428 Interim analysis of Phase 2 results for cemiplimab in patients with metastatic basal cell carcinoma (mBCC) who progressed on or are intolerant to hedgehog inhibitors (HHIs) oleh Marcus Butler, Rogerio Neves, Lisa Licitra, Israel Lowy, Zeynep Eroglu, Karl Lewis, Leonel Hernandez-Aya, Axel Hauschild, Emmanuel Okoye, Siyu Li, Jean-Francois Baurain, Oliver Bechter, Ketty Peris, Aleksandar Sekulic, Alexander Stratigos, Lara Dunn, Anne Lynn Chang, Michael Migden, Kosalai Mohan, Ebony Coates, Emily Ruiz, Frank Seebach, David Weinreich, George Yancopoulos, Timothy Bowler, Matthew Fury