ELVN-002 With Trastuzumab +/- Chemotherapy in HER2+ Solid Tumors, Colorectal and Breast Cancer

Parts 1 and 3 of this study are designed to evaluate preliminary safety, tolerability, and pharmacokinetics (PK) of ELVN-002 in combination with trastuzumab in participants with advanced stage HER2 positive solid tumors. In addition, Part 3 will evaluate the preliminary efficacy of ELVN-002 in combination with trastuzumab in participants with advanced-stage HER2-positive solid tumors. Part 2 of this study will evaluate the preliminary safety, tolerability, and PK of ELVN-002 in combination with trastuzumab and chemotherapy; capecitabine and oxaliplatin(CAPEOX) or 5-fluorouracil (5-FU), leucovorin (LCV) and oxaliplatin (mFOLFOX6) in participants with advanced stage HER2 positive colorectal cancer, or eribulin or capecitabine in participants with advanced-stage HER2-positive breast cancer, or paclitaxel in participants with advanced stage solid tumors. In part 4, the preliminary safety, tolerability, PK, and efficacy of ELVN-002 in combination with trastuzumab and CAPEOX or mFOLFOX6 will be evaluated in participants with HER2-positive colorectal cancer.