Safety and efficacy of eltrombopag plus pulsed dexamethasone as first-line therapy for immune thrombocytopenia.

Current first-line treatments for immune thrombocytopenia (ITP) usually have transient effects and sustained platelet response off therapy remains low. We evaluated whether eltrombopag plus pulsed dexamethasone as first-line therapy can increase the proportion of patients maintaining platelet counts >50 × 109 /l for a prolonged period without further ITP therapy. Treatment consisted of eltrombopag 25-75 mg daily according to platelet response for 12 weeks plus dexamethasone, 40 mg daily for four consecutive days every four weeks for 1-3 courses. Primary endpoint was durable response off therapy defined as maintaining platelet counts >50 × 109 /l for more than six months without further ITP therapy. Fifty ITP subjects were enrolled between November 2014 and March 2019. Out of 46 evaluable subjects, 26 (56·5%) had achieved the primary endpoint. The median platelet counts at six months off-treatment follow-up were 158 × 109 /l. Only two out of 26 responders had relapsed at eight- and nine-month follow-up. The remaining 24 are still maintaining platelet counts >50 × 109 /l, the longest over three years. All subjects tolerated treatment well and no Grade 3 or above adverse effects were reported. Eltrombopag plus pulsed dexamethasone as a first-line therapy could result in durable response off therapy in a significant number of ITP subjects.