The present invention relates to a sustained-release formulation comprising a metastin derivative and a lactic polymer having a weight average molecular weight of about 5,000 to about 40,000 or a salt thereof. The sustained-release formulation of the present invention slowly and stably releases compound (I) or a salt thereof over a long period of time and exerts medicinal effects of compound (I) or a salt thereof over a long period of time. Furthermore, the sustained-release formulation of the present invention, which improves patient’s convenience by reducing frequency of administration, is an excellent formulation as a clinical medicine.本發明係有關一種緩釋性製劑，其包含轉移抑制素衍生物以及重量平均分子量為約5,000至約40,000之乳酸聚合物或其鹽。本發明之緩釋性製劑係長時間緩慢且安定地釋放化合物(I)或其鹽，並長時間發揮化合物(I)或其鹽之藥效。再者，本發明之緩釋性製劑係藉由降低投藥頻率而提升患者之便利性，因此係作為臨床藥物之優良製劑。
