Inclusion Criteria:

1. Diagnosis of chronic lymphocytic leukemia with no history of previous treatments with
monoclonal antibodies or chemotherapy.

2. Subjects must have an indication for treatment as defined by the NCI Working Group
Guidelines

3. Understand and voluntarily sign an informed consent form.

4. Age ≥18 years at the time of signing the informed consent form.

5. Able to adhere to the study visit schedule and other protocol requirements.

6. ECOG performance status of ≤ 2 at study entry (see Appendix A).

7. Laboratory test results within these ranges: Absolute neutrophil count ≥ 1.0 x 109/L,
Platelet count ≥ 50 x 109/L, Serum creatinine ≤ 1.5 mg/dL, Total bilirubin ≤ 1.5
mg/dL, AST & ALT ≤ 2 x ULN

8. Females of childbearing potential (FCBP)† must have a negative serum or urine
pregnancy test with a sensitivity of at least 50 mIU/mL within 10 - 14 days prior to
and again within 24 hours of starting lenalidomide and must either commit to
continued abstinence from heterosexual intercourse or begin TWO acceptable methods of
birth control, one highly effective method and one additional effective method AT THE
SAME TIME, at least 28 days before she starts taking lenalidomide. FCBP must also
agree to ongoing pregnancy testing. Men must agree to use a latex condom during
sexual contact with a FCBP even if they have had a successful vasectomy. All
patients must be counseled at a minimum of every 28 days about pregnancy precautions
and risks of fetal exposure.

9. Disease free of prior malignancies for ≥ 2 years with exception of currently treated
basal cell, squamous cell carcinoma of the skin, or carcinoma "insitu" of the cervix
or breast

Exclusion Criteria:

1. Previous treatment for CLL with chemotherapy or monoclonal antibodies

2. Known Hepatitis B Ag positive, Hepatitis C positive patients

3. Known HIV positive patients

4. Patients with uncontrolled Autoimmune Hemolytic Anemia (AIHA) or autoimmune
thrombocytopenia (ITP).

5. Inability to provide informed consent.

6. Concurrent malignancy (excluding basal and squamous cell skin cancers).

7. Active fungal, bacterial, and/or viral infection.

8. Any serious medical condition, laboratory abnormality, or psychiatric illness that
would prevent the subject from signing the informed consent form.

9. Pregnant or breast-feeding females. (Lactating females must agree not to breast feed
while taking lenalidomide).

10. Any condition, including the presence of laboratory abnormalities, which places the
subject at unacceptable risk if he/she were to participate in the study or confounds
the ability to interpret data from the study.

11. Use of any other experimental drug or therapy within 28 days of baseline.

12. Known hypersensitivity to thalidomide.

13. The development of erythema nodosum if characterized by a desquamating rash while
taking thalidomide or similar drugs.

14. Any prior use of lenalidomide.

15. Concurrent use of other anti-cancer agents or treatments.

16. Patients with history of deep venous thrombus or pulmonary embolism. Patients who are
at increased risk of thrombosis during treatment with lenalidomide including those
taking concurrent erythropoietin, darbepoetin or high-dose corticosteroids are also
excluded.

17. Patients with a history of embolic events (e.g. TIA) from arrhythmia or peripheral
arterial disease or of recent MI whether or not treated with anti-platelet drugs