Rare disease drug shows promise in reducing infections

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

* INCLUSION CRITERIA: Subjects are eligible to enter the study if they meet all of the following criteria: 1. Age greater than or equal to 10 and less than or equal to 75 years. 2. Heterozygous mutation in the C-tail of CXCR4 in addition to a clinical diagnosis of WHIMS. 3. Documented neutropenia with a baseline ANC below 1500 cells/microL of blood. 4. History of severe and/or recurrent infections. 5. Willingness to interrupt G-CSF medication, 2 days prior to study drug injection. 6. Must have a local medical provider for medical management. 7. Must be willing to provide blood, plasma, serum, and DNA samples for storage. 8. All study subjects must agree not to become pregnant or impregnate a female. Women of childbearing potential must agree to take appropriate steps to avoid becoming pregnant for the duration of the study. Participants in whom pregnancy is biologically possible must use at least 2 study approved methods of contraception, one of which must be a barrier method, and must continue contraception until 5 months after stopping the study drug: * Male or female condoms with a spermicide, * Diaphragm or cervical cap with spermicide, * Intrauterine device, * Contraceptive pills or patch, Norplant, Depo-Provera or other FDA-approved contraceptive, * Male partner with vasectomy and documented aspermatogenic sterility. 9. Willingness to comply with the study medications, visits, and procedures, as deemed necessary by the principal investigator (PI). EXCLUSION CRITERIA: If any of the following exclusion criteria are met, a subject will not be enrolled in this study: 1. Neutropenia due to maturation defects in the myeloid lineage or a type of neutropenia, which in the investigator s opinion, is unlikely to improve from the medication administered in this study. 2. Pregnant or breast-feeding women. 3. Known hypersensitivity to plerixafor, G-CSF, or any components of the products. 4. Predisposition to or history of life-threatening cardiac arrhythmia. 5. Requiring dialysis or having markedly impaired renal function with a Creatinine Clearance (CrCl) \<15 mL/min. 6. Condition that in the investigator s opinion places a subject at undue risk by participating in the study.