ImmunityBio, Inc. announced that the U.S. Food and Drug Administration (FDA) has accepted for review ImmunityBio?s resubmission of its Biologics License Application (BLA) for N-803, a first-in-class IL-15 superagonist, plus Bacillus Calmette-Guérin (BCG) for the treatment of BCG-unresponsive non-muscle-invasive bladder cancer carcinoma in situ (CIS) with or without Ta or T1 disease, and considered it as a complete response to the FDA?s May 9, 2023 complete response letter. The FDA has set a user fee goal date (PDUFA date) of April 23, 2024. ImmunityBio?s IL-15 superagonist N-803 (also called Anktiva® and nogapendekin alfa inbakicept): The cytokine interleukin-15 (IL-15) plays a crucial role in the immune system by affecting the development, maintenance, and function of the natural killer (NK) and T cells.

N-803 is a novel investigational IL-15 superagonist complex consisting of an IL-15 mutant (IL-15N72D) bound to an IL-15 receptor a/IgG1 Fc fusion protein. Its proposed mechanism of action is direct specific stimulation of CD8+ T cells and NK cells through beta gamma T-cell receptor binding with generation of memory T-cells while avoiding T-reg stimulation. N-803 is designed to have improved pharmacokinetic properties, longer persistence in lymphoid tissues and enhanced anti-tumor activity compared to native, non-complexed IL-15 in vivo.

N-803 is currently being evaluated in adult patients in two clinical NMIBC trials. QUILT-2.005 is investigating use of N-803 in combination with BCG for patients with BCG-naïve NMIBC; QUILT-3.032 is studying N-803 in combination with BCG in patients with BCG-unresponsive NMIBC CIS and Papillary Disease. N-803 is investigational.

Safety and efficacy have not been established by any Health Authority or Agency, including the FDA.