Sustained release drug delivery systems with reduced impurities and related methods

The invention relates to a sustained release drug delivery system. In some cases, a composition comprises an active agent; at least one of sucrose acetate isobutyrate and polyorthoester; an organic solvent; and 2, 6-dimethylaniline wherein the 2, 6-dimethylaniline is present at a level of less than 500 ppm. In some cases, the composition comprises an N-oxide of the active agent at a level of less than 1% by weight based on the weight of the composition. In some cases, the composition comprises a metal present at a level of less than 5 ppm. Dosage forms and methods are also provided. 本发明涉及持续释放药物递送系统。在一些情况下，组合物包含活性药剂；乙酸异丁酸蔗糖酯和聚原酸酯中的至少一种；有机溶剂；和2,6-二甲基苯胺，其中2,6-二甲基苯胺以低于500ppm的水平存在。在一些情况下，组合物包含基于组合物重量计小于1重量％的水平的活性药剂的N-氧化物。在一些情况下，组合物包含以低于5ppm的水平存在的金属。还提供了剂型和方法。