A drug approved by the FDA in 2012 to treat a type of cancer called multiple myeloma has dangerous side effects that involve the heart. The drug is called carfilzomib, and it is a proteasome inhibitor now linked to an increased risk of dangerous heart events.
High blood pressure, heart failure, heart attack, stroke, and arrhythmias are all examples of adverse cardiac events (ACEs), which, from a new Abramson Cancer Center study at the University of Pennsylvania, are now associated with multiple myeloma (MM) patients prescribed carfilzomib.
MM is a rare bone marrow cancer currently affecting approximately 100,000 people in the United States. It is a cancer of plasma cells; as part of the immune system, plasma cells make antibodies during an infection to fight pathogens. Alongside MM is usually anemia, kidney failure, and recurrent infections. Chemotherapy and radiation are common treatments for this type of cancer as well as, in recent years, proteasome inhibitors like carfilzomib,one of three FDA-approved proteasome inhibitor drugs.
Proteasome inhibitor drugs work by targeting and destroying proteins within a cell. Cancers like MM rely on proteins to survive. However, healthy cells need proteins too.
"Like any cancer therapy, the concern with this approach is that it may have an effect on an otherwise healthy part of the body - in this case, the heart," explained lead author Adam J. Waxman, MD.
The new study analyzed data from 24 other studies from the past decade, including 2,594 MM patients in total. Researchers like Waxman compared the effects on each patient’s heart between carfilzomib and a similar drug, bortezomib. Patients taking bortezomib were much less likely to experience ACEs, severe or mild. But 18 percent of MM patients who were prescribed carfilzomib experienced ACEs, and eight percent of MM patients experienced severe ACEs.
The most common ACE experienced by carfilzomib-taking MM patients was hypertension, followed by heart failure, arrhythmias, and other dangerous conditions. Plus, higher doses of carfilzomib were associated with higher rates of ACEs.
“Anyone who is treating patients with this drug needs to be aware that this is a common event," Waxman said.
Future studies will be done in attempt to determine the specific explanation behind the connection between carfilzomib and risk of ACEs. Especially considering that MM and heart disease share several risk factors, such as older age and obesity, researchers from the study suggest that, meanwhile, MM patients with existing risk factors for both conditions should be on a drug other than carfilzomib.
The present study was published in the journal JAMA Oncology.