Infection-related transient loss of response and other early side effects in chronic ITP during treatment with thrombopoietin mimetics.

BACKGROUND: The new thrombopoietin mimetics (TM) romiplostim (Nplate®) and eltrombopag (Revolade®) have been demonstrated to increase platelet counts in the majority of patients with chronic autoimmune thrombocytopenia (ITP). Platelet counts in chronic ITP may fluctuate significantly due to infections, but it is unknown if this holds true in patients being treated with TM.

PATIENTS AND METHODS: 13 adult patients with refractory chronic ITP were treated with the new TM. 10 patients were only treated with eltrombopag, 2 were initially treated with eltrombopag and subsequently switched to romiplostim, and 1 patient was only treated with romiplostim.

RESULTS: Ten patients responded to eltrombopag, and 4 of these patients experienced a transient loss of response following infection. Two patients developed bleeding symptoms, with 1 of these patients requiring platelet transfusion. All 3 patients treated with romiplostim responded, and 1 of these patients experienced also a transient loss of response following infections.

CONCLUSIONS: Patients receiving treatment with TM may experience adverse platelet count fluctuations during infections.