TPO-r Switch is a retrospective study of the patients affected by Immune Thrombopenia (ITP) who received alternatively romiplostim and eltrombopag.

Thrombopoietin mimetics agents are available since 5 years in France through clinical trials first and then after their license. Two drugs are used: romiplostim and eltrombopag. These molecules have the same receptor on the megacaryocyte and induce the same stimulation of this cell leading to the differentiation and the proliferation into platelets. But romiplostim and eltrombopag have 2 different characteristics: the way of administration (oral for eltrombopag and subcutaneous for romiplostim) and the binding site to the C-MPL receptor on megacaryocyte. The aim of this study is to describe ITP patients who received these two drugs alternatively in order to know if there is a benefit for switching these molecules in clinical practice.

Inclusion Criteria:

• Subject has a diagnosis of ITP according to the American Society of Hematology guidelines (Rodeghiero et al, 2009).
• Subject is equal to or greater than 18 years of age.
• Before any study-specific procedure, the appropriate written informed consent must be obtained.
• Subject receiving romiplostim and eltrombopag alternatively
• Available follow-up of 2 months at least for each period

Exclusion Criteria:

- Secondary ITP e.g: thrombopenia related to hepatitis C, HIV, Chronic Lymphocytic Leukemia

Patients with primary Immune Thrombopenia receiving romiplostim and eltrombopag alternatively.