CONTEXT
toxicity, toxicities, thrombocytopenia, MDS, cytopenias, anemia, low-risk myelodysplastic syndromes, chronic hepatitis C
VIRUS INFECTION, THROMBOCYTOPENIA, CYTOPENIAS, ANEMIA, IMMUNE THROMBOCYTOPENIC PURPURA, APLASTIC ANEMIA, CHRONIC HEPATITIS C


Treatment of severe thrombocytopenia in patients with low-risk myelodysplastic syndromes (MDS) is a serious unmet need. Although we have previously documented the short-term efficacy and safety of the thrombopoietin receptor agonist eltrombopag in improving thrombocytopenia in low-risk MDS in the interim analysis of the first 50% of cases enrolled in the EQOL-MDS trial, we report on the second stage, which evaluates the long-term efficacy and safety of eltrombopag.
In the full data set (N = 169) and longer follow-up (60 months), a high response rate is confirmed, which, in addition, is durable (60% still maintaining response at 5 years), and an improvement in other cytopenias was observed. Eltrombopag was observed to have an acceptable toxicity profile in the long term and is effective in raising and maintaining PLT counts at a safe level without any associated risk of MDS progression.
Administration of eltrombopag results in durable improvements in PLT counts in patients with low-risk MDS and appears to be well tolerated with acceptable toxicities to date. Longer-term follow-up of the trial cohort will be important.**Relevance section written by Although anemia prevails, severe thrombocytopenia (<30 × 10Thrombopoietin is the key regulator of PLT production by binding to its specific receptor thrombopoietin (TPO) receptor (TPO-R), on the megakaryocytic surface.Eltrombopag is an orally bioavailable, small molecule acting as a TPO-R agonist, approved for the treatment of thrombocytopenia of chronic immune thrombocytopenic purpura, chronic hepatitis C virus infection, and for acquired severe aplastic anemia.We have previously reported on the short-term outcome of the first 90 cases enrolled in the EQOL-MDS trial, a phase-II, randomized study designed to assess eltrombopag efficacy and safety compared with placebo in patients with lower-risk MDS with severe persistent thrombocytopenia.