EPREX, a version of the human recombinant "erythropoietin", a genetically engineered drug, has recently been found to cause a potentially life-threatening anaemia among patients who have been administered with this drug. This drug introduced in the late 1980s and is used to treat patients with kidney disease. The disease, called Pure Red Cell Aphasia or PRCA usually occurs in vanishingly small number of people and patients affected with this disease need regular blood transfusions. PRCA, though linked to disease of the thymus gland, some viruses and other auto-immune diseases, has never been linked to kidney diseases or drugs used to treat it, till recently.
A special session on the problem was chaired by Dr. Richard Glassock, a kidney specialist at the annual meeting of the American Society of Nephrology, who stated that there have been more than 150 cases of PRCA, which indicates a hundredfold increase over the usual rate. It has also been found that almost all patients who were attacked by this disease were those who were injected the drug under the skin rather than into a vein. However the reason as to why this is happening is not very clear. The German medical professor Eberhard Ritz, who co-chaired the session, said that the answer to this mystery lies in the way Eprex is formulated and not in the drug itself.French physician Jerome Rossert, one of the first to report this mystery says, its link to method of injection is puzzling, since the number of PRCA cases in France is 33 while Germany reported only 3 cases, in spite of both nations have almost the same no. of kidney patients who inject the drug under the skin. He was however convinced about the safety of human recombinant erythropoietin, though he recommended caution in the use of biotech drugs. The disease, says Dr. Glassock,though debilitating, is curable through a kidney transplant.
