Letter to the Editor

In my article “Clinical studies involving probiotics” appearing at pages 485–489 of the November/December 2012 edition of Gut Microbes, I address issues involving whether an investigational new drug application (“IND”) is required before a clinical study of a probiotic may lawfully commence.¹ On page 488 I mention that researchers, when crafting protocols and IRBs when evaluating protocols, should recognize that adherence to IND requirements should not be necessary when, among other things, foods or dietary supplements or the components of foods and supplements are investigated to establish the “safety” of a given probiotic strain or strains for use in food or as dietary ingredients. Upon reflection, I fear there is a risk that this comment may be interpreted as suggesting that no regulatory considerations attend a decision to test the safety of a probiotic for food or dietary supplement use. Any such interpretation would not be correct. Issues with respect to the “safety” testing of a food or supplement ingredient merit an article of their own, but suffice to say for purposes of this note that a clinical study on a probiotic strain for any food or dietary supplement use should not commence unless strong scientific support for safety of the desired use already exists. Even when IRB authorization and informed consent are in hand, if it appears that the applicable statutory standards for establishing the safety of the intended use as a food or dietary supplement ingredient may not be met, sponsors and/or researchers, in my view, should, before commencing the desired study, contact FDA’s Center for Food Safety and Applied Nutrition and share with appropriate agency officials and solicit their reaction to the basis for any conclusion that such testing does not present a foreseeable risk to test subjects.