The research project is trying to find out if we can improve the results of best available chemotherapy for Chronic Lymphocytic Leukaemia (CLL) by the addition of a new drug called lenalidomide.

INTERVENTION: After initial chemotherapy (the standard routine chemotherapy given to patients with CLL) patients will be randomised to either follow‐up or to new medication Lenalidomide. Patients randomised to followup will visit their clinician regularly and have blood tests for the same amount of time as those randomised to Lenalidomide. Those randomised to Lenalidomide will commence at 5mg (2.5 mg for those with renal impairment) and, if tolerated, escalate to a maximum of 10mg (5mg in renally impaired) in 2.5mg increments every 2 cycles. At day 28 patient will undergo blood tests to ensure safe to continue with treatment. A new cycle will commence at the appropriate dose. This will occur for 24 months (2years). CONDITION: Chronic Lymphocytic Leukaemia (CLL) PRIMARY OUTCOME: Time to clinical disease progression, or death, from the date of randomisation. Patients will be monitored for evidence of disease progresssion using clinical, radiological and flow cytometry according to standardised international criteria. SECONDARY OUTCOME: Conversion to Minimal Residual Disease (MRD) negativity for randomized patients. Measured by flow cytometry of Bone Marrow sample. Overall survival, measured by clinician at follow up. Percentage of patients with improvement in disease response. Results from routine tests such as bone marrow biospy and blood test will be used. Time to requirement for next therapy after Lenalidomide. Tolerability of Lenalidomide consolidation.Measured by assessing patient ability to go on with next planned cycles ‐ involves blood tests to ensure blood counts have recovered satisfactorily so as next cycle can be commenced. INCLUSION CRITERIA: B‐cell Chronic Lymphocytic Leukaemia (CLL) confirmed according to World Health Organisation (WHO) Criteria. Age 18 years or older. Pre‐Fludarabine chlorambucil (FC)/Fludarabine chlorambucil rituximab (FCR) chemotherapy blood sample desirable. Completed 4 to 6 cycles of FC or FCR, and within 3 – 6 months of last dose of chemotherapy. Achieved partial response or better following chemotherapy. Evidence of residual disease: at least one of clinical or CT lymphadenopathy >1.5cm, clinical or Computed Axial Tomography Scan (CT) hepatomegaly or splenomegaly, positive bone marrow histology (including the persistence of three or more lymphoid nodules, regardless of immunohistochemical features), or detectable minimal residual disease (MRD) in blood or marrow obtained from flow cytometry result performed at Westmead Hospital Flow Cytometry Unit. Adequate haematological recovery following chemotherapy (haemoglobin (Hb) > 110g/L, neutrophils > 1.5 x 10^9/L, platelet