Study of BLU-808 in Chronic Inducible Urticaria (CIndU) and Chronic Spontaneous Urticaria (CSU)

Phase 2

Not yet recruiting

• Conditions: Chronic Inducible Urticaria; Chronic Spontaneous Urticaria
• Interventions: Drug: BLU-808; Drug: Placebo

• Registration Number: NCT06931405
• Lead Sponsor: Blueprint Medicines Corporation

Brief Summary

This is a 2-part, proof-of-concept study to be conducted globally, designed to evaluate the safety, tolerability, clinical activity, pharmacokinetics, and pharmacodynamics of BLU-808, a wild type KIT inhibitor, in participants with CIndU (Part A) or CSU (Part B).

Detailed Description

Not available

Study Timeline

• Status Verified: 2025-04
• Study First Submitted: 2025-04-09
• Study First Submitted QC: 2025-04-09
• Last Update Submitted: 2025-04-09
• Study First Posted: 2025-04-17
• Last Update Posted: 2025-04-17
• Study Start: 2025-05-01
• Primary Completion: 2026-12
• Study Completion: 2026-12

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 105

Inclusion Criteria

• Part A: Confirmed diagnosis of CIndU for ≥3 months prior to Day 1 that is inadequately controlled with second generation H1-antihistamines.
• Part B: Confirmed diagnosis of CSU for ≥6 months prior to Day 1 that is inadequately controlled with second generation H1-antihistamines.

Key

Exclusion Criteria

• Part A: Any active urticaria that may interfere with study assessments.
• Part A: History of cold-induced anaphylaxis.
• Part B: Participant has a clearly defined predominant cause of chronic urticaria or sole trigger such as symptomatic dermographism and cold-induced urticaria.
• Part A and Part B: Any other skin disease associated with chronic itching or angioedema that might influence the study evaluations and results, skin diseases associated with only wheals and no itch, or autoinflammatory diseases with urticarial lesions.
• Part A and Part B: Significant medical, psychiatric, or surgical conditions, or physical findings that may affect participant safety, study drug metabolism, study participation, or assessment of study results.
• Part A and Part B: Abnormal laboratory values that may pose risks or interfere with study participation.
• Part A and Part B: Pregnancy or plans for pregnancy; breastfeeding.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Arm A1 (Part A): BLU-808	BLU-808	BLU-808 will be administered orally.
Arm A3 (Part A): BLU-808	BLU-808	BLU-808 will be administered orally.
Arm B (Part B): BLU-808/Placebo	BLU-808	BLU-808 or matching placebo will be administered orally.
Arm B (Part B): BLU-808/Placebo	Placebo	BLU-808 or matching placebo will be administered orally.

Primary Outcome Measures

Name	Time	Method
Part A and Part B: Number of Participants with Treatment-emergent Adverse Events (TEAEs)	Day 1 through Week 16

Secondary Outcome Measures

Name	Time	Method
Part A: Mean Change From Baseline in Critical Temperature Threshold (CTT) at Week 12	Baseline, Week 12	CTT is the temperature at which CIndU symptoms appear.
Part A: Mean Change From Baseline in Total Fric Score (TFS) at Week 12	Baseline, Week 12	TFS is a measure of CIndU trigger thresholds and disease activity.
Part A and Part B: Complete Response Rate	Week 12
Part A and Part B: Absolute Change From Baseline in Serum Tryptase Concentration at Week 12	Baseline, Week 12
Part A and Part B: Percent Change From Baseline in Serum Tryptase Concentration at Week 12	Baseline, Week 12
Part A and Part B: Area Under the Curve (AUC) of BLU-808	Day 1 to Day 57
Part A and Part B: Maximum Plasma Concentration (Cmax) of BLU-808	Day 1 to Day 57
Part A and Part B: Minimum Plasma Concentration (Cmin) of BLU-808	Day 1 to Day 57
Part A and Part B: Apparent Clearance (CL/F) of BLU-808	Day 1 to Day 57
Part A and Part B: Apparent Volume of Distribution for the Central Compartment (Vc/F) of BLU-808	Day 1 to Day 57
Part A and Part B: Terminal Half-life (t½) of BLU-808	Day 1 to Day 57
Part B: Mean Change From Baseline in Urticaria Activity Score Over 7 Days (UAS7) at Week 12	Baseline, Week 12	UAS7 is a patient-reported outcome used to assess symptoms in participants with CSU.