Long Term Discontinuation of Eltrombopag after Remission in Primary Immune Thrombocytopenia: 8-Year Follow-up Data from 15 Spanish Centers

• Published in: Blood 2019-11, Vol.134 (Supplement_1), p.2352-2352
• Main Authors: Gonzalez-Lopez, Tomas Jose, Fernandez-Fuertes, Fernando, Pascual Izquierdo, Maria Cristina, Caparros, Isabel, Bernat, Silvia, Pastoriza, Carmen, Martínez-Badas, Maria Paz, Olivera, Pável E, Caballero, Gonzalo, Hernandez-Rivas, Jose Angel, Martínez-Carballeira, Daniel, Soto Ortega, Inmaculada, Perez Segura, Gloria, Regalado, Isabel, Sánchez-González, Blanca, Jarque, Isidro, garcia Frade, Luis Javier, Sanz, Miguel A.
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2019-129274

Background: Successful discontinuation of eltrombopag in certain immune thrombocytopenia (ITP) patients after complete response has already been demonstrated. However, the frequency of this phenomenon and type of candidate patients are still matter of discussion. Moreover, possibility of long term discontinuation responses is not clearly established. Methods: Here we retrospectively evaluated our whole cohort of 508 adult patients (aged 18 years or more) with primary ITP treated with eltrombopag included in the Spanish Eltrombopag Registry with a focus on the patients who achieved a durable (at least six months) platelet response after stopping eltrombopag. Successful discontinuation of eltrombopag (SDOE) was defined as those patients who reached remission and maintained platelet counts ≥ 50x109/l for at least 6 months in absence of eltrombopag or any rescue therapies administered. Long term discontinuation of eltrombopag (LTDOE) was defined as those patients who reached remission and maintained platelet counts ≥ 50x109/l for at least 36 months in the absence of eltrombopag or any rescue therapies administered. The study was approved by the Hospital Universitario de Burgos Ethics Committee and fulfilled Helsinki declaration standards. Results: While 37.4% of our patients relapsed of ITP with subsequent platelet count drop sometime during first six months of discontinuation of eltrombopag, a total of 74 patients (14.6%) were able to achieve SDOE. The median age of SDOE patients was 62 [range, 47-79] years. There were 47 women and 27 men. According to the standard definition, patients were allocated to newly diagnosed (n=17), persistent (n=15) and chronic (n=42) ITP groups. The median time from diagnosis to eltrombopag initiation was 31 [range, 4-104] months. The median number of previous therapies was 2 [range, 1-2], including splenectomy (14%), rituximab (18%) and romiplostim (12%). As expected, all patients but 1 achieved a complete response (platelet count ≥100 x 109/L) prior to eltrombopag discontinuation The median duration of eltrombopag treatment was 7 [range, 2-19] months. Reasons for eltrombopag discontinuation were: persistent response despite a reduction in dose over time (n=43), platelet count >400x109/L (n=16), aspartate aminotransferase elevation (n=5), diarrhea (n=4), thrombosis (n=3), patient's request (n=2) and other reasons (n=1). Analysis of these SDOE discontinued patients show that with a median follow-up of 55 [range, 29-79] months, 38