Shire’s Dynepo (epoetin delta) is effective in controlling anaemia in patients with chronic kidney disease, including those whose disease is the result of diabetes, two late-stage trials presented at the 42nd Annual Meeting of the European Association for the Study of Diabetes (EASD) have shown.
The large-scale Phase III studies revealed that the agent can effectively maintain haemoglobin at target levels (10-12g/dL) over a long period of time (up to 52 weeks) when administered intravenously or subcutaneously, the group said, and added that the data demonstrated overall efficacy in various types of patients with CDK-associated anaemia - whether they were on dialysis or not.
The results are important because diabetic nephropathy is the leading cause of kidney failure in the western world today, and around two million people around the globe are undergoing treatment for end stage renal disease, of which about 77% are on dialysis, according to Shire. Moreover, as anaemia occurs at an earlier stage in patients with diabetic nephropathy - and is often more severe than with other causes of CKD - the need for effective treatments in this patient subset is great.
Dynepo is the first erythropoiesis-stimulating agent (ESA) to be produced by in a human cell line, via activation of the gene which codes for erythropoietin in human cells rather than cloning and transferring these genes into animal cells, the method by which Amgen’s Epogen (epoetin alfa) is produced.
The Phase III studies presented at EASD were actually carried out by Sanofi-Aventis and formed the basis of the drug's approval back in 2002, but this is the first time the results have been put in the public domain, a spokesperson for Shire told PharmaTimes.
After obtaining approval for the treatment of anaemia in patients with chronic renal failure, Sanofi-Aventis decided not to commercialise the agent and transferred rights back to TKT, which Shire bought last year. The spokesman said that Shire intends to go ahead with commercialisation, as it believes that Dynepo can offer advantages over its rivals that are produced in animal cell lines, and says a launch has been pencilled in for early next year.
But last month, a US court of appeal ruled that Dynepo infringes two patents protecting Amgen’s EPO franchise. The company sells two EPO products, Aranesp (darbepoetin alfa) and Epogen, which brought in revenues of $1.31 billion and $1.22 billion, respectively, in the first half of this year. Shire is unlikely to be able to bring its agent to market in the US while the litigation with Amgen drags on.
The situation differs in Europe though, where Amgen does not sell its Epogen product itself. Here the drug is sold under license, as Procrit, by Johnson & Johnson, but TKT won a pivotal legal battle clearing the way for Dynepo's launch in Europe back in 2004.
With regard to the next step in the Dynepo’s clinical programme, Dr Jonathan Kwan, of the South West Thames Renal & Transplantation Unit at St. Helier Hospital, UK, said that Shire is initiating a study to investigate a reduction in the dosing frequency of Dynepo, “because of the increasing trend for less frequent dosing intervals with ESAs." He went on to say that the study will also "evaluate the impact of treatment with Dynepo on diabetic retinopathy which, together with diabetic nephropathy, is a serious complication in diabetes patients.”