RM-1995

RM-1995 is an antibody-dye conjugate developed using Rakuten Medical's Alluminox platform. It consists of a monoclonal antibody specific for the cell-surface interleukin 2 (IL-2) receptor α-chain (CD25), conjugated to IRDye 700DX, a light-activatable dye. Upon intravenous administration and subsequent illumination with nonthermal red light at 690 nm, the drug induces targeted cell membrane disruption and death of CD25-positive regulatory T cells (Tregs) within solid tumors. This selective depletion of intratumoral Tregs is designed to alleviate local immunosuppression in the tumor microenvironment, improve the CD8+ T cell:Treg ratio, and reinvigorate effector CD8+ T-cell responses. Preclinical data suggest that combining RM-1995 photoimmunotherapy with anti–PD-1 checkpoint inhibitors may further enhance anticancer immune responses. The drug is being evaluated as monotherapy or in combination with pembrolizumab for advanced cutaneous squamous cell carcinoma and head and neck squamous cell carcinoma[3][4][6][9].