We compared the biodistribution of tLNPs composed of L10, which we found to be effective for transfecting MM cells in vitro, with tLNPs composed DLin‐MC3‐DMA, as it is the only ionizable lipid approved for systemic delivery of RNA.[10] Mice were injected with CAG‐Luc cells and 16 d post‐tumor inoculation were mock‐treated or treated retro‐orbitally with tLNPs loaded with fluorescently labeled siRNA coated with either an anti‐CD38 or isotype control antibody (Figure5A). The gene discussed is CD38; the disease is Miyoshi myopathy.