45
Regulatory Considerations
An Advanced Notice of Proposed Rulemaking on regulating medical foods was pub-
lished in the Federal Register, 29 November 1996.6 It was withdrawn 22 April 2003,7 and the
agency has taken no action since then.8 At the present time, medical foods are regulated by
CFSAN’s Office of Nutritional Products, Labeling and Dietary Supplements.
The requirements for medical foods are more stringent than those for foods for
special dietary uses and likely will be for so-called “functional foods.” Functional foods
have extraneous but supposedly beneficial ingredients added (e.g., gingko, kava kava or
ginseng). There is currently no official definition for functional foods. In contrast, medical
foods must be specially formulated and processed for the partial or exclusive feeding of
a patient by means of oral intake or enteral tube feeding. They must provide nutritional
support scientifically modified for the management of the unique nutrient needs that
result from a specific disease or condition, as determined by medical evaluation, and be
used only under medical supervision. They are intended only for a patient receiving active
and ongoing medical supervision wherein the patient requires medical care on a recurring
basis and instructions on the use of the medical food.
Medical foods must contain ingredients that have GRAS (Generally Recognized as
Safe) status. GRAS is a strict safety standard set forth by FDA, requiring technical dem-
onstration of nontoxicity and safety. The list of such ingredients can be found in Title 21
of the Code of Federal Regulations for Food and Drugs, Parts 182, 184 and 186. Medical
foods also must be manufactured according to current Good Manufacturing Practices
for foods (21 CFR Part 110) and the agency regulates compliance by performing regular
inspections of manufacturing facilities. Unlike dietary supplements, which are intended
for healthy populations, medical foods are intended to meet the specific nutritional needs
of a diseased population. There is, however, no premarket approval process involved in
the distribution of medical foods.
Recently Marketed Medical Foods
Limbrel, a recently marketed medical food, will be of interest to regulatory profession-
als. According to the manufacturer, it is the first prescription product developed to safely
meet the nutritional requirements of patients with osteoarthritis. It is indicated to manage
the metabolic processes of that disease and will be sold in pharmacies only by prescrip-
tion.9 Unlike most medical food products, which are packaged as dry powders that may
reconstituted into liquids or sterile liquid solutions, Limbrel is supplied in 250 and 500
mg capsules. Limbrel consists of a proprietary blend of two types of polyphenols, which
are Free-B-Ring flavonoids and flavans, from Scutellaria baicalensis and Acacia catechu.
Flavonoids are a group of phytochemical compounds found in all vascular plants includ-
ing fruits and vegetables. They act by blocking the effects of arachidonic acid and its
conversion to inflammatory products (i.e., prostaglandins, leukotrienes and thrombox-
anes), which directly degrade cartilage. In essence, Limbrel has a mechanism of action
somewhat akin to traditional nonsteroidal anti-inflammatory drugs that inhibit isoforms
of the enzyme cyclooxygenase responsible for the first step in converting arachidonic acid
into a variety of prostaglandins, thromboxanes, and leukotrienes.10
Conclusion
There have been no regulations issued for medical foods despite the Medical Foods Task
Force Report issued in 1992 and a Medical Foods Information Sheet from the Office of
Special Nutritionals published in May 1997. The latter stated that the number and types of
foods marketed as medical foods is increasing, and while FDA is working to more clearly
define and regulate medical foods, specific requirements for their safety and appropriate
use have not yet been established. The information sheet also noted that the agency was
Medical Foods
Regulatory Considerations
An Advanced Notice of Proposed Rulemaking on regulating medical foods was pub-
lished in the Federal Register, 29 November 1996.6 It was withdrawn 22 April 2003,7 and the
agency has taken no action since then.8 At the present time, medical foods are regulated by
CFSAN’s Office of Nutritional Products, Labeling and Dietary Supplements.
The requirements for medical foods are more stringent than those for foods for
special dietary uses and likely will be for so-called “functional foods.” Functional foods
have extraneous but supposedly beneficial ingredients added (e.g., gingko, kava kava or
ginseng). There is currently no official definition for functional foods. In contrast, medical
foods must be specially formulated and processed for the partial or exclusive feeding of
a patient by means of oral intake or enteral tube feeding. They must provide nutritional
support scientifically modified for the management of the unique nutrient needs that
result from a specific disease or condition, as determined by medical evaluation, and be
used only under medical supervision. They are intended only for a patient receiving active
and ongoing medical supervision wherein the patient requires medical care on a recurring
basis and instructions on the use of the medical food.
Medical foods must contain ingredients that have GRAS (Generally Recognized as
Safe) status. GRAS is a strict safety standard set forth by FDA, requiring technical dem-
onstration of nontoxicity and safety. The list of such ingredients can be found in Title 21
of the Code of Federal Regulations for Food and Drugs, Parts 182, 184 and 186. Medical
foods also must be manufactured according to current Good Manufacturing Practices
for foods (21 CFR Part 110) and the agency regulates compliance by performing regular
inspections of manufacturing facilities. Unlike dietary supplements, which are intended
for healthy populations, medical foods are intended to meet the specific nutritional needs
of a diseased population. There is, however, no premarket approval process involved in
the distribution of medical foods.
Recently Marketed Medical Foods
Limbrel, a recently marketed medical food, will be of interest to regulatory profession-
als. According to the manufacturer, it is the first prescription product developed to safely
meet the nutritional requirements of patients with osteoarthritis. It is indicated to manage
the metabolic processes of that disease and will be sold in pharmacies only by prescrip-
tion.9 Unlike most medical food products, which are packaged as dry powders that may
reconstituted into liquids or sterile liquid solutions, Limbrel is supplied in 250 and 500
mg capsules. Limbrel consists of a proprietary blend of two types of polyphenols, which
are Free-B-Ring flavonoids and flavans, from Scutellaria baicalensis and Acacia catechu.
Flavonoids are a group of phytochemical compounds found in all vascular plants includ-
ing fruits and vegetables. They act by blocking the effects of arachidonic acid and its
conversion to inflammatory products (i.e., prostaglandins, leukotrienes and thrombox-
anes), which directly degrade cartilage. In essence, Limbrel has a mechanism of action
somewhat akin to traditional nonsteroidal anti-inflammatory drugs that inhibit isoforms
of the enzyme cyclooxygenase responsible for the first step in converting arachidonic acid
into a variety of prostaglandins, thromboxanes, and leukotrienes.10
Conclusion
There have been no regulations issued for medical foods despite the Medical Foods Task
Force Report issued in 1992 and a Medical Foods Information Sheet from the Office of
Special Nutritionals published in May 1997. The latter stated that the number and types of
foods marketed as medical foods is increasing, and while FDA is working to more clearly
define and regulate medical foods, specific requirements for their safety and appropriate
use have not yet been established. The information sheet also noted that the agency was
Medical Foods