Characteristics of first- and second-line drugs
| Agent . | Indication . | Administration . | Response rates . | Main side effects . |
|---|---|---|---|---|
| Predniso(lo)ne | Initial therapy | Oral, short course of up to 8 weeks | Durable response rates 30%-35% | Weight gain, insomnia, glucose intolerance, mood changes, hypertension, osteoporosis |
| Dexamethasone | Initial therapy | Oral, pulse therapy over 4 days, up to 3 courses | Responses at 6 months of 35%-40% | |
| IVIg | Initial therapy and later phases as rescue | Intravenous, 1 to 5 days, can be repeated if needed | 80% achieve short-term transient response | Headache, aseptic meningitis, thromboembolism |
| Romiplostim (TPO-RA) | Subsequent therapy | Weekly subcutaneous administration of 1-10 ug/kg,* maintenance therapy | Durable response rates of 38% in splenectomized patients and 56% in non-splenectomized17§ | Key special warnings and precautions for use for allTPO-RAs include: increased thromboembolic complications; increased bone marrow reticulin; eltrombopag can cause hepatotoxicity |
| Eltrombopag (TPO-RA) | Subsequent therapy | Oral, daily administration of 25-75 mg,* maintenance therapy | Durable response rates on treatment of 60%-70%15§ | |
| Avatrombopag (TPO-RA) | Subsequent therapy | Oral, daily administration of 20-40 mg,* maintenance therapy | Durable response rates of 34%16§ | |
| Rituximab (B-cell depleting agent) | Subsequent therapy | 2 IV infusions of 1000 mg 2 weeks apart or 4 weekly IV infusions of 375 mg/m2, with lower doses showing effect in studies; remission-inducing therapy | Durable response rate of 39% at 6 months1 and 29% at 5 years28 | Infusion-related reactions, immunosuppression, and slight increase in the risk of bacterial infections; reactivation of hepatitis B virus; serum sickness disease; secondary hypogammaglobulinemia |
| Fostamatinib Spleen tyrosine kinase inhibitor | Subsequent therapy | Oral, daily administration of 100-150 mg × 2, maintenance therapy | Durable response rates of 18%27§ | Hypertension, diarrhea, hepatotoxicity, neutropenia |
| Agent . | Indication . | Administration . | Response rates . | Main side effects . |
|---|---|---|---|---|
| Predniso(lo)ne | Initial therapy | Oral, short course of up to 8 weeks | Durable response rates 30%-35% | Weight gain, insomnia, glucose intolerance, mood changes, hypertension, osteoporosis |
| Dexamethasone | Initial therapy | Oral, pulse therapy over 4 days, up to 3 courses | Responses at 6 months of 35%-40% | |
| IVIg | Initial therapy and later phases as rescue | Intravenous, 1 to 5 days, can be repeated if needed | 80% achieve short-term transient response | Headache, aseptic meningitis, thromboembolism |
| Romiplostim (TPO-RA) | Subsequent therapy | Weekly subcutaneous administration of 1-10 ug/kg,* maintenance therapy | Durable response rates of 38% in splenectomized patients and 56% in non-splenectomized17§ | Key special warnings and precautions for use for allTPO-RAs include: increased thromboembolic complications; increased bone marrow reticulin; eltrombopag can cause hepatotoxicity |
| Eltrombopag (TPO-RA) | Subsequent therapy | Oral, daily administration of 25-75 mg,* maintenance therapy | Durable response rates on treatment of 60%-70%15§ | |
| Avatrombopag (TPO-RA) | Subsequent therapy | Oral, daily administration of 20-40 mg,* maintenance therapy | Durable response rates of 34%16§ | |
| Rituximab (B-cell depleting agent) | Subsequent therapy | 2 IV infusions of 1000 mg 2 weeks apart or 4 weekly IV infusions of 375 mg/m2, with lower doses showing effect in studies; remission-inducing therapy | Durable response rate of 39% at 6 months1 and 29% at 5 years28 | Infusion-related reactions, immunosuppression, and slight increase in the risk of bacterial infections; reactivation of hepatitis B virus; serum sickness disease; secondary hypogammaglobulinemia |
| Fostamatinib Spleen tyrosine kinase inhibitor | Subsequent therapy | Oral, daily administration of 100-150 mg × 2, maintenance therapy | Durable response rates of 18%27§ | Hypertension, diarrhea, hepatotoxicity, neutropenia |
Occasionally lower doses are needed. §In pivotal phase 3 trials, all agents demonstrated significantly greater durable platelet response rates vs placebo at 6 months; however, definitions of durable platelet response rate differed slightly, making direct cross-study comparisons difficult.
IVIg, IV immunoglobulin; TRO-RA, thrombopoietin receptor agonist.