MDK-703

MDK-703 is an investigational biologic drug developed by Medikine. It is a fusion protein composed of an engineered peptide mimetic of human interleukin-7 (IL-7), called MDK-1472, fused to an immunoglobulin G2 (IgG2) Fc-domain[1][3]. This design results in a molecule with hematopoietic and immunopotentiating activities that emulates the effects of endogenous IL-7 on T cells, including enhancing the generation, function, and survival of memory T cells[1][3][5]. Unlike natural cytokines or previous IL-7 agents, MDK-703 is structurally unrelated to native IL-7 and engineered for low immunogenicity; it does not generate anti-drug antibodies that neutralize native IL-7[3][5]. Preclinical and early clinical data show that MDK-703 expands CD8+ and CD4+ T cell populations—especially memory subsets such as T-stem cell memory (Tscm), central memory, and effector memory cells—with minimal effect on regulatory T cells or NK cells[4][6]. The drug acts as a direct agonist at the interleukin 7 receptor by binding both subunits (IL‑7Rα and γc) to induce downstream signaling via STAT5 phosphorylation[6]. Its primary indication under investigation is oncology (solid tumors), but potential applications include anti-infective therapy, vaccine enhancement, and treatment of lymphopenia[4].

Other names

Fc fusion IL-7 mimetic MDK-703