Efficient weapon for protracted warfare to malaria: A chondroitin sulfate derivates-containing injectable, ultra-long-lasting meshy-gel system.

Progress at elimination of malaria is limited by the challenges of reaching large rural population and ensuring patient adherence to adequate pharmacologic treatment. In the present study, a novel material (octadecylamine modified chondroitin sulfate) was synthesized, to fabricate a long acting release meshy gel system as an efficient weapon for protracted warfare to malaria. Ivermectin loaded meshy gels (IVM-MG) composed of different amount of phospholipids, triglyceride and modified chondroitin sulfate were formulated. They were in aqueous state with low viscosity before injection, but rapidly turned into gel state with significantly increased viscosity upon exposure to an aqueous environment after injection. In vitro study proved a sustained released effect in different releasing media. In vivo study showed no irritation at injection site and slowly drug release over a 30-day release period in rat model. Among the three IVM-MG formulations, IVM-MG-3 with the highest amount of octadecylamine modified chondroitin sulfate presented the highest viscosity increase after solution-gel transition, the least initial burst release, and the longest sustained release effect over 30 days in rat model. Furthermore, by using mathematical models, IVM-MG system could boost the efficacy of mass drug administration toward malaria elimination goals. Meshy gel systems for long-acting drug delivery have the potential to revolutionize treatment options for malaria and other diseases of which treatment adherence is essential for their efficacy.