BY OUR CORRESPONDENT
18 November,2006: Erythropoetin, the largest selling biotech drug used to address cancer treatment related anaemia is implicated in heart problems that could even lead to even death.
Also known as epoetin or epo, this class of drugs cloaked a sale of $9 billion last year. The leading manufactures are Amgen and Johnson & Johnson.
New finding could mar the glory of these highly popular drugs which are considered the cornerstone of biotherapeutics. Drugs derived through the biotech route are projected as comparatively safer than their chemical counterparts, according to experts.
The study tested anemia in kidney patients who did not yet need dialysis, a mechanical blood-filtering technique used to keep alive patients whose kidneys have almost entirely failed. It divided the patients into two groups. One group received epoetin with a goal of almost fully correcting their anemia, a lack of red blood cells associated with fatigue and shortness of breath.
The others were allowed to remain more anemic and generally received less epoetin. Patients in the first group were 34 percent more likely to die or suffer heart problems than those in the second.
But its findings should apply to patients on dialysis as well, noted Dr Ajay Singh, an associate professor at Harvard Medical School and the study’s lead author.
Nearly one million Americans a year receive prescriptions for the drug, known as epoetin, or darbepoetin, a closely related drug also used in anemia treatment.
In the first nine months of 2006, Amgen sold $4.9 billion of Aranesp (darbopoetin)and Epogen (epoetin), accounting for almost half its revenue. Sales of the two drugs rose almost 15 percent compared with the period in 2005.
Johnson & Johnson, which sells epoetin under the brand names Procrit in the United States and Eprex everywhere else, reported sales of $2.4 billion in the first nine months of 2006, down slightly from 2005, according to reports.
Epoetin, a naturally occurring protein produced mainly in the kidneys, stimulates bone marrow cells to produce hemoglobin, the main component of red blood cells. Darbepoetin, which was introduced in 2001, is a version of epoetin that has been slightly modified so that it does not need to be given as frequently. Both drugs are given via injection.
Since epoetin was approved in 1989, it has become a standard treatment for more than 90 percent of dialysis patients in the United States, and it is increasingly used for patients with earlier-stage kidney disease. The drug is also widely used for cancer patients, who often suffer from anemia as a side effect of chemotherapy. Some cancers can also cause anemia on their own.
Before epoetin, blood transfusions were the only effective treatment for anemia. But transfusions carry a risk of infection and can eventually prevent patients from receiving transplants. For most patients, epoetin appeared a safe alternative.
BY OUR PHARMA CORRESPONDENT