Why Did UPB Stock Pop 20% In Pre-Market Today?

The company announced positive top-line results from its Phase 2 VALIANT trial evaluating Verekitug in adults with severe asthma.
Representative image of a trending stock chart.
Representative image of a trending stock chart. (Photo: Getty Images)
Profile Image
Arnab Paul·Stocktwits
Published Feb 11, 2026   |   6:22 AM EST
Share
·
Add us onAdd us on Google

Shares of Upstream Bio Inc. (UPB) surged nearly 20% in pre-market trading on Wednesday after the company announced positive top-line results from its Phase 2 VALIANT trial evaluating Verekitug in adults with severe asthma.

Verekitug, which targets the thymic stromal lymphopoietin (TSLP) receptor, reduced annual asthma attacks by 56% with 100 mg and 39% with 400 mg compared to placebo. Patients also showed improved lung function.

Verekitug was generally well tolerated in the 478-patient study, supporting its safety profile. More than 90% of eligible participants have enrolled in the VALOUR long-term extension trial to further assess the treatment’s durability.

Read updates to this developing story on Stocktwits.

For updates and corrections, email newsroom[at]stocktwits[dot]com.

Share
·
Add us onAdd us on Google
Read about our editorial guidelines and ethics policy