863 In vitro and in vivo studies establish DuoBody®-CD3xB7H4 as a novel drug candidate for the treatment of solid cancers by Kate Sasser, Esther Breij, Mischa Houtkamp, Stefanie De Poot, Louise Koopman, Laura Smits-de Vries, Frederikke Lihme Egerod, Sebastiaan Wubben, Madelon Paauwe, Edward van den Brink, Andrea Gorlani, Dennis Verzijl