Jasper Therapeutics (JSPR) investor relations material

Drug product investigation and patient response

• Comprehensive analysis confirmed no issues with the drug product or substance, including the lot in question, and no degradation or separation was detected.

• Clinical data showed consistent PK and tryptase responses, indicating the drug was active and depleting mast cells as expected.

• Anomalous efficacy results were observed, with only 2 out of 10 patients responding, compared to typical response rates of 6-7 out of 10.

• Investigation focused on patient selection and site conduct, especially at one site that enrolled five non-responders.

• Redosing and further scrutiny of inclusion criteria were implemented to address potential patient selection issues.

Study adjustments and future data

• All 10 patients in the anomalous cohort will receive at least three doses, providing valuable safety data on repeat dosing at 240 mg.

• Enrollment of 10-12 new patients in two cohorts is underway, with a focus on dosing strategies to optimize efficacy and minimize adverse events.

• More rigorous inclusion-exclusion criteria are now enforced, requiring documented CSU diagnosis from expert physicians.

• Redosing data and investigation conclusions are expected in early Q1 next year.

Asthma study and biological insights

• The asthma study was halted due to concerns about the drug lot but will report data on 12-15 patients by year-end.

• Patients received a single 180 mg dose, with FEV1 and tryptase measured at baseline, six weeks, and twelve weeks.

• The study aims to assess the impact of mast cell depletion on early and late asthmatic responses.

• Results will provide insights into both efficacy signals and the underlying biology of mast cell involvement in asthma.