FDA finds vitamin B6 form not legal in supplements

The Food and Drug Administration (FDA) has ruled that the vitamin B6 compound, pyridoxamine dihydrochloride, cannot be used in dietary supplements.

The decision, in response to a petition from a North Carolina-based firm called Biostratum, provoked the Washington DC-based Council for Responsible Nutrition (CRN) to issue a statement warning that a precedent could be established that could see the status of other ingredients challenged.

Biostratum and CRN have been debating the status of the ingredient via FDA petitions since at July, 2005. Biostratum is the manufacturer of a pyridoxamine-based drug called Pyridorin designed to prevent the progression of diabetic nephropathy (kidney disease).

The FDA verdict, delieved on January 12, reasoned that the ingredient was authorized for investigation as a new drug before it was ever marketed as a dietary supplement. Such situations forbid dietary supplement marketing, a fact CRN accepts, but the group said in a statement it was “disappointed” with the decision nonetheless.

The trade group said the case highlighted an ongoing area of uncertainty that contributed to the status of pyridoxamine dihydrochloride being altered.

Grandfathered?

There exists a grandfathering clause for ingredients that have been on the market for more than 15 years, but CRN said the way this list functioned “was not agreed upon”.

This 15-year period coincides with the enactment of the 1994 Dietary Supplements and Health Education Act (DSHEA), around which time much evidence was presented supporting ingredients such as pyridoxamine dihydrochloride.

“We are disappointed with FDA’s response to the recent citizen petition involving pyridoxamine that apparently views as inadequate the evidence presented by the industry, including CRN, of the previous marketing of pyridoxamine, even prior to the passage of DSHEA,” said CRN vice president of scientific and regulatory affairs, Andrew Shao PhD.

“FDA’s decision suggests that companies need to produce even more extensive evidence supporting an ingredient’s marketing as a dietary supplement, including catalog and business records from more than 15 years ago.”

Companies had to ensure that they could “substantiate that an ingredient has in fact previously been marketed as a dietary supplement.”

In a previous letter to the FDA, dated September 14, 2005, the CRN’s senior vice president of scientific and international affairs, John Hathcock, wrote that:

“Pyridoxamine is unequivocally a dietary ingredient because it is one of the three primary natural forms of vitamin B6, and it is one of the two predominant forms in animal products used as human foods.”

He noted pyridoxamine was on a CRN “gold list” of grandfathered ingredients that its marketing as a dietary ingredient was “entirely consistent with the long history of the science of this form of vitamin B6.”

At the time it said it would “gladly provide documentation of this fact”.

Among other things, pyridoxamine inhibits the formation of advanced glycation deposits.