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

Source: https://onco.cc/trials/nct04910685/  
OnCo record `nct04910685` (Trial). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

A phase 2/3 trial testing Elenestinib in systemic mastocytosis, now recruiting.

## Summary

(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 on the registry. 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.

## Fields

- Kind: Trial
- Status: recruiting
- Last checked: 2026-09-11
- Also known as: HARBOR
- Tags: ctgov-ingest
- Registry id: NCT04910685
- Phase: 2/3
- Setting: A Randomized, Double-Blind, Placebo-Controlled Phase 2/3 Study of BLU-263 in Indolent Systemic Mastocytosis
- Sponsor: Blueprint Medicines
- Enrolled: 534

## Sources

- ClinicalTrials.gov NCT04910685: https://clinicaltrials.gov/study/NCT04910685

## Connected records

- cancers: [Indolent and smouldering systemic mastocytosis](https://onco.cc/cancers/indolent-systemic-mastocytosis/), [Systemic mastocytosis](https://onco.cc/cancers/systemic-mastocytosis/)
- drugs: [Elenestinib](https://onco.cc/drugs/elenestinib/)
- companies: [Sanofi](https://onco.cc/companies/sanofi/)

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JSON: https://onco.cc/api/v1/entities/nct04910685.json