The US Food and Drug Administration (FDA) has released yet another Warning Letter issued to a manufacturer of a "medical food," the fourth such warning issued by the agency in the last 9 months.

Background

Under the Orphan Drug Act of 1984, medical foods are defined as "a food which is formulated to be consumed or administered enterally under the supervision of a physician and which is intended for the specific dietary management of a disease or condition for which distinctive nutritional requirements, based on recognized scientific principles, are established by medical evaluation."

Key in that definition are four points:

• The food must be consumed orally.
• It must be specifically formulated (as opposed to a naturally occurring product).
• The food must be used under medical supervision.
• The food must be intended to manage/treat a specific disease or condition.

Medical foods are not products intended to be consumed as part of an overall diet intended to reduce the risk of disease, such as eating a diet high in vegetables and fruits to help reduce the risk or effects of diabetes or obesity.

In August 2013, FDA released a new draft guidance document, Frequently Asked Questions About Medical Foods, Second Edition, which adds a fifth definitional component on the definition of "medical supervision." Per the guidance document, a medical food is "intended only for a patient receiving active and ongoing medical supervision wherein the patient requires medical care on a recurring basis for, among other things, instructions on the use of the medical food."

Notably, medical foods are also not prescribed. Per FDA, an "Rx Only" statement would cause the food to be misbranded under Section 403(a)(1) of the Federal Food, Drug and Cosmetic Act (FD&C Act).

Increasing Enforcement

Warning Letters from FDA citing medical food issues are relatively uncommon, with the agency issuing just 13 letters since 2001. But a steady drumbeat of letters sent to medical food companies indicates that FDA is taking a more active role in enforcing this burgeoning area. Since April 2013, FDA has issued four letters citing medical food issues. In other terms, nearly a third of all medical food-related Warning Letters ever issued by FDA have been released in the last nine months.

Those letters have cited a wide range of issues. In a recent letter to MetaGenics, the agency alleged that the company failed to meet the statutory definition of medical food under 21 CFR 101.9(j).

In particular, FDA said it was not aware of evidence that the diseases the company's products claimed to treat were treatable through the use of specific nutrients, thus causing the product to run afoul of the statutory requirements.

A similar letter was sent to Accera, Inc., in which FDA claimed the company failed to prove that Alzheimer's was a qualified disease capable of being treated with medical foods.

New Letter, Old Problems

Now, in its latest Warning Letter to NVN Therapeutics, FDA has again cited 21 CFR 101.9(k) in claiming that one of the company's products does not qualify as a medical food.

The product, known as Glucorein PCOS, is marketed as a medical food intended for dietary management of polycystic ovarian syndrome (PCOS).

Mirroring its language in the Accera and MetaGenics letters, FDA wrote that it was unable to find any evidence that patients with PCOS have any medically determined nutrient requirements.

"There are no distinctive nutritional requirements or unique nutrient needs for individuals with PCOS," FDA wrote. "In addition, although there are benefits to these patients obtaining Chlorogenic Acid and L-Cysteine in their diet, there are no established distinctive nutritional requirements or inherent needs for patients with PCOS to have these substances in their diets."

As a result of failing to meet the medical food standards, FDA said it would consider NVN's product to be a drug, causing it to be misbranded under the FD&C Act.

Warning Letter to NVN Therapeutics