Progress
At X4, we are driven to successfully advance innovative therapeutics that truly make a difference in the lives of people with rare immunodeficiencies and few or no treatment options.
What’s it Like Living with Chronic Neutropenia?
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Kevin’s Story
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Vanessa’s Story
What’s it Like Living with WHIM Syndrome?
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Gaby & Willow
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Courtney’s Story
Our Clinical Trials
Chronic Neutropenic Disorders
- Chronic neutropenia is a rare blood condition defined by a decrease in blood neutrophil counts lasting more than three months; people with chronic neutropenia are at higher risk of developing infections and certain cancers and having a reduced quality of life.
- Following successful completion of Phase 1b and Phase 2 clinical trials exploring the use of once-daily oral mavorixafor in the treatment of certain chronic neutropenic disorders, we have initiated a pivotal, global Phase 3 clinical trial.
- The Phase 3 4WARD trial (NCT06056297) aims to evaluate the efficacy, safety, and tolerability of oral once-daily mavorixafor (with or without G-CSF) in people with congenital or acquired primary autoimmune and idiopathic chronic neutropenia who are experiencing recurrent and/or serious infections. For more information, please visit 4WARDstudy.com.
Community and Care Resources
Private Facebook group for people living with WHIM Syndrome. Search under Groups for WHIM Syndrome Community
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The Immune Deficiency Foundation (IDF)
Not-for-profit patient advocacy organization that provides information and resources for people with primary immunodeficiencies (PIs)
International Patient Organization for Primary Immunodeficiencies (IPOPI)
IPOPI is an international not-for-profit organization that advocates for people with primary immunodeficiencies worldwide
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The Jeffrey Modell Foundation (JMF)
Not-for-profit organization devoted to early and precise diagnosis, meaningful treatments and ultimately cures for people with primary immunodeficiencies.
National Neutropenia Network (NNN)
Not-for-profit organization that promotes awareness, education and research for people with severe chronic neutropenia and their families
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National Organization for Rare Disorders (NORD)
A not-for-profit patient advocacy organization dedicated to improving the lives of people living with rare diseases and the organizations that serve them