(HARBOR) Study to Evaluate Efficacy and Safety of BLU-263 Versus Placebo in Patients With Indolent Systemic Mastocytosis

(HARBOR) Study to Evaluate Efficacy and Safety of BLU-263 Versus Placebo in Patients With Indolent Systemic Mastocytosis is a phase 2/3 interventional study registered as NCT04910685, led by Blueprint Medicines, and recruiting when checked on 2026-09-11. Official title: A Randomised, Double-Blind, Placebo-Controlled Phase 2/3 Study of BLU-263 in Indolent Systemic Mastocytosis. Planned enrolment is 534 participants (estimated). The study started in 2021-11-30 and primary completion is expected in 2032-09-30. No results have been posted on ClinicalTrials.gov.