In vivo clinical efficacyDemonstrating an ingredient’s efficacy through in vivo studies
In vivo (or clinical) studies demonstrate the efficacy and functionality of an active ingredient, or a physico-chemical effect on the skin surface for an excipient under real conditions of use. Conducted with external partners, these studies deploy the latest technological advances in the fields of cosmetics and dietary supplements, with panels of volunteers from a variety of backgrounds, and notably, geographical areas.
The ingredient is tested at the recommended dose in a formula representative of its final application, the formula’s safety first being validated by our toxicology experts with the study of data on the materials that comprise the formula, and a tolerance test. Efficacy is either measured by a third party or qualified by the volunteer user himself, depending on the study protocol. The randomized, double-blind studies are compared to a placebo formula, i.e. without the tested ingredient or with a reference ingredient.
Expert measurement of efficacy
In an in vivo study, an expert performs biometric measurements and establishes a clinical rating of the effects. This expert may be for example a dermatologist, if the aim is to establish the effect on the surface condition of the skin or hair of a cosmetic or nutricosmetic.
For example, we measured the effect of Celtosomes™ Crithmum maritimum, a cosmetic active ingredient derived from marine biotechnologies. Formulated in an emulsion, its effect was compared to a placebo on the complexion radiance of 52 Chinese women aged between 45 and 62 and presenting a heterogeneity of skin color. The complexion radiance was defined by 3 parameters: homogeneity, luminosity and skin texture. It was scored on a scale of 0 to 9 by a trained technician before application, and 56 days after twice-daily application of the formulas. This scoring, supplemented by colorimetric analysis of photographs taken under normal and polarized light, showed a more radiant complexion with Celtosomes™ Crithmum Maritimum.
Measurement of perceived effectiveness
In vivo studies also evaluate the efficacy perceived by the volunteer user himself, or his family. The benefits, whether visible or felt, constitute the ultimate validation of efficacy. Perception can be qualitatively or quantitatively collected through a self-assessment questionnaire, or through the Quality of Life Index.
For example, we evaluated the perception of age after application of a formulation containing a cosmetic active ingredient (Aspar'Age™), in addition to measurements of the surface area of wrinkles, their number, and depth. The evaluation was carried out by 64 volunteer users with before/after photos acquired in high definition by ColorFace® and presented blind. Visible benefits were demonstrated after 28 days of use, with skin that looked younger and less wrinkled.