Development of a Capsule Formulation Containing Dry Bark Extract of Annickia Polycarpa: Laboratory to Pilot Scale-up

This study focuses on the development and scale-up of a capsule formulation based on the dry extract of Annickia polycarpa bark, a West African medicinal plant known for its antimalarial, antibacterial, and antioxidant properties. The objective was to adapt the process, initially optimized at laboratory scale, to a pilot scale for pharmaceutical valorization. Hot maceration followed by drying yielded a higher extraction rate at pilot scale (24%) compared to laboratory scale (18.46%). Powder characterization revealed very fine particles (Dx50 < 125 µm), residual moisture within pharmacopeial limits (4%), and good solubility (100-200 g/L). However, the powders exhibited poor flowability, requiring wet granulation with pregelatinized starch or carboxymethylcellulose as binders. This step significantly improved flow properties and particle cohesion. Capsules produced from the granules met uniformity of mass requirements according to the European Pharmacopeia and displayed a rapid disintegration time (< 7 minutes), ensuring efficient release of active compounds. The human equivalent dose (HED), extrapolated from animal studies, was estimated at 3,402 mg/day for a 70 kg adult, allowing the definition of capsule size 2 with 247-296 mg of extract per unit. Overall, these findings demonstrate the technical feasibility and robustness of the encapsulation process for Annickia polycarpa, providing promising perspectives for industrial development and the production of standardized phytomedicines. However, further studies on long-term stability, bioavailability, and clinical efficacy are required to ensure the quality, safety, and therapeutic effectiveness of the final product.