Inbakicept is a dimeric human IL-15 receptor alpha (IL-15 Ra) sushi domain/human IgG1 Fc fusion protein and is an IL-15 superagonist complex. Inbakicept is able to form complex N-803 (Nogapendekin alfa inbakicept) with the IL-15 antibody Nogapendekin alfa in a 1:2 ratio. N-803 mimics the function of IL-15 and amplifies anti-CD20 mAb-mediated NK cell responses and antibody-dependent cellular cytotoxicity (ADCC). N-803 also increases degranulation and IFNγ production in cells.
Inbakicept (0.01-1 nM; 20 hr) enhances human NK cell cytotoxicity and increases cytotoxic effector molecule expression[1].
Inbakicept (0.2 mg/kg; i.v.; twice weekly, for 2 weeks) enhances rituximab-directed protection from a lethal Daudi lymphoma challenge in mouse model[1].
References:
[1]. Rosario M, et al. The IL-15-Based ALT-803 Complex Enhances FcγRIIIa-Triggered NK Cell Responses and In Vivo Clearance of B Cell Lymphomas. Clin Cancer Res. 2016 Feb 1;22(3):596-608.