Human bioavailability and pharmacokinetic profile of different formulations delivering alpha lipoic acid

Alpha-lipoic acid (ALA) is an important micronutrient with several pharmacologic as well as antioxidant properties. Oral formulations present problems due to characteristics of the molecule and of the pharmaceutical forms. It is known that ALA is poorly soluble; therefore to increase the solubility was reticulated in an amphiphilic matrix like lecithin. The goal of the present study was to characterize the bioavailability of new formulation and to compare the human pharmacokinetics profiles of two different pharmaceutical form: tablets and soft gel capsules following single oral administration of a ALA 600 mg. Blood samples were collected up to 8 h post dosing, and plasma á-lipoic acid concentrations were determined by Liquid Chromatography Mass Spectrometry (LC/MS/MS) detection. The results revealed that after rapid dissolution there is a good solubilisation by lecithin and that the two formulations show the same human pharmacokinetic profile. Tablet formulation is more versatile than soft capsules because it makes it possible to administer 600 mg of ALA with good compliance. The properties of the new formulation ensure rapid release in vivo and good bioavailability with high ALA content per unit dose and excellent homogeneity of release.