LAUSR

Abstract Ivermectin (IVM) is a poorly water-soluble drug, which can be used for the treatment of several parasitic human infections (e.g. tropical diseases). The aim of this work was to prepare and characterize biodegradable s.c. implants, potentially enabling 6 months controlled IVM release. The implants were prepared by compressing mixtures of IVM and α-Tocopherol (TCP)-loaded microparticles based on poly-D, l -lactide or poly-e-caprolactone together with sucrose and magnesium stearate. Fifty mg implants containing 7 mg IVM were sterilized by gamma irradiation. The systems were characterized using DSC, FTIR, GPC, EPR, a crushing test, and an in vitro release tests. Results showed that implants were physically stable and they were more stable towards ionizing radiation than the corresponding microspheres. IVM release from the implants and corresponding microspheres slowed down upon irradiation in all cases. In vitro drug release from poly-D, l -lactide implants was slower than from poly-e-caprolactone implants (e.g., 25% after 2 months compared to 100% after 15 d). Mixing poly-D, l -lactide and poly-e-caprolactone based microparticles at a ratio of 1:1 (weight:weight) led to 70% IVM release after 6 months.