Upstream Bio, Inc.

Verekitug Therapeutics, Inc. (Nasdaq: VREK) is a clinical-stage biopharmaceutical company focused on developing treatments for inflammatory diseases, with an initial emphasis on severe respiratory disorders. The company's website is located at www.verekitug.com.

The company's lead product candidate is verekitug, a novel monoclonal antibody that targets and inhibits the thymic stromal lymphopoietin (TSLP) receptor. Verekitug represents the only known antagonist currently in clinical development targeting the TSLP receptor, a cytokine positioned upstream of multiple signaling cascades affecting various immune-mediated diseases. The company acquired verekitug from Astellas Pharma Inc. in 2021 and has advanced the compound into separate Phase 2 trials for severe asthma, chronic rhinosinusitis with nasal polyps (CRSwNP), and chronic obstructive pulmonary disease (COPD). The company reported positive top-line results from its CRSwNP Phase 2 trial in September 2025 and from its severe asthma Phase 2 trial in February 2026, with plans to initiate Phase 3 dosing in both indications in the first quarter of 2027. A Phase 2 COPD trial was initiated in July 2025.

Verekitug Therapeutics is a clinical-stage company with limited operating history and has incurred significant financial losses since inception. Across five clinical trials to date, the company has treated approximately 500 participants with verekitug. The company's strategy centers on leveraging verekitug's unique mechanism of action to improve treatment options for patients with severe inflammatory diseases underserved by current standard of care. Preclinical and clinical data demonstrate that verekitug is approximately 300-fold more potent than tezepelumab, the only approved TSLP-targeting therapy, enabling extended dosing intervals of up to 24 weeks compared to tezepelumab's four-week interval.

The company operates in a market with significant unmet needs. Approximately 1.2 to 1.5 million Americans are estimated to be eligible for biologic treatments for severe asthma, while approximately 300,000 adult patients in the United States are eligible for biologics for CRSwNP. The global biologics market for severe asthma generated approximately $7.5 billion in sales in 2023 across the United States, Europe, and Japan. Beyond its initial respiratory indications, the company believes verekitug has broad potential across multiple TSLP-driven diseases spanning respiratory, dermatology, gastroenterology, nephrology, and allergy/immunology therapeutic areas.