Colorectal Cancer Drug May Slow Progress of Multiple Myeloma

Blood cancer experts at UC want to determine whether suppressing a certain growth protein can slow the progression of multiple myeloma, an incurable cancer that claims more than 11,000 lives each year.

Led by Rami Komrokji, MD, director of UC’s leukemia and lymphoma unit, the exploratory study will test the effectiveness of cetuximab (Erbitux), a targeted (monoclonal) antibody that blocks a protein on the cell surface called the epidermal growth factor receptor (EGFR). Antibodies are immune-system proteins that seek out and destroy specific bacteria and viruses.

By blocking EGFR, which helps cancer cells grow and multiply in the blood, researchers believe they may be able to slow the progression of multiple myeloma.

“This drug is different, because it attacks the ability of the cells to grow and multiply, versus killing an existing tumor,” says Dr. Komrokji. “If we can slow the tumor growth, we can reduce pain and suffering associated with the disease, improving the patients’ quality of life.”

Multiple myeloma affects the plasma cells in bone marrow, the soft, blood-forming tissue that fills bone cavities. Plasma cells develop from a type of white blood cell produced in the bone marrow and play a critical role in fighting off infection and disease.

In multiple myeloma, tumors form in the bone and impair the marrow’s ability to produce enough healthy blood cells to fight off infection. As a result, the body’s resistance to the disease is drastically diminished.

As the cancer cells expand into the bone marrow, they cause bone pain and deterioration. If the growth spreads to the nerves, the disease can cause numbness or even paralysis.

“Plasma cells in healthy immune systems produce different types of antibodies to fight each kind of bacteria or virus that enters the body,” explains Dr. Komrokji. “But in multiple myeloma the cells produce abnormal proteins with a decreased level of normal antibodies, which limits the body’s natural ability to fight dangerous infections.”

He also notes that there is no cure for multiple myeloma, so there is an immediate need for better ways to manage the disease.

This is the first time cetuximab—currently approved by the Food and Drug Administration to treat advanced colon cancer—has been studied in the treatment of multiple myeloma.

Dr. Komrokji will test the drug on about 50 patients who have previously received at least one treatment—chemotherapy, bone marrow transplant or radiotherapy—but show indications of disease progression.

Participants will receive six four-week cycles (24 weeks total) of cetuximab intravenously. After each cycle, blood samples will be collected to determine if the patient is responding positively to treatment.

“Previous studies have shown that EGFR is over-produced in many cancers, and recent studies confirm that it is found on myeloma cells,” says Dr. Komrokji. “This study will tell us if blocking EGFR is a viable means of slowing the progression of multiple myeloma.”

According to the American Cancer Society, about 16,000 people in the United States develop multiple myeloma annually and have an average survival rate of three years. While the disease does not always show symptoms, some of the most common indicators include bone pain in the back and ribs, easy bruising or bleeding, extreme limb weakness and fatigue.

For more information on this clinical trial, which is sponsored by Bristol-Myers Squibb and ImClone, call (513) 584-1160.