Alomfilimab (KY-1044) is a humanized monoclonal antibody targeting the inducible co-stimulator receptor (ICOS). As a selective ICOS blockade, it manipulates ICOS expression heterogeneity on T-cell subtypes. It can be used to study tumors.

ICOS (Rat):0.48 nM (EC50), ICOS (MONKEY):0.22 nM (EC50), ICOS (mouse):0.53 nM (EC50)

Alomfilimab is a whole-human IgG1 antibody against inducible costimulatory receptors (ICOS). Alomfilimab binds ICOS of different species (human, crab-eating monkey, rat, and mouse) with similar affinity (aKd < 3 nmol/L). Alomfilimab significantly induced luciferase signal (EC50 was 0.15 nmol/L). Similar EC50 was obtained for mouse ICOS (0.53 nmol/L), rat ICOS (0.48 nmol/L) or cynomophage monkey ICOS (0.22 nmol/L). [1]

Alomfilimab (10 mg/kg; Intraperitoneal injection; Twice a week; Lasting 3 weeks) mIgG2a monotherapy blocks tumor growth in lymphoma/myeloma tumor models.
Alomfilimab mIgG2a preferently depleted ICOS-high Treg cells and improved the ratio of CD8+ TEff to Treg cells in TME.
Pharmacodynamic effects of Alomfilimab hIgG1 in NHP with weekly repeated intravenous doses of 0, 10, 30, and 100 mg/kg for 4 weeks (5 doses). Exposure and full occupancy of ICOS on circulating CD4+ T cells remained unchanged at all doses. [1]