WASHINGTON—Thirteen-year-old guidance from the FTC confirms Bayer Corporation needed to conduct a randomized, controlled, clinical trial (RTC) to substantiate its claims that a dietary supplement defends against constipation, diarrhea, gas and bloating, according to the U.S. Justice Department.

Although all dietary supplement claims don’t need to be substantiated by an RTC, Bayer needed one to substantiate its claims in connection with its probiotic Phillips’ Colon Health “because that is what experts in the field demand for those claims," government lawyers argued Friday in court papers. Bayer failed to substantiate its claims with “competent and reliable scientific evidence", according to the 15-page reply brief filed in a New Jersey federal court.

The Justice Department alleges Bayer has violated a consent decree and should be held in contempt.

Rejecting Bayer’s argument that the government is relying on a “novel" standard, the Justice Department referenced FTC’s definition of competent and reliable scientific evidence as “tests, analyses, research, studies, or other evidence based on the expertise of professionals in the relevant area …." The Justice Department and FTC have relied on the opinion of an expert, a board-certified gastroenterologist and professor at Yale University School of Medicine. Loren Laine, the expert, has declared Bayer needed to conduct human clinical trials to substantiate its claims.

Bayer has said its probiotic claims are backed by several clinical trials on the species of bacteria in the product, in vitro and animal studies on the bacteria strains, and genomic tests that confirm the strains help protect against constipation, gas, bloating and diarrhea.

But the company has failed to contend that a human clinical trial was not possible or feasible, and the company neglected to furnish evidence that animal and in vitro studies are widely accepted substitutes for human research, said government lawyers, who relied on the 2001 FTC guidance. The Justice Department also maintains Bayer needed to conduct human clinical trials on the three specific bacteria strains in its product, and could not substantiate its claims without studying the three strains.

“Finally, it has been well known since before Bayer began marketing PCH that strain-specific evidence is necessary to substantiate efficacy claims about constipation, diarrhea, and gas and bloating for PCH," government lawyers wrote in in the brief.

The government also argued Bayer’s reliance on the Dietary Supplement and Health Education Act of 1994 (DSHEA) is misplaced.

"Whether Bayer violates the 2007 Order does not hinge on the category which the Food and Drug Administration ... places Bayer’s claims for purposes of determining compliance with DSHEA and the Federal Food, Drug, and Cosmetic Act ('FDCA')," government lawyers wrote. "Nor does the question of Bayer’s contempt depend on whether Bayer notified FDA of some claims it makes, especially given that the submission of substantiation evidence is not required (nor did Bayer provide any) and that no notice is necessary for claims Bayer makes beyond the product’s label, like those in its commercials and print advertisements."

In a final rule outlining acceptable claims for dietary supplements, FDA makes clear “that whether a claim can be marketed without going through the rigorous drug approval process is distinct from the requirement that such a claim be substantiated," the government's brief added.  

The Natural Products Association (NPA) recently expressed concern that imposing a requirement on dietary supplement firms to conduct human clinical trials would eviscerate the distinction between supplements and drugs and reduce the availability of cost-effective products. 

The government acknowledged there are cases in which human clinical trials are not required. But it pointed to FTC guidance, which says such trials are the most reliable type of evidence and delineates circumstances in which other evidence is acceptable to substantiate claims.

In a 30-page motion last month, the Justice Department asked the court to hold Bayer in contempt and assess a fine of USD $25,000 per day to coerce compliance with a 2007 order. The order, stemming from an FTC complaint involving Bayer's WeightSmart line of One-A-Day vitamins, required the company to back up any claims about dietary supplements through competent and reliable scientific evidence.

The current case, which dates back to a 2011 investigation by the FTC, is before U.S. District Judge Jose L. Linares in the U.S. District Court for the District of New Jersey, 2:07-cv-00001.