Eifler, Nora, Rossi, Sara-1, Bitar, Malak, Tedeschi, Concetta, Be, Celine and Duvnjak, Marieta Effective methods for assessing the saturation concentration of an API in a topical formulation.

Abstract

In topical development, the characterization of the solubility of a molecule in the formulation is paramount. Fick's law of diffusion states that the permeation of a molecule through the skin depends on the concentration of the molecule in its vehicle, which is maximal at its saturated state. Accordingly, a topical drug should be ideally formulated as a suspension, where the thermodynamic activity for flux through the skin is maximal.
Unfortunately, topical suspensions - whether in a cream, gel or ointment - bear the risk to change over stability. Extensive characterization is required, making development time intensive and costly. To avoid risks and costs, companies usually prefer a physically stable formulation, where the molecule remains in solution over the entire shelf-life.
In this paper we present powerful analytical tools such as Raman, TEM and SC-XRPD to assess solubilization and crystallization properties of a topical API - CEE321 - to optimize both - thermodynamic activity for skin flux and physical stability in the formulation over shelf-life.

Item Type:	Article
Date Deposited:	07 Feb 2025 00:45
Last Modified:	07 Feb 2025 00:45
URI:	https://oak.novartis.com/id/eprint/54415