Polymeric micelles are expected to increase the accumulation of drugs in tumor tissues utilizing the EPR effect and to incorporate various kinds of drugs into the inner core by chemical conjugation or physical entrapment with relatively high stability. The size of the micelles can be controlled within the diameter range of 20 to 100 nm, to ensure that the micelles do not pass through normal vessel walls; therefore, a reduced incidence of the side effects of the drugs may be expected due to the decreased volume of distribution. These are several anticancer agent-incorporated micelle carrier systems under clinical evaluation. Phase 1 studies of a CDDP incorporated micelle, Nc-6004, and an sN-38 incorporated micelle, NK012, are now underway. A phase 2 study of a PTX incorporated micelle, NK105, against stomach cancer is also underway.