INNOVATIVE DISEASE MODIFYING TREATMENTS: EVALUATING THE ATRIGEL® SYSTEM FOR ENHANCED THERAPEUTIC EFFICIENCY
DOI:
https://doi.org/10.22159/ijap.2026v18i2.56159Keywords:
Atrigel, Depot injection, Glatiramer acetate, Multiple sclerosis, Sustained-release, PLGAAbstract
Objective: This study aimed to develop and evaluate a long-acting polylactic-co-glycolic acid (PLG)-based Atrigel® system for glatiramer acetate (GA) to improve therapeutic efficiency in multiple sclerosis treatment. The formulation was optimised to form a sustained-release depot upon injection into the body, resulting in a longer delivery time and reduced frequency.
Methods: A 3² randomised complete factorial design was employed to optimise critical formulation parameters such as drug-to-polymer ratio and solvent concentration. The Atrigel® system was formulated using N-methyl pyrrolidone (NMP) and PLGA. The developed formulations were characterised for syringeability, viscosity, and in vitro drug release. Physicochemical properties were assessed, and biological evaluations included ex vivo release studies and cytotoxicity assays using the hen drumstick model and L929 fibroblasts, respectively.
Results: The optimised formulation achieved sustained drug release with reduced dosing frequency. Statistical analysis confirmed significant effects of drug-to-polymer ratio and solvent concentration on release kinetics (p<0.05). An amorphous GA dispersion was formed within PLGA, which exhibited good physical compatibility. The Higuchi model's high slope (5.3858) and negative intercept (-4.8536) corroborate the strong linear relationship between drug release and the square root of time, providing compelling evidence for classically diffusion-controlled release. Ex vivo studies demonstrated consistent release profiles (p>0.05 vs. in vitro), and cytotoxicity assays showed high biocompatibility.
Conclusion: The Atrigel® system offers a promising long-acting alternative to conventional GA therapy, with controlled release, enhanced stability, and improved patient compliance. Future studies should focus on in vivo pharmacokinetics and scalability.
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Copyright (c) 2026 SUSHANT ISHWAR POTE, OM SAMBHAJI SHELKE, RAJESH KHATHURIYA, VRUSHALI A. KULKARNI, SACHIN J. FARTADE
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