The primary purpose of the study is to determine the safety and efficacy and to generate PK and biomarker data for the combination of Pomalidomide and low-dose Dexamethasone in patients with relapsed or refractory multiple myeloma, with moderate or severe renal impairment.

The study will consist of a Screening phase within 28 days prior to cycle 1 day 1. Subjects once enrolled will enter the Treatment phase, in which patients will be treated until progression, or study discontinuation due to other reasons. Subjects will enter the long term Follow-up phase of the study where data will be collected every 3 months for up to 5 years on Secondary primary malignancies, survival, subsequent anti myeloma treatments and date of progression. Subjects will be recruited into one of 3 cohorts depending on the severity of their renal impairment.

Inclusion Criteria:

- Subjects must satisfy the following criteria to be enrolled in the study.

1. Subjects must have documented diagnosis of multiple myeloma and have measurable disease (serum M-protein ≥ 0.5 g/dL or urine M-protein ≥ 200 mg/24 hours).

5. Subjects must have had at least 1 prior antimyeloma regimen including lenalidomide and documented progression as per the International Myeloma Working Group uniform response criteria (Durie, 2006) during or after the last antimyeloma regimen. Induction therapy followed by Autologous Stem Cell Transplant and consolidation/ maintenance will be considered as one regimen.

6. Subjects must have an impaired renal function with an estimated Glomerular Filtrate Rate of < 45 mL/min/1.73 m2 according to the modification of diet in renal disease equation.

1. Impaired renal function must be due to multiple myeloma which needs to be confirmed by kidney biopsy.
2. Subjects may have acute myeloma related renal failure or chronic myeloma related renal failure; they may also have been treated with dialysis before, including dialysis with high cut off membranes.

Exclusion Criteria:

The presence of any of the following will exclude a subject from enrollment

1. Any significant medical condition, laboratory abnormality, or psychiatric illness that would prevent the subject from participating in the study.

2. Any condition including the presence of laboratory abnormalities, which places the subject at unacceptable risk if he/she were to participate in the study.

3. Renal insufficiency due to other reasons than multiple myeloma or due to hypocalcaemia only.

4. Prior history of malignancies, other than MM, unless the subject has been free of the disease for ≥ 5 years; exceptions include the following:

   1. Basal or squamous cell carcinoma of the skin
   2. Carcinoma in situ of the cervix or breast
   3. Incidental histological finding of prostate cancer (Tumour lymphNode Metastasis stage of T1a or T1b)

6. Previous therapy with pomalidomide. 7. Hypersensitivity to thalidomide, lenalidomide, or dexamethasone (this includes ≥ Grade 3 rash during prior thalidomide or lenalidomide therapy).

10. Subjects who are planning for or who are eligible for stem cell transplant.