HONG KONG – Japan's Daiichi Sankyo Co. Ltd. has moved its HER2-targeting antibody-drug conjugate (ADC), DS-8201 ([fam-] trastuzumab deruxtecan), into a pivotal program, including a study that pits it against Roche Holding AG's Kadcyla (ado-trastuzumab emtansine, TDM-1), an ADC first approved in 2013 that's expected to hit blockbuster status this year.