Delayed treatment-free response after romiplostim discontinuation in pediatric chronic immune thrombocytopenia

Tapering and Sustained Remission of Thrombopoietin Receptor Agonists (TPO-RAs): Is it Time for Paediatric ITP?

Thrombopoietin receptor agonists (TPO-Ras; romiplostim/eltrombopag/avatrombopag) have demonstrated high efficacy rates (59-88%) and a good safety profile in clinical trials with adult patients with immune thrombocytopenia (ITP). Similar efficacy and safety results have been observed with romiplostim and eltrombopag in paediatric cohorts. Continuous treatment with TPO-RAs has shown durable responses with long-term use, up to 3 years. The effect of TPO-RAs was generally considered transient, as platelet counts tended to drop to baseline values after a short period of time (about 2 weeks), unless treatment was maintained. Several groups have reported successful discontinuation of TPO-RAs without the need for concomitant treatments. This is referred to as sustained remission off treatment (SROT). Both short- and medium-term treatment with TPO-RAs may reduce costs to our healthcare systems and, more importantly, may reduce the potential side effects that may be associated with continuous TPO-RA treatment. The issue of tapering and discontinuation of TPO-RAs in paediatric patients with ITP has received little attention to date. Given that paediatric ITP has much higher rates of spontaneous remission than ITP in adults, we consider that the possibility of SROT of TPO-RAs in paediatric patients with ITP is a neglected but very relevant issue in this subtype of the disease.

Tapering of thrombopoietin receptor agonist in pediatric patients with chronic immune thrombocytopenia. Is it possible?

It is not clear if platelet responses will be sustained after thrombopoietin receptor agonist (ar-TPO) withdrawal in pediatric patients. A multicenter retrospective observational study was performed in children with chronic immune thrombopenia (cITP) to describe ar-TPO tapering and withdrawal in patients who had achieved a sustained complete response to ar-TPO. Ten patients (eltrombopag (n=6), romiplostim (n=4) were included. Treatment withdrawal was performed after a mean tapering time of 7.6 months. Two patients relapsed (median follow-up time of 24 months). Slow tapering and withdrawal of ar-TPO can be safely performed in cITP pediatric patients after achieving a sustained complete response.

Generic romiplostim for children with persistent or chronic immune thrombocytopenia: Experience from a tertiary care centre in North India

Thrombopoietin receptor agonists are important therapeutic option in children with immune thrombocytopenia (ITP). We evaluated the response, efficacy, safety of a generic form of romiplostim manufactured in India for treating children with persistent/chronic ITP at our centre. Study of 45 children with persistent/chronic ITP was conducted of which 5 discontinued and 40 were included between 2019-2020. Patients received romiplostim for 20 weeks, at a dose of 5 mcg/kg/week. Platelet count at week 1, 3, 20 and 26 was assessed. Predesigned algorithm was used for dose adjustment. After 20 weeks, patients who had platelet count of 50 × 109/L or above were tapered off medication and monitored till 26 weeks. Median platelet count at enrolment was 11 x 109/L (IQR 23 X 109/L). 13/40 children had received >/= three lines of prior ITP therapy. Platelet response (platelet count rise to more than 50×109/L without rescue medications) observed in 26 (65%) patients at week 20. Rescue medication was used in 12/40 children. Sustained platelet response after tapering and stopping romiplostim observed in 22/40 children. No adverse events were considered serious or led to discontinuation of treatment. Our data demonstrated generic romiplostim is well tolerated and efficacious in children with persistent/chronic ITP.