That's when an expert panel will be convened by the US Food and Drug Administration (FDA) to debate the merits of the drugs, manufactured by Amgen.
While it has been suspected for some time that Procrit and Aranesp pose a risk to cancer patients weakened by chemotherapy, this latest study not only appears to confirm what has been suspected, but tips the balance into the danger zone.
Procrit, sold under license from Amgen by Johnson & Johnson, was approved for use in cancer patients in 1993. Aranesp was given the nod in 2002. Both drugs were approved based on a capacity for the reduction of the need for blood transfusions.
However, as is often the case when a drug is studied in an effort to win approval from the FDA, the studies were insufficient in duration and breadth to accurately address a patient's longevity.
Indeed, initially it was believed that the drugs would allow a patient to live longer. A meta-analysis conducted by the Cochrane Collaboration and published in 2004 discerned that patients who were given the drugs tended to live longer.
That no longer appears to be the case, once new data is averaged in. Some of that data came from Cochrane itself, the international research group which found two years later that patients using the drugs carried a higher risk of death by eight per cent. However, the 2006 meta-analysis just missed being statistically accurate.
Still, a trend seemed to be developing. Studies originally designed to show that higher doses would prolong life, actually demonstrated the opposite. As more studies were done and additional data factored in, the results first suggested by the Cochrane study of 2006 were suddenly beginning to achieve statistical significance.
Last year the FDA ordered stronger warning labels after it was found that using the drugs too aggressively posed a risk to cancer patients. Procrit, or Aranesp use could worsen their conditions, or even hasten death.
The latest data, published today by JAMA, serves as a confirmation of what is already known, or suspected.
The question now, is what will the FDA decide when it meets on March 13th?
The latest study, as summarized in this morning's edition of the New York Times, combines data from 51 clinical trials involving 13,611 patients. Although the study also found a 57 per cent increased risk for the development of blood clots in veins, Dr. Charles L. Bennett of Northwestern University and lead author of the study suggests that in his opinion blood clotting was not the foundation for higher risk of death. Rather, in his view, the drugs foster tumor growth.
Procrit and Aranesp are synthetic forms of the natural hormone erythropoietin. Dr. Bennett, an oncologist and hematologist, suggests there is evidence that the drugs directly stimulate the growth and spread of tumors, although Amgen scientists dispute that claim.
If the drugs allegedly prove dangerous in cancer patients when used at dosages higher than what is suggested on product labels, the question remains whether or not the drugs are safe when used at prescribed levels. The FDA will most assuredly be debating that issue on the 13th of next month, along with the potential to restrict their use in certain cancer patients such as patients suffering from breast cancer, or cancers affecting the head or neck.
Another possibility is the delay of treatment until a patient's anemia reaches a more pronounced threshold.
The fact remains, however, that Aranesp and Procrit, according this latest meta analysis, raise the risk of death amongst cancer patients by about 10 per cent, which is cited as statistically significant.
The anemia drug Epogen, manufactured by Amgen and similar to Procrit but aimed at kidney dialysis patients, is not expected to enter into discussions.