After reviewing the 85 publications submitted by the Burdock Group on behalf of Bayer, each of which were limited in various ways, FDA determined that there “is no credible scientific evidence to support” Bayer’s proposed health claim – even if qualified – that “vitamin D may reduce the risk of multiple sclerosis,” the agency wrote in a letter published on its website Jan. 12.
The dismissal is the second FDA dealt to Bayer related to the claim. The agency first denied Bayer’s initial petition for the proposed health claim in September 2016. Days after receiving the agency’s first missive, Bayer amended and resubmitted its petition for a more restricted qualified health claim that would did not require the same level of significant scientific agreement as a standard claim.
However, FDA argues in the most recent letter that the research submitted by the Burdock Group for this lower-level standard was still insufficient.
It explained that of 85 publications submitted by the Burdock Group as evidence, 27 were review articles that “although useful for background information … do not contain sufficient information on the individual studies” in order for FDA to draw scientific conclusions, the agency explained.
It explains that FDA must be able to review critical elements of a study, such as design, conduct and data analysis to determine if scientific conclusions can be drawn from it. Thus, interventional studies are more desirable.
However, the seven interventional studies submitted evaluated the treatment effect of vitamin D intake, rather than its effect on reducing risk of developing MS, and could not easily be transferred to prevention, FDA noted.
Given that health claims related to risk reduction rather than treatment, scientific evidence must demonstrate that the cause of the treatment effect is the same as for risk reduction in people without the disease and that the substance, in this case vitamin D, “affects these mechanisms in the same way in both diseased … and healthy people,” FDA explained.
For similar reasons, 15 of the 22 observational studies submitted for support that included individuals previously diagnosed with MS, could not be used to support the claim.
Likewise, studies that used serum vitamin D levels as a marker of vitamin D intake could not be used because while “serum vitamin D concentration is considered a good indicator of vitamin D status … it is not a valid biomarker of vitamin D intake because serum levels reflect the cumulative contributions of both exposure to sunlight and dietary intake.”
Other studies did not meet FDA’s standard because the impact of vitamin D could not be separated from potential “confounders,” such as other nutrients or food components in a supplement or food, the agency said.
For these reasons, the agency argues, “there were no intervention or observational studies from which scientific conclusions could be drawn about the relationship between the vitamin D intake and MS.” Thus, it concluded, “there is no credible evidence for a relationship between intake of the vitamin D … and reduced risk of MS.”
Based on these results, the agency could not identify a disclaimer or qualifying language that would stop the claim from misleading consumers or that would not confuse them by outright contradicting the claim.