Upstream Bio (UPB) investor relations material

Company positioning and lead asset

• Focused on developing verekitug, a monoclonal antibody targeting the TSLP receptor, aiming for best-in-class efficacy and quarterly dosing in severe asthma and chronic rhinosinusitis with nasal polyps (CRSwNP).

• Differentiates by targeting the receptor rather than the ligand, achieving complete pathway shutdown and high potency.

• Data from phase II studies in both indications support ambitions for broad efficacy, clean safety, and self-administration at home.

Clinical trial results and strategy

• Phase II VALIANT trial in severe asthma showed a 56% reduction in annualized asthma exacerbation rate with quarterly dosing, along with improvements in lung function and symptoms.

• VIBRANT phase II trial in CRSwNP demonstrated significant reductions in nasal polyp score and need for surgery or rescue steroids.

• Plans to move both indications into phase III simultaneously, leveraging data from over 500 patients and aiming for a dual-indication launch.

• No induction dosing required; robust receptor occupancy achieved rapidly.

Market landscape and commercial outlook

• Quarterly dosing paired with high efficacy is seen as highly competitive, based on market research with physicians and payers.

• Differentiation on efficacy, broad label, and convenience is key for market access and formulary positioning.

• Biologics penetration in severe asthma remains low, with significant opportunity for new entrants.

• Investment in both auto-injector and prefilled syringe devices to support home and in-office administration.