Dose adjustment rules
| Platelet count (× 109/L) . | Action . |
|---|---|
| < 50 | Dose increased by 2.0 μg/kg after 2 consecutive weeks of platelet counts < 50. Dose could be increased every 2 weeks. |
| 50-250 | Dose remained constant. |
| > 250-400 | Dose reduced by 1.0 μg/kg after 2 consecutive weeks of platelet counts in this range.* |
| > 400 | Next scheduled dose held, and the dose was reduced by 1.0 μg/kg on the next scheduled dosing day that the platelet count was < 250 × 109/L.† |
| Platelet count (× 109/L) . | Action . |
|---|---|
| < 50 | Dose increased by 2.0 μg/kg after 2 consecutive weeks of platelet counts < 50. Dose could be increased every 2 weeks. |
| 50-250 | Dose remained constant. |
| > 250-400 | Dose reduced by 1.0 μg/kg after 2 consecutive weeks of platelet counts in this range.* |
| > 400 | Next scheduled dose held, and the dose was reduced by 1.0 μg/kg on the next scheduled dosing day that the platelet count was < 250 × 109/L.† |
The dosing algorithm used in this study is different from that specified in the U.S. prescribing information for romiplostim treatment of thrombocytopenia in adults with chronic ITP.35
If the dose was 1.0 μg/kg and a dose reduction was required, the dose was held until the platelet count decreased to ≤ 50 × 109/L. Once the platelet count was ≤ 50 × 109/L, dosing resumed at a dose of 1.0 μg/kg according to the dose adjustment rules.
If the platelet count increased to > 400 as a result of rescue therapy, then the next scheduled dose of investigational product was held and the same dose of investigational product administered on the next scheduled dosing day that the platelet count was < 250 × 109/L.