PRODUCT PURITY AND POTENCY
Part of FIAR's mission will be to evaluate the products to be used in clinical studies. There are two essential features that characterize dietary suppelements: purity and potency.
PURITY
Purity is a pretty straightforward concept. The product should not have contaminants. In terms of substances like vitamins, minerals and amino acids, this is also fairly easy to evaluate. General good manufacturing practices assure that all consumed items have a certain level of purity (but see below).
With regard to botanical products (herbs), the situation can be a little more complex. Sometimes herbs are manufactured in other countries where quality control standards may not be as stringent. Evaluating these and any dietary supplements for their content of any yeast, mold, fungi, insect parts, heavy metals or other potential contaminants will be a first priority.
Broadly speaking, products may be contaminated by microbes (bacteria like E. coli, for example) or toxins. Toxins can include heavy metals, pesticides and other potentially poisonous or carcinogenic substances.
One political problem is the fact that the FDA still is sitting on comprehensive rulemaking for Good Manufacturing Practices (GMP) that specifically addresses dietary supplements. This is a very comprehensive set of rules that could go a long way to assuring public safety. One problem with it (aside from the fact it has not been adopted), is that there is no mechanism identified for establishing routine testing of dietary supplements. There are no comprehensive guidelines for maintaining purity and potency of dietary supplements and no measured set of responses for companies that fail these tests (based on how badly they might fail the test and/or how often). This is one reason that FIAR has as part of its mission the evaluation of products' purity and potency.
POTENCY
As noted in the background, FIAR will also evaluate the potency of any products that will be studied in clinical trials. For example, the amino acid N-acetylcysteine (NAC) is in widespread use by people living with HIV. In the case of NAC, it is a relatively simple matter to evaluate whether the one constituent is indeed the reduced form of the amino acid. Unscrupulous vendors may sell products which contain very little of the advertised substance. However, even reliable vendors may have product that has deteriorated in quality (for example, NAC tends to oxidize). An acceptable range for some oxidation will be determined.
In the case of botanical products, again, it's a bit more complex. Many herbs have a "signature" of certain marker compound(s), identifiable by laboratory techniques such as high-performance liquid chromatography (HPLC). Such techniques are used first and foremost to help assure accurate identification of botanical herbs. In addition, they may help to identify the strength of the herb in terms of how much of certain "active" ingredients may be present.
Botanical products can vary in the profile of chemicals that they contain, depending on the season, the time of year they are picked, if they are "wildcrafted" (i.e., picked in the wild as opposed to cultivated plants), what the soil, sun, water and nourishment conditions are like, among other variables. This variability is sometimes minimized by "standardizing" herbs to assure minimum levels of certain constituent chemicals.
One example is the silymarin compounds found in milk thistle (Silybum marianum). Silymarin actually refers to several different compounds (silybin, silydianin and silychristin are among the best recognized). These appear to be the "active" ingredients to the extent that they have been to shown to have activity in protecting the liver. Other marker compounds may serve more to assure that the herb has been identified correctly and might not reflect the herb's activity in the body.
St. John's wort is an example where the often used hypericin compound does underscore that the herb is indeed St. John's wort. However, it appears that the anti-depressant activity is at least partially related to the presence of hyperforat. Thus, standardization may serve as a rough guide to the quality and identity of the product in question, but it may not reflect the balance of ingredients that, together, may have the desired benefit.
Please stay tuned for further updates to this page.
Based on funding availability, a sample from two or three batches from selected companies will be evaluated.
 Aquilegia rockii |
OTHER ISSUES
In selecting products for clinical evaluation, there are other issues that will be considered. For example, is the product made for easy digestion? Some products can be too dense, requiring sometimes heroic efforts by the digestive tract to break the pill down. Given the problems many people with HIV confront with digestive problems, it doesn't help if most of the intervention being tested winds up in the toilet.
FIAR will also consider the source: is the company a professional company that manufactures its own products? Or are they a contract manufacturer, obtaining the best price for ingredients? Either type of company has examples of good manufacturing practices and some will also be members of the National Nutritional Foods Association (NNFA) which can further enhance the likelihood of a quality product. The NNFA is an industry group that certifies manufacturers as adhering to GMP practices. However, given the lax approach FDA has adopted regarding passage of GMP rulemaking, it makes it all that much more imperative that FIAR select good companies--and then have samples of their products tested by professional, independent labs for purity and potency.
Finally, FIAR hopes to be able to fund studies in developing nations as the organization grows. Such studies, as all studies, will require first every consideration for assuring patient safety and truly informed consent. In researching botanicals, indigenous rights of local communities will be respected. Organizations that supply herbs will be required to assure that either they are a local organization so funds return to the community or that acceptable agreements are reached between a non-local company and community members. The first principle of FIAR is to listen to what local communities feel is most appropriate in terms of what needs to be studied as well as assuring that results are locally and globally disseminated.
FIAR, a 501(c)(3) not-for-profit, does not accept pharmaceutical or nutriceutical industry funding and relies upon your generosity to continue its efforts.
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