Jasper Therapeutics, Inc.

The company is a clinical-stage biotechnology company focused on developing treatments for mast cell-driven diseases like Chronic Spontaneous Urticaria (CSU), Chronic Inducible Urticaria (CIndU), and asthma. The company previously explored programs for diseases where targeting diseased hemopoietic stem cells could provide benefits, such as stem cell transplant conditioning regimens, but these programs have been discontinued. Its primary product candidate, briquilimab, is a monoclonal antibody designed to prevent stem cell factor (SCF) from binding to and signaling through the CD117 (KIT) receptor on mast and stem cells. The SCF/KIT pathway is crucial for mast cell survival, and blocking it may lead to the depletion of these cells throughout the body, including in the lungs and skin, potentially benefiting patients with mast cell-driven diseases. The company is advancing a portfolio of clinical programs in these diseases. For CSU, the company started the Phase 1b/2a BEACON study in late 2023. This randomized, double-blind, placebo-controlled trial evaluates multiple ascending doses of briquilimab, both as a single dose (240mg & 360mg) and with repeat dosing (multiple dose levels from 10mg Q8W up to 240mg Q8W) for adult patients with moderate to severe CSU. Positive preliminary data from the first 8 dosing cohorts (10mg, 40mg, 80mg Q8W, 120mg Q8W & Q12W, 180mg Q8W & Q12W and 240mg SD) were reported in January 2025. Preliminary data from 3 additional cohorts (360mg SD, 240mg Q8W and 240mg/180mg Q8W) were reported in July 2025, and additional positive preliminary data from new patients in the 240mg/180mg Q8W cohort were reported in January 2026. The data from the BEACON study generally show strong efficacy and a favorable safety profile in CSU patients.