WALTHAM, Mass., April 17, 2026 (GLOBE NEWSWIRE) -- Upstream Bio, Inc.  (Nasdaq: UPB), a clinical-stage company developing treatments for inflammatory diseases, with an initial focus on severe respiratory disorders, today announced two upcoming poster presentations at the American Thoracic Society (ATS) 2026 International Conference in Orlando, FL, on Monday, May 18, 2026. The presentations feature new data from the Phase 2 VIBRANT trial evaluating verekitug, the only known antagonist to the thymic stromal lymphopoietin (TSLP) receptor currently in clinical development, in chronic rhinosinusitis with nasal polyps (CRSwNP). The data to be presented include the clinical effect of verekitug in participants with CRSwNP and comorbid asthma, as well as its impact on nasal and blood biomarkers.

Presentation details:

• Presentation Title: Verekitug, a Thymic Stromal Lymphopoietin Receptor Antagonist, Administered in Participants with Chronic Rhinosinusitis with Nasal Polyps and Comorbid Asthma in the VIBRANT Trial
  Presenting Author: Joseph K. Han, MD, Old Dominion University
  Poster Board Number: P1397
  Session: B32 – Rise of the Biologics: A New Hope for Breathing Easier
  Presentation Date and Time: Monday, May 18, 2026 – 11:30 AM – 1:15 PM ET

• Presentation Title: Verekitug, a Thymic Stromal Lymphopoietin Receptor Antagonist, in Chronic Rhinosinusitis with Nasal Polyps: Effect on Type 2 Inflammatory Biomarkers in the VIBRANT Trial
  Presenting Author: Joseph K. Han, MD, Old Dominion University
  Poster Board Number: P1398
  Session: B32 – Rise of the Biologics: A New Hope for Breathing Easier
  Presentation Date and Time: Monday, May 18, 2026 – 11:30 AM – 1:15 PM ET

About Upstream Bio
Upstream Bio is a clinical-stage biotechnology company developing treatments for inflammatory diseases, with an initial focus on severe respiratory disorders. The Company is developing verekitug, the only known antagonist currently in clinical development that targets and inhibits the receptor for thymic stromal lymphopoietin (TSLP), a cytokine which is a clinically validated driver of inflammatory response positioned upstream of multiple signaling cascades that affect a variety of immune-mediated diseases. The Company has advanced this highly potent monoclonal antibody into separate Phase 2 trials for the treatment of chronic rhinosinusitis with nasal polyps (CRSwNP), severe asthma, and chronic obstructive pulmonary disease (COPD). Upstream Bio’s team is committed to maximizing verekitug’s unique attributes to address the substantial unmet needs for patients underserved by today’s standard of care. To learn more, please visit www.upstreambio.com.

Investor and Media Contact:
Meggan Buckwell
Director, Corporate Communications and Investor Relations
ir@upstreambio.com