Therapies in addition to high-dose inhaled corticosteroids (ICSs) and long-acting β2 agonist (LABA).
| Nonbiologic addition | Biologic addition | Number of children |
| Montelukast | 15 | |
| Tiotropium | 4 | |
| Ipratropium | 1 | |
| Triamcinolone | 1 | |
| Montelukast, Tiotropium | 1 | |
| Montelukast, Tiotropium Ipratropium | 1 | |
| Omalizumab | 10 | |
| Montelukast | Omalizumab | 15 |
| Ipratropium | Omalizumab | 1 |
| Montelukast, Tiotropium | Omalizumab | 4 |
| Montelukast, Ipratropium | Omalizumab | 1 |
| Mepolizumab | 5 | |
| Montelukast | Mepolizumab | 2 |
| Tiotropium | Mepolizumab | 1 |
| Ipratropium | Mepolizumab | 1 |
| Montelukast | Dupilumab | 1 |
| Tiotropium | Dupilumab | 1 |
All children were receiving a high dose of inhaled corticosteroids (ICSs), as defined by the SPACE protocol [4]. 15 children were on ICS and LABA alone.