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

• Status: Recruiting
• Trial end date: 2022-07-29
• Target enrollment: 0
• Participant gender: All

Summary

This Phase 1b study will determine the safety and tolerability of mavorixafor in participants with severe chronic idiopathic neutropenia (CIN) and selected congenital neutropenia disorders. The anticipated enrollment is up to 25 participants.

• Phase: Phase 1
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: X4 Pharmaceuticals

Criteria

Key Inclusion Criteria:

• For all participants:

• Sign the informed consent form (ICF) and be willing and able to comply with the protocol.

• Weigh ≥15 kg

• Agree to use contraception as follows:

i) Women of childbearing potential (WOCBP): agree to use a highly-effective form of contraception.

• Participants who are on granulocyte-colony stimulating factor (G-CSF) must be on a stable dose for at least 14 days prior to enrollment and for the duration of the study.

• Participants who are not on G-CSF must be off for at least 14 days prior to enrollment and for the duration of the study.

• Have an absolute neutrophil count (ANC) < 1000 cells/µL at the screening and baseline visits.

• Participants on G-CSF are allowed if their screening and baseline ANC is ≥1000 cells/uL. Participants with cyclical neutropenia are required to have ANC <1000 cells/ µL only at the baseline visit

• Have been diagnosed chronic neutropenia for at least 6 months prior to screening that is not attributable to medications, active or recent (within 3 months) infections, or malignant cause.

Key Exclusion Criteria:

• Known systemic hypersensitivity to the mavorixafor drug substance or its inactive ingredients.

• Is pregnant or nursing.

• Known history of a positive serology or viral load for human immunodeficiency virus (HIV) or a known history of acquired immune deficiency syndrome.

• At screening, has laboratory test results meeting one or more of the following criteria:

• Positive hepatitis C virus (HCV) antibodies with confirmation by HCV-ribonucleic acid polymerase chain reaction reflex testing.

• Positive hepatitis B surface antigen (HBsAg) or hepatitis B core antibody (HBcAb).

Note: If a participant tests negative for HBsAg but positive for HBcAb, the participant would be considered eligible if the participant tests positive for antibody to HBsAg reflex testing.

• At screening, has laboratory test results meeting one or more of the following criteria:

• Hemoglobin <9.0 grams/deciliter (g/dL)

• Platelet count <30,000/μL

• Mild/moderate renal impairment 30 to 60 glomerular filtration rate

• Serum aspartate transaminase >2.5 * upper limit of normal (ULN)

• Serum alanine transaminase >2.5 * ULN

• Total bilirubin >1.5 * ULN (unless due to Gilbert's syndrome, in which case total bilirubin greater than or equal to (≥) 3.0 * ULN and direct bilirubin >1.5 * ULN)

• Within 2 weeks before Day 1, received any of the following treatments:

• Glucocorticoids (>5 mg prednisone equivalent per day)

• Medication prohibited based on cytochrome P450 (CYP) and/or transporter-based (such as, P-glycoprotein ([P-gp]) potential for drug-drug interaction.

• At the planned initiation of study drug, has an infection requiring use of antibiotics (systemic or inhaled) or took systemic antibiotics within 4 weeks before Day 1.

• Has any other medical or personal condition that, in the opinion of the Investigator, may potentially compromise the safety or compliance of the participant, or may preclude the participant's successful completion of the clinical study.

• Inability to ingest capsules of study drug as presented.

• Has a history of any hematologic malignancy.

• Diagnosed or have congenital long QT syndrome. Any history of clinically significant ventricular arrhythmias (such as ventricular tachycardia, ventricular fibrillation, or torsades de pointes); any history of arrhythmia will be discussed with the sponsor's medical monitor before participant's entry into the study.

• Prolonged corrected QT interval (QTc) using Fridericia's formula (QTcF) on pre-entry electrocardiogram (ECG) (≥450 milliseconds [ms]).