Multicenter, retrospective, European study to evaluate standards of use of thrombopoietin receptor agonists in adult patients with primary immune thrombocytopenia (ITP). Data will be collected by retrospectively reviewing the medical records of patients with ITP who started treatment with thrombopoietin analogues (regardless of phase of the disease) between January 2014 and December 2016.

Each of the 18 sites across UK, Spain, Italy, Norway, France and Switzerland will collect the data from all the patients with ITP who meet the inclusion criteria and agree to participate in the study by signing the informed consent. In order to prevent screening bias, the medical records will be consecutively screened by the investigators, starting with the oldest (regarding start of ITP therapy with TPO-RA), by selecting patients who started therapy with agonists on the date nearest to January 2014. The data will be obtained in a retrospective, non-interventionist manner to meet this study’s objective, by reviewing the patient’s medical records.

The project is coordinated by ERCI founding member Maria Luisa Lozano, from Hospital Universitario Morales Meseguer, Universidad de Murcia, Spain and is conducted in collaboration with the Hematology Project Foundation, Vicenza, Italy.

Registries are cornerstone sources of data in rare diseases like immune thrombocytopenia. The European Research Consortium on ITP (ERCI) defined some priority unmet needs as regards knowledge about epidemiology and pharmacoepidemiology of ITP in order to improve patient care. This project provides an overview of existing registries in Europe (both clinical registries and population-based cohorts) and is meant to propose a harmonization of existing registries and to response the need of a European registry on ITP to analyze the discrepancies in treatment availability, increase the number of informative patients for specific investigations like the assessment of  risks of rare events and of real world use, effectiveness and safety of newly marketed ITP drugs, and to facilitate the selection of patients in clinical trials.

The project is divided in three steps:

1) Record of available registries and description of their structure (clinical registries versus cohorts built in health insurance databases) and content (inclusion criteria, date of start, categories of variables recorded, time of data collection during the follow-up, availability of biological collections and of quality of life/patient reported outcomes). This step has been achieved in 2022 (see publication at: https://pubmed.ncbi.nlm.nih.gov/35303315/). Given the existence of major sources of high-quality data, the results of this first step reinforced the project to harmonize existing registries instead of building a new, concurrent European registry, which would be much more time-consuming and expensive.

2) Organization of meetings with registry coordinators to achieve an in-depth review of recorded variables in each registry (locations in the database structure, tables, labels, codes).

3) Redaction of common extraction models to extract similar data from each registry and transform the variables using the same coding system.

The ERCI group is currently searching funds to achieve steps 2-3.

The project is coordinated by ERCI founding member Guillaume Moulis, from the Department of Internal Medicine, Toulouse University Hospital, France.