Study Says Genetic Tests May Predict if Procrit, Aranesp or Epogen Will Speed Tumor GrowthJun 3, 2008 | Parker Waichman LLP
Some cancer patients treated with the anemia drugs Procrit, Aranesp and Epogen could experience increased tumor growth. However, researcher recently reported that there may be a way to predict which cancer patients are at risk for this devastating side effect.
Procrit, Aranesp and Epogen are known as an erythropoiesis-stimulating agent (ESA). All are made by Amgen, but Procrit is sold by Johnson & Johnson subsidiary Ortho Biotech under a licensing agreement. ESAs are a bioengineered version of a natural protein made in the kidney that stimulates the bone marrow to produce more red blood cells. Over the past 18 months, eight late-stage clinical trials have shown that treatment with ESAs can have an adverse impact on cancer survival.
In March, Amgen and Johnson & Johnson announced that they would be including a black box warning on the drug’s labels about their association with increased tumor growth and shortened survival time in some cancer patients. The latest black box to be included on the labeling of Procrit, Aranesp and Epogen came on the heels of the PREPARE breast cancer study. That breast cancer study was one of 5 clinical trials that Amgen had agreed to after the safety of Aranesp was called into question. The new black box will cite information from PREPARE which showed patients had a higher risk of death on Aranesp. It also notes danger for patients with cervical cancer, based on results in December from a study called GOG-191.
A week later, an FDA advisory panel voted 13 to 1 in favor of allowing the continued sale of the ESAs for use in cancer patients undergoing chemotherapy. However, the panel voted 11 to 2 in recommending that the drugs not be used in cancer patients who are likely to be cured from their treatments, which suggests the drugs should only be used as part of a best-supportive care regimen for patients with advanced cancer or those expected to die from the cancer. The panel also voted 9 to 5 that the shouldn’t be used in patients with breast cancer as well as patients with head and neck cancer.
Sales of the anemia drugs have slumped amid the safety concerns. But on Sunday, researchers from the University of Washington presented a study at the American Society of Clinical Oncology in Chicago that indicated a genetic test may help predict whether giving cancer patients anemia drugs could make their cancer worse. In the study, the research group measured levels of erythropoietin receptor messenger RNA in tumor samples from 101 patients with head and neck cancer who took part in a trial of Aranesp. The aim was to test whether the drug might be acting on tumor blood vessels and other membranes as well as red blood cells.
Among patients treated with radiation therapy alone, without prior surgery, tumors with high-levels of this type of RNA messenger progressed faster in patients who received the anemia drug compared with patients given a placebo. Testing for the RNA messenger gene could allow the anemia drugs to be used in a target way, the researchers said.
However, the researchers emphasized that the findings were preliminary and need to be confirmed with a larger analysis of tumor specimens.