Jasper Therapeutics (JSPR) investor relations material

Key program updates

• Lead monoclonal antibody, Briquilimab (BRIC), is in clinical development for chronic spontaneous urticaria (CSU), inducible urticaria, and asthma, with recent data updates in both indications.

• Recent investigation into unexpected lack of response in certain CSU cohorts revealed misdiagnosis in most non-responding patients, not a drug product issue.

• Additional screening measures and third-party reviews have been implemented to improve patient selection and diagnosis accuracy in ongoing and future studies.

• Next data milestone for CSU (Beacon study) is expected in the first half of Q1, including efficacy and safety data for new patients and long-term follow-up.

• Open-label extension (OLE) is ongoing, with nearly all eligible patients rolling over; largest cohort data (35–40 patients) expected early next year.

Clinical trial design and future plans

• Phase II-B study for CSU planned as a three-arm trial (two dosing regimens plus placebo), enrolling 100–120 patients, with an estimated cost of $40–$50 million.

• Optimal dosing regimens for phase II-B likely to include 240 mg Q8 weeks and 240 mg followed by 180 mg Q8 weeks.

• Safety remains a primary focus, with favorable safety profile observed even in patients who did not respond to treatment.

Asthma program highlights

• Allergen challenge study in asthma used a single 180 mg dose, showing significant reduction in sputum eosinophils at 6 and 12 weeks, indicating strong mast cell involvement.

• Study enrollment was halted early due to concerns over drug lot, but subsequent analysis confirmed drug efficacy.

• Next steps may include multi-dose and maintenance dosing studies, with a focus on exacerbation endpoints and broader patient populations (T2 high and T2 low).