Long-term eltrombopag demonstrated efficacy in restoring platelet counts and decreasing risk of bleeding in patients with chronic/persistent immune thrombocytopenia (ITP) lasting more than 6 months, according to a study published in Blood.
Previous studies demonstrated that eltrombopag treatment for 6 months or less effectively increased platelet counts and reduced bleeding in patients with chronic ITP. The purpose of this analysis was to evaluate the safety and efficacy of long term therapy with eltrombopag.
For the EXTEND trial, an extension study of 4 clinical trials for eltrombopag, researchers treated 302 patients with chronic ITP with a starting dose of eltrombopag 50 mg daily and titrated doses accordingly. Eligible patients must have had ITP lasting for 6 months or longer and received prior treatment for the disorder.
The median duration of treatment was 2.37 years. Forty-five percent (135) of patients completed the study, and 25% (75) of patients continued treatment for 4 or more years.
Study patients experienced an increase in median platelet count to 50×109/L or greater by week 2. Approximately 86% of patients achieved platelet counts of 50×109/L at least once in the absence of rescue treatment, and 52% of patients achieved continuous response lasting 25 weeks or longer.
Lower rates of response were observed in patients with platelet level lower than 15×109/L, had received greater number of previous therapies, and/or underwent splenectomy.
After 1 year of treatment, bleeding symptoms decreased from 57% at baseline to 16% among study patients.
Reported adverse events that led to the treatment discontinuation of 41 patients included hepatobiliary effects, cataracts, deep vein thrombosis, cerebral infarction, headache, and myelofibrosis.
Wong RSM, Saleh MN, Khelif A, et al. Safety and efficacy of long-term treatment of chronic/persistent ITP with eltrombopag: final results of the EXTEND study [published online October 17, 2017]. Blood. doi: 10.1182/blood-2017-04-748707