23andMe Holding Co. announced the U.S. Food and Drug Administration (FDA) has cleared the investigational new drug application for 23ME-01473 (?1473), a natural killer (NK) cell activator intended to treat cancer. 23andMe plans to evaluate ?1473 in participants with advanced solid tumors in a Phase 1 clinical study beginning in the first half of 2024.

?1473 targets ULBP6 to restore anti-tumor immunity through NK and T cells. ULBPs are stress-induced ligands found on the surface of cancer cells that bind to their receptor, NKG2D, on NK and T cells. Cancers escape immune cell recognition by shedding ULBP ligands from their cell surface, which act as immunosuppressive molecular decoys.

Blocking the binding of soluble ULBP6 to NKG2D may restore immune cell recognition and killing of cancers. Further, ?1473 is Fc-effector enhanced, which provides an additional mechanism for NK cells to induce cell death of ULBP6-expressing cancer cells. '1473 also has the potential to address a major unmet need in cancer treatment: patients who may have or may develop tumor resistance to checkpoint inhibitors.

By combining NK and T cell activation, '1473 may initiate a broader and deeper response of the immune system to kill cancer cells, and delay tumor resistance seen in treatment with traditional checkpoint inhibitors.