Stipple Bio came out of stealth with a $100 million Series A focused on advancing an ADC program and scaling its epitope-selection platform. The company’s lead asset, STP-100, is an antibody-drug conjugate designed with tumor-specific binders intended to reduce off-target toxicity—an issue that can narrow therapeutic windows across the ADC class. According to the company, STP-100 is expected to enter clinical studies in early 2027. Stipple said it plans to use the Series A cash runway to advance its Pointillist platform for identifying additional tumor-specific cell-surface epitopes and generating new Pointillist programs. The funding—described as deliberate timing to support “multiple value inflection data points”—signals investor interest in differentiating ADCs through target-engagement biology and binder engineering rather than only payload or linker changes.