Short Term Treatment With Thrombopoietin-Receptor Agonists For Patients With Immune Thrombocytopenic Purpura (ITP) Before Splenectomy

The thrombopoietin-receptor agonists (romiplostim and eltrombopag) were approved recently as treatments for patients with immune thrombocytopenic purpura (ITP). Splenectomy remains a common second line treatment for ITP with the highest remission rate compared with alternative therapies. It has been reported that splenectomy can be safely performed in patients with a platelet count of 40-50,000 per cubic millimeter but many patients do not reach these values. Intravenous immune globulins (IVIG) are often used before splenectomy in order to increase the platelet count before surgery.

The aim of this study was to determine whether a short course of thrombopoietin-receptor agonists can be used as a reliable and safe treatment to increase the platelet count in patients with ITP before splenectomy.

Between 2010 and 2012, fifteen patients with ITP, all refractory to steroids, were scheduled for splenectomy. Treatment with thrombopoietin-receptor agonists (romiplostim or eltrombopag) was started 3 weeks before splenectomy. Eight patients received eltrombopag at a dose of 50 mg/day orally until 3 days before splenectomy. For romiplostim, a subcutaneous injection of 3 mcg/kg was given weekly to 7 patients. The last injection was given one week before splenectomy. Complete blood count was repeated every week and the dose of romiplostim was adjusted (up to 10 mcg/kg or down to 1 mcg/kg) based on the platelet count increment. Response was defined as a platelet count of 50,000 or more per cubic millimeter.

Mean platelet count before treatment was 11,000±8,000 cells per cubic millimeter. All patients, except one patient on romiplostim, responded to the treatment with a mean platelet count of 74± 25 cells per cubic millimeter on the day of splenectomy (p<0.01). Similar effect was noticed among responders of the two drugs. Four patients from the romiplostim group responded to a 3 mcg/kg dose. Two patients responded to increased doses of 7 and 10 and 10 mcg/kg. One patient did not respond to 10 mcg/kg of romiplostim but later responded to IVIG. The two drugs were well tolerated with no side effects except for mild liver function abnormalities in one patient in the eltrombopag group. No thromboembolic complications or excessive bleeding were reported for these patients.

In summary, we report that a short course of thrombopoietin-receptors agonists can effectively and safely increase the platelet count in steroid resistant ITP patients before splenectomy.