Efficacy and Safety in Patients With Chronic Lymphocytic Leukemia (CLL) Treated With Idelalisib and Rituximab in the Clinical Practice: a GIMEMA-ERIC Study

Inclusion Criteria: * Diagnosis of CLL / Small Lymphocytic Lymphoma (CLL/SLL) according to the World Health Organisation (WHO) classification 2008. * Treatment with idelalisib and rituximab started between the date of Country marketing authorization approval of idelalisib (EMA approval 18/09/2014) and 31/05/2017 given at European centres adhering to the GIMEMA group and the ERIC group. * One of the two following conditions must be satisfied: * Previously untreated CLL requiring therapy according to the NCI criteria (Hallek M et al, Blood 2008)\] with deletion 17p13 and/or TP53 mutation. * Relapsed refractory CLL., i.e. patients who received at least one previous line of treatment using alkylating agents and/or purine analogues with or without monoclonal antibodies, or high dose steroids requiring therapy according to the NCI criteria (Hallek M et al, Blood 2008) * Age ≥ 18 years. * Signed written informed consent, if applicable, according to ICH/EU/GCP and national local law. Exclusion Criteria: * Patients with CLL treated with idelalisib within interventional clinical trials or outside the approved indication. * Patients with: * Transformation of CLL to aggressive lymphomas (Richter's Syndrome). * HIV infection. * Active and uncontrolled HCV and/or HBV infections or liver cirrhosis.