Barcelona-based Ona Therapeutics closed an oversubscribed Series B totaling $86.6 million to advance next-generation antibody-drug conjugates. The financing supports clinical development for ONA-255 in advanced breast cancer and pushes ONA-389 toward first-in-human studies in colorectal cancer, with the company aiming to reach clinical proof of concept across both programs. Separately, Innovent submitted a China NMPA application for its CLDN18.2 ADC arcotatug tavatecan (IBI-343, TAK-921) based on interim Phase 3 results from G-Hope-001 in advanced gastric cancer. The submission received priority review, adding momentum for the CLDN18.2 competitive set that already includes multiple modality and ADC efforts. The duo of events spotlights how ADC developers are compressing timelines through large financing rounds while simultaneously escalating regulatory moves—often before full publication of clinical datasets.