767 Pre-clinical and first-in-human studies of HCW9218, a bifunctional TGF-β antagonist/IL-15 protein complex, in advanced solid tumors by Peter R Rhode, Hing C Wong, Jack O Egan, Jeffrey S Miller, Manish Patel, Martin Felices, Philip M Arlen, Melissa A Geller, Pallavi Chaturvedi, Shannon Lunn, Bethany Hanke, Rose Wangen, Niraj Shrestha, Danieska Sandino, Karen L Kage, Delsy G Gaetano, Giles M Leclerc, Zhu Xiaoyun, Kelsey Mullen, Deepa Kolaseri Krishnadas