Combining BCG with N-803 “results in significant complete response rates and long-term disease-free rates without significant systemic side effects,” reported lead study investigator Sam S. Chang, MD, of Vanderbilt University Medical Center. N-803 is a high affinity, interleukin 15 immunostimulatory fusion protein that promotes the proliferation and activation of natural killer cells and CD8+ T cells without binding to regulatory T cells. Its use in this phase two/three study including 83 patients with CIS and 77 with papillary NMIBC. In the CIS group, the complete response rate was 71% with a median duration of response of 23.6 months. NMIBC group had 12- and 24-month disease-free survival (DFS) rates of 57% and 48%, respectively. The median DFS was 23.6 months. In both groups, cystectomy was avoided in more than 90% of patients.