Three-month subchronic intramuscular toxicity study of rotigotine-loaded microspheres in SD rats

► Rotigotine-loaded microspheres (RoMS) is a long-acting sustained-release formulation. ► Intramuscular subchronic toxicity in rats were evaluated at 15, 45, 135 and 240 mg/kg/week. ► Major toxicological effects were related to dopamine receptor activation by rotigotine. ► Foreign body removal reaction was induced by expcipient and vehicle. ► RoMS has exhibited high safety on SD rats with NOAEL of 45 mg/kg/week.