Neoadjuvant Her2-targeted Therapy and Immunotherapy with Pembrolizumab Click for Study Neoadjuvant Her2-targeted Therapy and Immunotherapy with Pembrolizumab Sponsor: Merck/Cedars-Sinai Protocol Number: 2018-04-McArthur-neoHP Start Date: 11/15/2019 Active, projected trial end date 10/2024