisconsin-Madison Medical School, and Michael Anchors, M.D., Ph.D., a Rockville, Md., family practitioner and a Georgetown University Medical School professor of medicine.
Atkinson's study, conducted several years ago, but reported in an abstract published in the March 1996 issue of FASEB Journal, involved 68 patients who took either Prozac and phentermine, or fenfluramine and phentermine over a 20-week period. The 42 patients who received Prozac lost 8.9% of their baseline body weight compared to 12.2% for the 26 individuals taking fenfluramine. Based on these results, Atkinson concluded that "in combination with phentermine, both fluoxetine and fenfluramine produce weight loss and improvement in complications of obesity, but fenfluramine is more effective."
