Upstream Bio Inc (NASDAQ: UPB) is a clinical-stage biopharmaceutical company developing a monoclonal antibody therapy for inflammatory airway diseases. The company has no approved products and generates no product revenue as of the 10-K filed March 26, 2026. Its sole clinical asset is verekitug, an antibody candidate being evaluated in Phase 2 trials for chronic rhinosinusitis with nasal polyps and moderate-to-severe COPD. The company licensed rights to verekitug from Astellas, which had previously held rights from Regeneron, and Upstream Bio assumed obligations including mid-single-digit percentage royalties owed to Regeneron on future net sales of any approved product. Manufacturing rights are licensed from Lonza, carrying royalties ranging from less than one percent to a low-single-digit percentage of net sales plus annual payments. The company is headquartered in Waltham, Massachusetts, per its July 2024 lease with BXP Waltham Woods LLC. It completed its IPO in October 2024.

Revenue model

No product revenue as of the filing date. Future revenue, if any, would come from net sales of verekitug following regulatory approval, subject to royalty obligations owed to Regeneron (mid-single-digit percentage of net sales) and Lonza (less than one percent to low-single-digit percentage of net sales plus annual payments in Swiss francs).

Products and services

Verekitug: a monoclonal antibody in Phase 2 clinical trials for chronic rhinosinusitis with nasal polyps (CRSwNP) and moderate-to-severe COPD (VENTURE trial, NCT06981078, first patient dosed July 2025, targeting approximately 670 adults).

Customers and end markets

No commercial customers as of the filing. Target end markets are patients with chronic rhinosinusitis with nasal polyps and patients with moderate-to-severe COPD, including those with elevated eosinophils.

Value-chain role

Clinical-stage drug developer. Relies on third-party contract research organizations for clinical trials and on Lonza for compound manufacturing under a license agreement. Does not manufacture or sell products commercially.

Geographic exposure

Headquartered in Waltham, Massachusetts. Clinical trials are conducted at multicenter sites. Royalty obligations to Regeneron are structured on a product-by-product and country-by-country basis, indicating anticipated global commercialization, but no geographic revenue mix is disclosed.

Source: SEC 10-K, filed 2026-03-26

Industry: Pharmaceutical Preparations