Upstream Bio, Inc. is a biotechnology company in the clinical development stage, dedicated to innovating therapies for inflammatory conditions, particularly those affecting the severe respiratory system. Its pipeline notably features verekitug, a monoclonal antibody designed to selectively target and suppress the thymic stromal lymphopoietin receptor. Beyond this, the company is actively developing treatments for severe asthma, chronic rhinosinusitis with nasal polyps, and chronic obstructive pulmonary disease.