Epoetin treatment: what are the arguments to expect a beneficial effect on renal disease progression?

Progression of chronic kidney disease is usually a relentless process. It is initially induced by the underlying kidney disease and its consequences. But, when nephron numbers decrease beyond a certain threshold, it is also caused by deleterious effects of this reduction in nephron number, which creates a vicious circle. Besides treatment of the underlying renal disease whenever possible, the main therapeutic tools that are available to slow the progression of renal failure are optimal control of blood pressure, use of angiotensinconverting enzyme inhibitors, and to a lesser extent dietary protein restriction (reviewed in w1x). The efficacy of these therapies is, however, limited, and the need for other treatments is highlighted by the observation that, for the past decade, the incidence of end-stage renal disease has been increasing at an annual rate of about 6–8% in most European countries. Among the other therapeutic interventions that could slow the progression of renal failure is correction of anaemia through administration of epoetin. Its potential usefulness is suggested by analysis of the pathophysiological mechanisms underlying progression of renal failure and by a few clinical studies.