Much Ado About Nothing: Cosmetics Testing with a Placebo

By: Johann W. Wiechers, PhD, JW Solutions

Posted: February 23, 2009

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People insist on testing against a placebo, which raises another interesting issue: What should the tester do if there is no active ingredient in the formulation? Is everything active because the formulation has an effect? Is isopropyl myristate or mineral oil an active if it helps to moisturize the skin even though activity is not claimed? What do we do if an active is incorporated in an emollient that helps to moisturize the skin and in doing so, increases the skin penetration of this active? Has the emollient now become an active? One thing is clear: such a base without actives is not without efficacy, but what is the placebo? That base will definitely have a measurable placebo effect but the way in which the company defines its placebo (i.e., designs its test) depends on their claim and nothing else.

A similar situation happened to me when I submitted an article to an academic journal. I compared two formulations with different compositions and showed that the penetration from one vehicle was significantly better than from another by changing the polarity of the oil phase in which the active was incorporated. In addition to the skin penetration results, I was able to show that more clinical efficacy could be obtained by using less of the active ingredient. The claim that I made was that I could manipulate the clinical effect by changing the polarity of the emollients and reduce the dose without losing the clinical efficacy. I thought that this would have an impact in that journal, but it was rejected because, according to the reviewers, I should have tested it against a placebo.

What the reviewers failed to realize was that I was not claiming that my active was causing the effect (I had already done that in previous clinical trials), but that the clinical efficacy of an active is regulated by its formulation. When I clarified this to the reviewer, the answer was, “In proper research, everything is tested against a placebo.” I argued that I could not test it against a placebo because every formulation was different. Testing against a placebo is completely correct if you want to show that a drug or an active is responsible for the effect. But when testing whether or not a complete formulation is effective, testing against untreated skin should be conducted. Against nothing, rien, niente, niets, nichts, diddily squat.

As always, my wife is absolutely right. I do get upset about nothing. Is the difference between dermatology and cosmetics that cosmetic testing is really much ado about nothing? Placebo means to please, but who are we pleasing? Regulatory bodies, lawyers, scientists or our customers? Indeed, too much ado about nothing.

 -Prof. Dr. Johann W. Wiechers
Technical Advisor, C&T magazine
Independent Consultant for Cosmetic Science
JW Solutions, Gasthuispolderweg 30 2807 LL Gouda, Netherlands
johann.wiechers@versatel.nl