PF314 REAL WORLD CLINICAL EFFECTIVENESS AND SAFETY OF CT‐P10 IN PATIENTS WITH DIFFUSE LARGE B‐CELL LYMPHOMA: INTERIM RESULTS FROM A EUROPEAN NON‐INTERVENTIONAL POST‐AUTHORISATION SAFETY STUDY

Background: In February 2017, CT‐P10 became the first biosimilar of rituximab to be approved in Europe for treatment of rheumatic diseases and specific blood cancers including non‐Hodgkin's lymphoma (NHL). Diffuse large B‐cell lymphoma (DLBCL) is the commonest type of NHL, representing an estimated 40–58% of cases (Sant et al, 2010). To date, no studies have investigated the effectiveness or safety of CT‐P10 in patients with DLBCL in the real world clinical setting. Aims: To evaluate the real world clinical effectiveness and safety of CT‐P10 in patients with DLBCL in Europe. Methods: This non‐interventional post‐authorisation safety study is in progress in five European countries (France, Germany, Italy, Spain and the United Kingdom [UK]), and involves collection of data from the medical records of consenting adult patients with DLBCL who were treated with CT‐P10 as part of their routine clinical care. Effectiveness and safety data are being collected for an observation period of 30 months after the index date (date of CT‐P10 initiation) or until death, if sooner. The primary objective is to describe the effectiveness of CT‐P10 (overall survival, progression free survival, CT‐P10 responses), with secondary objectives to describe the safety profile and CT‐P10 treatment pathways. Response to CT‐P10 is as documented by the local investigator. Here we report interim results (patients’ baseline characteristics and preliminary response/safety data), based on a data cut on 18 January 2019. Where n is less than the total number of patients, data were missing. Results: The interim analysis includes 151 patients enrolled from sites in the UK and Spain, with a median 8.9 months (interquartile range [IQR] 6.1–12.6) post‐index observation at the cut‐off. Patients are receiving CT‐P10 as a first‐line ( n   =  138, 91%), second‐line ( n   =  9, 6%) or third‐line ( n   =   4, 3%) DLBCL treatment. Ninety‐five (63%) patients are male. Other patient characteristics at index: median age 70.9 years (IQR 61.5–76.0) ( n   =  149); median disease duration 20 days (IQR 10.5–41.0) ( n   =  147); Eastern Cooperative Oncology Group performance status ( n   =  98): 0 ( n   =   45, 46%), 1 ( n   =   36, 37%), 2 ( n   =   11, 11%), 3 ( n   =   4, 4%) or 4 ( n   =   2, 2%); Ann Arbor stage ( n   =  77): I ( n   =   8, 10%), II ( n   =   9, 11%), III ( n   =  18, 21%), IV ( n   =  40, 48%) or other ( n   =  2, 2%; recorded as ‘at least stage II’). Best responses to CT‐P10 (evaluable in n   =  128) are shown in Fig. 1. Safety of CT‐P10 was evaluable in 128 patients, of whom 118 (92%) experienced adverse events (AEs) during the observation period (732 AEs recorded in total, including infusion‐related reactions), 77 (60%) had AEs of grade 3 and above and 11 (9%) discontinued CT‐P10 due to AEs. Summary/Conclusion: Early results from this ongoing study suggest that a high proportion of patients with DLBCL treated with CT‐P10 in the real world achieve complete or partial responses, similar to the response rates reported previously for reference rituximab (Horvat et al, 2017). Continued recruitment and extended follow‐up will enable more comprehensive analyses of CT‐P10 effectiveness and safety.