Second‐line treatments and outcomes for immune thrombocytopenia: A retrospective study with electronic health records

BACKGROUND: Second‐line treatment for immune thrombocytopenia (ITP) is not well reported for patients treated in real‐world clinical settings. OBJECTIVE: The purpose of this study was to compare outcomes of four second‐line treatments for ITP. PATIENTS/METHODS: Included adult patients had at least two medical records containing ITP diagnoses and second‐line eltrombopag, romiplostim, rituximab, or splenectomy. Date of treatment initiation or splenectomy was set as index date, between July 1, 2008, and March 31, 2017. Patients had first‐line corticosteroid or intravenous immune globulin treatment and continuous database activity from 6 months before to 12 months after index. Patient characteristics, treatment patterns, platelet counts, bleeding‐related episodes (BREs), and thrombotic events (TEs) were compared by second‐line treatment cohort. RESULTS: The sample included 3332 patients (mean age, 60.5 years; 52.3% female): eltrombopag (5.8%), romiplostim (9.9%), rituximab (73.3%), and splenectomy (11.0%). Patients having splenectomy were younger, more likely female and commercially insured, and less likely to require a third line of treatment than medical regimen cohorts. Proportions of patients having treatment‐free (≥180 days with no second‐line index or rescue agent) periods varied significantly (P = .01) by regimen: 33% for eltrombopag, 23% for romiplostim, 26% for rituximab, and 17% for splenectomy. All regimens significantly improved platelet counts, while TE and BRE rates differed significantly (P = .03 and P = .01, respectively) when all treatment groups were compared. CONCLUSIONS: Over an average 7‐year follow‐up, all second‐line regimens improved platelet counts, but eltrombopag yielded the highest proportion of patients with completely treatment‐free periods of at least 180 days.