RESUMO
Eltrombopag is effective and safe in immune thrombocytopenia (ITP). Some patients may sustain their platelet response when treatment is withdrawn but the frequency of this phenomenon is unknown. We retrospectively evaluated 260 adult primary ITP patients (165 women and 95 men; median age, 62 years) treated with eltrombopag after a median time from diagnosis of 24 months. Among the 201 patients who achieved a complete remission (platelet count >100 × 10(9) /l), eltrombopag was discontinued in 80 patients. Reasons for eltrombopag discontinuation were: persistent response despite a reduction in dose over time (n = 33), platelet count >400 × 10(9) /l (n = 29), patient's request (n = 5), elevated aspartate aminotransferase (n = 3), diarrhea (n = 3), thrombosis (n = 3), and other reasons (n = 4). Of the 49 evaluable patients, 26 patients showed sustained response after discontinuing eltrombopag without additional ITP therapy, with a median follow-up of 9 (range, 6-25) months. These patients were characterized by a median time since ITP diagnosis of 46.5 months, with 4/26 having ITP < 1 year. Eleven patients were male and their median age was 59 years. They received a median of 4 previous treatment lines and 42% were splenectomized. No predictive factors of sustained response after eltrombopag withdrawal were identified. Platelet response following eltrombopag cessation may be sustained in an important percentage of adult primary ITP patients who achieved CR with eltrombopag. However, reliable markers for predicting which patients will have this response are needed.
Assuntos
Benzoatos/administração & dosagem , Eritropoese/efeitos dos fármacos , Hematínicos/administração & dosagem , Hidrazinas/administração & dosagem , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Pirazóis/administração & dosagem , Adulto , Idoso , Plaquetas/efeitos dos fármacos , Plaquetas/patologia , Doença Crônica , Esquema de Medicação , Monitoramento de Medicamentos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/patologia , Púrpura Trombocitopênica Idiopática/cirurgia , Receptores de Trombopoetina/agonistas , Receptores de Trombopoetina/genética , Receptores de Trombopoetina/metabolismo , Recidiva , Indução de Remissão , Estudos Retrospectivos , Esplenectomia , Resultado do TratamentoRESUMO
Drug-induced immune thrombocytopenia may occur secondary to several chemotherapeutic agents or new targeted monoclonal antibodies, but thrombocytopenia induced by trastuzumab is a very rare occurrence. We report a case of severe thrombocytopenia related to the administration of trastuzumab six months after the first exposure.