NCT03995108

Efficacy and Safety Study of Mavorixafor in Participants With Warts, Hypogammaglobulinemia, Infections, and Myelokathexis (WHIM) Syndrome

A Phase 3, Randomized, Double-Blind, Placebo-Controlled, Multicenter Study of Mavorixafor in Patients With WHIM Syndrome With Open-Label Extension

• Status: Active Not Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 31 (actual)
• Sponsor: X4 Pharmaceuticals · Industry
• Sex: All
• Age: 12 Years
• Healthy volunteers: Not accepted

Summary

This study has a double-blind, Randomized Placebo-Controlled Period and an Open-Label Period. The primary objective of the Randomized Placebo-Controlled Period is to demonstrate the efficacy of mavorixafor in participants with WHIM syndrome as assessed by increasing levels of circulating neutrophils compared with placebo, and relative to a clinically meaningful threshold. The primary objective of the Open-Label Period is to evaluate the safety and tolerability of mavorixafor in participants with WHIM syndrome. Participants are allowed to continue treatment in the Open-Label Period, if regionally applicable, until mavorixafor becomes commercially available, or until the study is terminated by the Sponsor.

Conditions

• WHIM Syndrome

Interventions

Type	Name	Description
DRUG	Mavorixafor	Mavorixafor provided as 100 mg capsules.
DRUG	Placebo	Placebo matching to mavorixafor capsules

Timeline

• Start date: 2019-10-24
• Primary completion: 2025-12-01
• Completion: 2025-12-01
• First posted: 2019-06-21
• Last updated: 2025-07-29

Locations

23 sites across 13 countries: United States, Australia, Austria, Denmark, France, Hungary, Israel, Italy, Netherlands, Russia, South Korea, Spain, Turkey (Türkiye)

Regulatory

• FDA-regulated drug study