The invention relates to iRNA agents, which preferably include a monomer in which the ribose moiety has been replaced by a moiety other than ribose that further includes a tether having one or more linking groups, in which at least one of the linking groups is a cleavable linking group. The tether in turn can be connected to a selected moiety, e.g., a ligand, e.g., a targeting or delivery moiety, or a moiety which alters a physical property. The cleavable linking group is one which is sufficiently stable outside the cell such that it allows targeting of a therapeutically beneficial amount of an iRNA agent (e.g., a single stranded or double stranded iRNA agent), coupled by way of the cleavable linking group to a targeting agent—to targets cells, but which upon entry into a target cell is cleaved to release the iRNA agent from the targeting agent.
本发明涉及iRNA代理,它们包括一个单体,其中
核糖基团已被替换为其他
核糖基团,进一步包括一个具有一个或多个连接基团的连接体,其中至少一个连接基团是可裂解的连接基团。 连接体反过来可以连接到所选的基团,例如
配体,例如靶向或递送基团,或改变物理性质的基团。 可裂解的连接基团足够稳定,使其允许将治疗上有益的iRNA代理(例如单链或双链iRNA代理)通过可裂解的连接基团耦合到靶向剂,以靶向细胞,但进入目标细胞后会裂解以释放iRNA代理。