A BioCentury analysis of 137 first-in-human studies highlighted antibody-drug conjugates as the modality driving a large share of early clinical activity at ASCO. The report says ADCs accounted for about 20% of first-in-human trials at the meeting, with diverse payloads, designs, and targets. The analysis also pointed to translational momentum in China, both as a source of early-stage programs and a key site for first-in-human development. U.S. biopharmas retained an edge in first-in-class clinical research in the dataset. The takeaway for the sector is that ADCs remain a dominant early pipeline engine as developers compete on target selection, linker chemistry, and tolerability to secure the next wave of registrational opportunities.