NCT04154488

A Study of Mavorixafor in Participants With Congenital Neutropenia and Chronic Idiopathic Neutropenia Disorders

A Phase 1b/2, Open-Label, Multicenter Study of Mavorixafor in Patients With Congenital Neutropenia and Chronic Neutropenia Disorders

• Status: Completed
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 32 (actual)
• Sponsor: X4 Pharmaceuticals · Industry
• Sex: All
• Age: 12 Years
• Healthy volunteers: Not accepted

Summary

This is a 2-part study of mavorixafor in participants diagnosed with chronic neutropenia. The main goal of Part 1 (Phase 1b) is to help researchers learn more about how the investigational medicine, mavorixafor, impacts people living with chronic neutropenia (including congenital, idiopathic, and cyclic). In Part 2 (Phase 2), the safety and tolerability of chronic dosing of mavorixafor will be evaluated in a larger participant population and the impact of 6-month chronic dosing of mavorixafor on participant neutropenia.

Detailed description

Part 1: Participants will receive one oral dose of mavorixafor and be monitored for 8 hours to see if neutrophil cell counts increase. Participants screened after implementation of Protocol Version 8.0, do not need to enter Part 1 and can start with the Part 2 Screening visit (Day -28 to Day -1). Part 2: For participants enrolled in the study before implementation of Protocol Version 8.0, Part 2 will include those who completed Part 1 and exhibited a response to treatment. Eligible participants from Part 1 enrolled in the study before implementation of Protocol Version 8.0, can directly roll-over to the Baseline (Day -3 to Day -1) visit in Part 2. Participants will receive once daily oral dosing of mavorixafor for 6 months and be monitored throughout to see if neutrophil cell counts increase. Study visits can be conducted at-home or at one of many study clinic locations, depending on the participant's preference.

Conditions

• Neutropenia

Interventions

Type	Name	Description
DRUG	Mavorixafor	Mavorixafor capsules will be administered per dose and schedule specified in the arm.

Timeline

• Start date: 2021-10-16
• Primary completion: 2024-08-27
• Completion: 2024-08-27
• First posted: 2019-11-06
• Last updated: 2025-08-06

Locations

7 sites across 1 country: United States

Regulatory

• FDA-regulated drug study