KIT

Class

Anti-KIT monoclonal antibody (mast-cell depleting)

KIT, also known as CD117, is a receptor tyrosine kinase expressed on mast cells, certain blood-forming stem cells, melanocytes, and other tissues. Its natural ligand, stem cell factor, binds KIT to promote mast cell survival, growth, and activation. Mast cells are central to allergic and inflammatory disease because, once activated, they release histamine, tryptase, and other mediators that drive itching, swelling, hives, and tissue inflammation. In conditions where mast cells are excessive in number or inappropriately reactive, such as chronic urticaria (hives) or mastocytosis, reducing the mast cell population offers a way to address the disease at its source rather than only blocking the mediators after release. Anti-KIT monoclonal antibodies work by binding the receptor on mast cells and interrupting the survival signal that stem cell factor normally provides, leading to a reduction in mast cell numbers over time. This is a distinct strategy from antihistamines or mediator-blocking drugs, since it aims to reduce the cellular source rather than counteract individual chemical messengers. Because KIT signaling also matters for blood cell production, pigmentation, and other physiological processes, modulating this pathway requires attention to its effects beyond mast cells.