Upstream Bio (UPB) TD Cowen 45th Annual Healthcare Conference summary

Key program updates and milestones

• Virecetug, a monoclonal antibody targeting the TSLP receptor, is in phase 2 for severe asthma and chronic rhinosinusitis with nasal polyps, with a COPD program starting in the second half of the year.

• Nasal polyps data will read out in the second half of this year, and severe asthma data in the second half of 2026, with a long-term extension planned.

• The company is well capitalized post-IPO, with funding to support these milestones and operations through 2027.

• All ongoing studies are powered to potentially support BLA submissions if positive, using endpoints relevant to regulators, payers, and patients.

• The team has deep experience in respiratory and immunology drug development.

Clinical data and differentiation

• Virecetug shows rapid, complete, and sustained occupancy of TSLP receptors, enabling dosing every 12 or 24 weeks.

• Phase 1 and multiple ascending dose trials demonstrated robust suppression of key biomarkers (exhaled nitric oxide, blood eosinophils) and a clean safety profile.

• Early data suggest greater potency and efficacy compared to Tezspire, with a modeled Emax of 43.4% FeNO reduction versus Tezspire's 28%.

• Modeling predicts 100 mg every 12 weeks or 400 mg every 24 weeks maintains efficacy over 48 weeks.

• No biomarker-based patient selection is anticipated, broadening potential eligibility.

Market opportunity and competitive landscape

• The severe asthma biologics market is underpenetrated and expected to grow at 6% annually, reaching $12B by 2032.

• Differentiated entrants can gain share by offering improved efficacy, convenience, or dosing intervals.

• Virecetug’s less frequent dosing (q12 or q24 weeks) and strong efficacy profile resonate with patients and physicians.

• COPD represents a significant unmet need and commercial opportunity, with biologics just beginning to penetrate.

• Market research indicates high interest in Virecetug’s profile if efficacy is confirmed.