IBRORS-MCL Study: A Spanish Retrospective and Observational Study of Relapsed/Refractory Mantle-Cell Lymphoma (MCL) Treated with Ibrutinib in Routine Clinical Practice

Context: Ibrutinib is a first-in-class oral inhibitor of Bruton's tyrosine kinase, has been established as a standard-of-care (SOC) treatment for R/R MCL. The clinical benefits with ibrutinib has been demonstrated in multiple trials and real-world studies.1-3 Objective: To describe ibrutinib outcomes in real-world patients in Spain. Design: IBRORS is a retrospective multicentre observational study of patients with confirmed diagnosis of R/R MCL who were treated with ibrutinib from January 2016 to March 2019 (6 months prior to the start of the study). The primary end point was PFS. Disease characteristics, previous therapies used, response rates, and survival outcomes with ibrutinib were also evaluated. Patients or other participants: The analysis included 66 evaluable patients from 24 centres in Spain. Median age at diagnosis was 64.5 years (range 57-72), and 78.8% were male. Baseline comorbidities of interest include: hypertension (47%), dyslipidemia (36.4%), and cardiovascular disorders (21.2%). Interventions: Patients had a median of 2 prior lines of therapy (range 1-8). Among the pre-ibrutinib treatments used, the most common treatment was bendamustine plus rituximab in 20.7% of cases, followed by R-CHOP-like combinations in 19.3% and Hyper-CVAD in 16.4%. Results: With a median follow-up of 14.2 months after Ibrutinib initiation, Ibrutinib treatment led to an ORR of 67.8% with a complete response in 24 patients (36.4%) and partial response in 16 patients (24.2%). Median PFS was 20.0 months (95% CI, 8.8-31.1) and median OS was 32 months (95% CI, 22.6-41.3). Adverse events were reported in 43 patients (65.1%). Atrial fibrillation or associated cardiovascular diseases were reported in 2 patients and no major hemorrhages were reported. Conclusions: IBRORS provides information on the first real-world study of ibrutinib use in clinical practice in Spain. The results suggest that ibrutinib is mostly being used in first and second relapses. The data evaluated confirms the favorable adverse event profile and manageability of ibrutinib in real-world clinical practice. References: [1] Wang et al. Blood. 2015; 126:739-745. [2] Wang et al. NEJM. 2013; 369:507-16. [3] Le Gouill et al. EHA 2019, PS1264.