P10.139 Interest in Gamma-cyclodextrin in the formula of a hair-loss lotion: evaluation by sensory metrology

I. Bacle¹, S. Meges¹, P. Lefrançois², JJ. Voisard², M. Luspot², S. Chesnoy³, M. Delaunois³,  P. Morinet¹

1 Institut de Recherche Pierre Fabre, France, 2 Pierre Fabre Dermatologie, France, 3 Pierre Fabre Dermo-Cosmétique, France.

Introduction/Objectives: The minoxidil-based lotions are intended for use against moderate androgenetic alopecia in adults to stabilize hair loss and encourage growth. For successful long-term use, their organoleptic qualities are an essential factor. It is thus important to offer the patients products pleasant to use on the cosmetic level, respecting the dosages, and guaranteeing improved effectiveness.

Our study aims to determine the characteristics of 4 anti-hair-loss solutions by "sensory metrology" based on the comparative evaluation of descriptors relevant for medications intended to treat the same disorders.

Physicochemistry of gamma-cyclodextrin: Gamma-cyclodextrin is obtained by enzymatic degradation of starch and occurs as cyclic octamers of glucose. Its amphiphilic character greatly enhances the solubility of Minoxidil in water. This i) strongly decreases the requirement for propylene glycol (PG) usually used to dissolve Minoxidil and ii) should therefore reduce the greasiness and stickiness of solutions.

Material and Methods: The products were: 1) Vehicle ALOPEXY 2 % ® without gamma-cyclodextrin versus vehicle ALOPEXY 2 % ® with gamma-cyclodextrin and 2) ALOPEXY 2%® with gamma-cyclodextrin versus reference (ALOSTIL 2%®). The 12 healthy female volunteer subjects satisfied the inclusion criteria. A monocentric, randomised, double blind, half-head, contra-lateral, phase-four test on the scalp study was carried out without individual profit.  The subjects received 1 ml of solution on each half-head, applied by the "expert" hairdresser. The sensory descriptors defined (1) on application on the scalp and (2) during hairstyling after 2 minutes of drying are: wet appearance and oily and sticky to the touch. Analogical non structured scales were used with software to evaluate intensity. Statistical analysis compared means two by two for each descriptor with a threshold of 5 %. Presentation was in sensory profile of two anti-hair-loss lotions. Student's paired series or Wilcoxon's tests were used (S.A.S. software).

Results: 1) The formula with gamma-cyclodextrin causes significantly less 'wetting', is less oily and less sticky than the one without gamma-cyclodextrin and 2) is less 'wetting', less oily and less sticky than the reference.

Conclusion: The ALOPEXY 2%® anti-hair-loss lotion with gamma-cyclodextrin presents a cosmetic level which constitutes an unquestionable advantage for the patient using long-term treatment.