Development of a Solid Supersaturable Micelle of Revaprazan for Improved Dissolution and Oral Bioavailability Using Box-Behnken Design

Purpose: To enhance the oral bioavailability of revaprazan (RVP), a novel solid, supersaturable micelle (SSuM) was developed. Methods: Surfactants and solid carriers were screened based on a solubility and a flowability test, respectively. Supersaturating agents, including Poloxamer 407 (P407), were screened. The SSuM was optimized using a Box-Behnken design with three independent variables, including Gelucire 44/14:Brij L4 (G44/BL4; X-1) and the amounts of Florite PS-10 (FLO; X-2) and Vivapur 105 (VP105; X-3), and three response variables, ie, dissolution efficiency at 30 min (Y-1), dissolution enhancing capacity (Y-2), and Can's index (Y-3). The solid state property was evaluated, and a dissolution test was conducted. RVP, Revanex (R), solid micelle (P407-free from the composition of SSuM), and SSuM were orally administrated to rats (RVP 20 mg equivalent/kg) for in vivo pharmacokinetic study. Results: G44 and BL4 showed great solubility, with a critical micelle concentration range of 119.2-333.0 mu g/mL. P407 had an excellent supersaturating effect. FLO and VP105 were selected as solid carriers, with a critical solidifying ratio (g/mL) of 0.30 and 0.91, respectively. With optimized values of X-1 (-0.41), X-2 (0.31), and X-3 (-0.78), RVP (200 mg)-containing SSuM consisting of G44 (253.8 mg), BL4 (106.2 mg), FLO (99.3 mg), VP105 (199.8 mg), and P407 (40 mg) was developed, resulting in Y-1 (40.3%), Y-2 (0.008), and Y-3 (12.3%). RVP existed in an amorphous state in the optimized SSuM, and the SSuM formed a nanosized dispersion in the aqueous phase, with approximately 71.7% dissolution at 2 h. The optimized SSuM improved the relative bioavailability of RVP in rats by approximately 478%, 276%, and 161% compared to raw RVP, Revanex (R), and solid micelle, respectively. Conclusion: The optimized SSuM has great potential for the development of solidified formulations of poorly water-soluble drugs with improved oral absorption.