Background Eltrombopag is a thrombopoietin receptor agonist (TRA). The drug has been approved for the treatment of chronic immune thrombocytopenia (ITP). The platelet (PLT) count response is usually maintained as long as the medication is continued, however once it is stopped, PLT counts typically drop to pretreatment levels at which point patients may be at increased risk of bleeding.

Purpose To describe a patient treated with eltrombopag who unexpectedly achieved sustained PLT count responses after stopping TRA treatment.

Material and methods Demographic, clinical and laboratory data were collected through medical records. We defined TRA induced remission as the achievement of a PLT count >100×10⁹/L; continuation of PLT count >100×10⁹/L during treatment; and persistence of PLT count >100×10⁹/L after treatment was discontinued, without the use of concomitant maintenance therapies. In addition, adverse events during treatment were recorded.

Results The patient was a 75-year-old woman with chronic ITP for 11 years and had received several previous ITP treatments (corticosteroids, intravenous immunoglobulins and dapsone), including splenectomy 8 years before treatment with eltrombopag. Before starting eltrombopag, PLT count was 11 × 10⁹L, and after 2, 6 and 8 weeks of treatment, PLT count increased to 37 × 10⁹L, 83 × 10⁹L and 327 × 10⁹L, respectively. The first dose of eltrombopag was 50 mg and was increased to 75 mg at week 5. Eltrombopag was slowly tapered and then stopped after 11 weeks, with PLT counts >100×10⁹/L and absence of bleeding attained during the treatment. PLT count remained >150×10⁹/L at the last follow-up, 22 months after stopping eltrombopag. Diarrhoea was the only adverse effect recorded during treatment.

Conclusion The patient unexpectedly achieved sustainable PLT count responses after stopping eltrombopag treatment. Short and medium term treatment with TPA may avoid side effects and reduce the financial burden this costly treatment places on healthcare systems. However,the frequency of sustained response after discontinuing eltrombopag without additional therapy for ITP is largely unknown. The communication of such cases is important as it may boost new studies which will re-examine the need for long term use of eltrombopag in all patients with ITP.

No conflict of interest.