Core Insights - NextCure, Inc. and Simcere Zaiming have initiated the dosing of the first patient in the U.S. for the Phase 1 trial of SIM0505, an antibody drug conjugate targeting advanced solid tumors [1][3] Company Overview - NextCure is a clinical-stage biopharmaceutical company focused on developing innovative cancer therapies, particularly for patients who do not respond to existing treatments [4] - Simcere Zaiming, a subsidiary of Simcere Pharmaceutical Group, is dedicated to creating groundbreaking therapies for cancer patients globally, with a strong R&D pipeline [5] Product Development - SIM0505 is designed as a novel antibody drug conjugate targeting cadherin-6 (CDH6) and includes a proprietary topoisomerase 1 inhibitor payload, aiming for broad anti-tumor activity and improved therapeutic potential [2] - The ongoing Phase 1 trial has expanded to include U.S. patients, with dose escalation currently progressing in China [2] Clinical Trial Progress - The first patient in the U.S. has been dosed at a mid-tier level where clinical responses have been observed, marking a significant milestone in the global development of SIM0505 [3][7] - The trial aims to accelerate the timeline for proof-of-concept data, expected in the first half of 2026 [7]