This is a clinical trial for adults who have been diagnosed with relapsed or refractory multiple myeloma.
   
The purpose of this study is to assess the tolerability and safety of the investigational combination of daratumumab/pomalidomide/dexamethasone/clarithromycin (D-ClaPd) in patients with relapsed or refractory multiple myeloma. This study aims to determine if the addition of daratumumab to current standard combination treatment of clarithromycin, pomalidomide, and dexamethasone (ClaPd) in early relapsed, previously daratumumab exposed patients will be effective with high response rates.

Investigational means that this combination has not yet been approved by the United States Food and Drug Administration (FDA).   

Pomalidomide is an anticancer drug (called immunomodulatory drug) that works by activating the immune system to fight myeloma cells. It has been used for therapy in multiple myeloma for this purpose. Pomalidomide is administered orally (by mouth).
   
Dexamethasone is a synthetic (man-made) steroid taken by mouth to cause programmed cell death. This means that steroids, such as dexamethasone, can trigger the destruction of plasma cells. Dexamethasone is given via intravenous (IV) infusion. 
   
Clarithromycin is an antibiotic drug that helps treat and prevent bacterial infections but also has been used with dexamethasone to improve its ability to kill myeloma cells. Clarithromycin is administered orally (by mouth).
   
Daratumumab is a monoclonal antibody given via injection that attaches to myeloma cells and tells the immune system to attack them. This action by the body can decrease myeloma cell growth and therefore can prevent tumor growth. Daratumumab is given via subcutaneous injection, just under the skin. 
   
Participants will receive daratumumab/pomalidomide/dexamethasone until disease progression or occurrence of an unacceptable toxicity. Participants will be treated for 8, 28-day cycles. In addition, clarithromycin will be given twice a day until a good response is achieved or up to 8 cycles, whichever occurs first.
   
Following the 8 cycles all responding participants with partial response or better will receive maintenance of daratumumab, pomalidomide, and dexamethasone for up to 24 cycles until progressive disease or unacceptable toxicity.