Table 1.
Demographics and clinical characteristics of participants at baseline (safety population)
| Characteristic | Mavorixafor (n = 14)∗ | Placebo (n = 17)† |
|---|---|---|
| Age, median (range), y | 17.5 (12-58) | 23 (13-72) |
| 12 to <18 y, no. (%) | 7 (50.0) | 8 (47.1) |
| ≥18 y, no. (%) | 7 (50.0) | 9 (52.9) |
| Sex, no. (%) | ||
| Female | 9 (64.3) | 9 (52.9) |
| Male | 5 (35.7) | 8 (47.1) |
| Race, no. (%) | ||
| Asian | 0 | 1 (5.9) |
| White | 13 (92.9) | 16 (94.1) |
| Other | 1 (7.1) | 0 |
| Body mass index, median (range), kg/m2 | 21.6 (17.9-30.5) | 22.0 (16.7-33.0) |
| IgRT use, no. (%) | 6 (42.9) | 8 (47.1) |
| Screening blood count, median (range), ×103/μL | ||
| ANC | 0.15 (0.04-0.39) | 0.2 (0-0.4) |
| ALC | 0.42 (0.26-1.07) | 0.52 (0.1-8.56) |
| AMC | 0.07 (0.03-0.39) | 0.1 (0-0.42) |
| WBC | 0.6 (0.30-1.80) | 0.8 (0.2-9.3) |
| Platelets | 182 (75-341) | 188 (18.0-260) |
| CXCR4 variant, no. (%) | ||
| C terminus‡ | 14 (100) | 17 (100) |
| Any infection in the 12 mo before trial,§ no. (%) | 6 (42.9) | 11 (64.7) |
| Time since WHIM syndrome diagnosis, median (range), y | 8.3 (1.0-24.6) | 8.5 (1.9-22.9) |
| Time since WHIM syndrome symptom,‖ median (range), y | 13.5 (8.6-58.6) | 16.6 (4.7-65.8) |
| Region, no. (%) | ||
| United States | 2 (14.3) | 4 (23.5) |
| Non-United States | 12 (85.7) | 13 (76.5) |
Percentages may not equal 100 because of rounding.
In the mavorixafor group, 1 participant received G-CSF on 2 separate occasions for a total of 10 days for neutropenia. One participant received G-CSF for 3 days for prophylaxis for a vaginal procedure, dexamethasone 4 mg IV once for the vaginal procedure, and oral hydrocortisone 15 mg/d as ongoing replacement therapy after surgical removal of pituitary adenoma. One participant received triamcinolone hexacetonide 20 mg infiltration twice for bilateral popliteal cyst and oral prednisone 50 mg for 16 days with an oral prednisone taper over 37 days for arthritis.
In the placebo group, 1 participant received G-CSF for 10 days for cellulitis. One participant had methylprednisolone 60 mg IV listed as a concomitant medication for rituximab prophylaxis for Evans syndrome with rituximab administered once on day 119.
All CXCR4 variants identified had been previously described as pathogenic.16
Infection history included any infections for the 12 months before dosing (including the screening period before the first dose) from all possible sources of medical records, regardless of the severity of the infection.
Time since WHIM syndrome symptom was defined as first dose date minus date of WHIM syndrome symptom divided by 365.25. Date of WHIM syndrome symptom was recorded per patient reported medical history.