Ona Therapeutics raised $86.6 million in a series B to advance antibody-drug conjugate (ADC) programs in advanced cancers, with its lead asset ONA-255 progressing through clinical development in treatment-resistant breast cancer. The financing signals continued investor appetite for ADCs as companies seek to scale clinical evidence and push assets toward registrational studies. In parallel, Oscotec entered a potential $665 million deal with Agios for cevidoplenib, an oral SYK inhibitor intended for immune thrombocytopenia. The agreement is built around multiple milestones plus royalties, transferring global rights and positioning cevidoplenib for a pathway tied to cancer-resistance biology. For biotech operators, these moves show that late-stage readiness and modality momentum continue to drive large, structured transactions—even as trial safety signals and regulatory expectations remain volatile.