Jasper Therapeutics (JSPR) H.C. Wainwright 26th Annual Global Investment Conference 2024 summary

Pipeline overview and recent milestones

• Lead program briquilimab targets c-Kit on mast cells, with ongoing trials in chronic spontaneous urticaria (CSU) and inducible urticaria (CIndU).

• Health Canada cleared the CTA/IND for an asthma study, aiming for first patient enrollment in Q4.

• Phase I data in healthy volunteers showed dose-dependent mast cell depletion, informing phase II dosing strategies.

• A new 180 mg Q8 weekly dose cohort was added to the phase II study due to strong enrollment and flexible study design.

• Data readouts for CSU and CIndU studies are expected in Q4, with asthma study initiation also planned for Q4.

Mechanism of action and differentiation

• Briquilimab induces mast cell apoptosis by blocking c-Kit, the primary survival pathway for mast cells.

• Unlike other drugs, briquilimab depletes rather than inhibits mast cells, potentially offering longer-lasting effects.

• Structurally, briquilimab has fewer Fc modifications than barzolvolimab, possibly reducing immunogenicity.

• Briquilimab has a shorter half-life (9 days) compared to barzolvolimab (21–22 days), which may confer safety advantages.

• Binds with higher affinity to the SCF binding pocket, potentially increasing potency.

Clinical development and competitive landscape

• Phase II BEACON study in CSU uses dose escalation based on phase I depletion data, with primary endpoint UAS7 at 12 weeks.

• The CIndU SPOTLIGHT study mirrors Celldex's phase I design, with a single dose and 12-week follow-up.

• Barzolvolimab is considered the benchmark; both drugs are the only ones shown to deplete mast cells.

• Market opportunity is significant, with analogies drawn to the psoriasis market's expansion.

• Oral mast cell inhibitors require continuous dosing, while depletion strategies may offer compliance and efficacy benefits.