US senator, NPA press FDA on NAC supplements

The Natural Products Association (NPA) has a request for FDA’s top official: Determine NAC (N-acetyl-L-cysteine) is not excluded from the definition of a dietary supplement.

Alternatively, the Washington, D.C.-based trade association requested the secretary of the U.S. Department of Health and Human Services (HHS), Xavier Becerra, issue a regulation finding NAC is lawful in supplements, following notice and comment.

The HHS secretary has authority to issue such a regulation under a provision of the Dietary Supplement Health and Education Act of 1994 (DSHEA) that has never been exercised in the 27-year history of the law.

NPA made the requests to FDA in a new citizen petition.

The 12-page document puts further pressure on FDA in response to its assertions in 2020 warning letters that NAC cannot be lawfully marketed in supplements because the ingredient was first approved as a drug in 1963.

U.S. Sen. Michael Lee (R-Utah) recently requested FDA schedule a public hearing to clarify its position on the use of the ingredient in supplements. Lee hails from Utah, a hub for the $55 billion-a-year dietary supplements industry.

“NAC has been used as an ingredient in dietary supplement products for decades, and the National Institutes of Health [NIH] Dietary Supplement Label Database identifies the use of NAC in nearly 1,500 dietary supplement products,” Lee wrote in a July 27 letter to Dr. Janet Woodcock, acting commissioner of FDA.

Consequently, FDA’s position that NAC is excluded from the definition of a dietary supplement under federal law “is of great concern to many in the dietary supplement industry who seek to provide legal and safe products to consumers and are concerned about the precedent this would set,” the senator added.

In addition to requesting a public hearing, Lee asked FDA to answer several questions related to NAC, including the specific date FDA identified the ingredient being used as both a drug and supplement in the U.S.

While Lee requested FDA answer him by Aug. 10, the agency had not responded as of Aug. 17, Brecken Denler, a staff member for the senator, said in an email.

An FDA spokesperson said the agency received the senator's letter and will respond directly to him. 

“FDA’s sudden change of policy” regarding NAC is harming stakeholders in the supplement sector, according to the citizen petition filed by Dan Fabricant, president and CEO of NPA.

“The current situation with NAC is yet another example of the inconsistent and mercurial way in which FDA chooses to both interpret DSHEA and then determines how to best use resources under DSHEA to protect the public health,” wrote Fabricant, who previously oversaw FDA’s then-Division of Dietary Supplement Programs. “Despite repeated requests from multiple stakeholders, FDA has been unable to articulate any risk to the public health posed by NAC when marketed as a dietary ingredient or dietary supplement.”

NOW Health Group Inc. CEO Jim Emme said his company has been selling NAC since October 1993—a year before Congress passed DSHEA. NOW Foods, a manufacturer and distributor of dietary supplements, is a division of NOW Health Group. 

Emme—along with Kyle Turk, NPA’s director of government affairs—met in June with several lawmakers and/or their staff on Capitol Hill. Turk said Frank McCarthy, a lobbyist, also was present during the meetings.

Emme and Turk said they met with the offices of Democratic and Republican representatives and senators from Georgia, Illinois, New Jersey, Montana, Utah and Nevada.

Since sharing their concerns with the politicians in June, Turk said the congressional offices have either met with FDA or are awaiting meetings with the agency.

Spokespersons for many of the lawmakers identified by Emme and Turk did not immediately respond to requests for comment for this article.

“Every one of these individual [congressional] offices knew the subject matter of our meetings before they agreed to meet with us,” Emme said in an interview. “We don’t want to be adversarial with the agency, but we can’t just sit on this either. Inaction is not going to solve the problem.”

NOW has sold millions—perhaps billions—of pills of NAC supplements with no adverse event reports (AERs) received, Emme shared. He added he’s not aware of other brands having received AERs related to NAC either.

Emme said he can’t understand why FDA said NAC can’t be sold as a supplement anymore after it’s been on the market in dietary supplements for about three decades.

"Why are they picking on people [who] are rule followers?" he asked. "We follow the rules. We want to work with the agency." 

According to FDA in 2020 warning letters, its conclusion is based on a provision of DSHEA that says an ingredient cannot be sold in supplements if it was first approved as a drug.

But industry sources counter plenty of examples exist in which an ingredient is sold in both supplements and drugs, like fish oil. They also have questioned whether Congress intended for the drug preclusion language in DSHEA to apply to ingredients lawfully on the market in supplements prior to passage of the law.

NPA’s citizen petition quoted an Oct. 8, 1994 Senate report published by the Committee on Labor and Human Resources, chaired by then-Sen. Orrin Hatch (R-Utah)—one of the chief architects of DSHEA. The report cited examples of ingredients in both supplements and FDA-approved drugs, including caffeine and L-carnitine.

NPA’s citizen petition was delivered Wednesday via FedEx to FDA, Fabricant said. While the agency hadn’t officially received the copy as of press time, Fabricant shared a copy in advance with Cara Welch, acting director of FDA’s Office of Dietary Supplement Programs (ODSP).

Shortly after this article was published, an FDA spokesperson said the agency has received the citizen petition submitted on behalf of NPA and would respond directly to the petitioner. 

NPA's document is the second citizen petition related to NAC in supplements. In a June 1 citizen petition, the Council for Responsible Nutrition (CRN) requested FDA reverse its position that NAC cannot be lawfully marketed in a dietary supplement.

In an interview, Fabricant said it seemed “irresponsible” for FDA to knock out an ingredient from the supplement market nearly three decades after it was first introduced in natural products.

In his estimation, “It certainly wasn’t congressional intent that if something was grandfathered, now all of a sudden the drug exclusion criteria is going to knock it out after the fact.”