MR1-1

MR1-1 is a recombinant immunotoxin designed to target the tumor-specific antigen EGFRvIII, which is commonly expressed in glioblastoma multiforme (GBM). It consists of an antibody fragment that specifically binds to EGFRvIII fused to a toxin moiety, enabling selective cytotoxicity against tumor cells expressing this antigen. The drug has been studied for direct delivery into the brain using convection-enhanced delivery (CED) to bypass the blood-brain barrier. Preclinical studies have demonstrated its safety and potential efficacy in animal models of GBM[4]. There are also references suggesting use of "MR1-1" as a synthetic peptide or conotoxin targeting neuronal acetylcholine receptors (nAChR α9/α10), but these refer specifically to "Mr1.1" or "alpha-conotoxin Mr1.1," which is distinct from the immunotoxin MR1-1 described here[5][3][4].