New data for Roche’s anaemia drug Mircera confirm that the drug can raise haemoglobin levels in the blood with twice-monthly dosing, suggesting it will mount a strong challenge to current treatments should it reach the market.

Two clinical trials of Mircera (Continuous Erythropoietin Receptor Activator) in chronic kidney disease patients – ARCTOS and AMICUS – compared the drug to treatment with Amgen’s rival erythropoietin treatments Aranesp (darbepoetin alfa) and Epogen (epoetin alfa), as well as Roche’s own NeoRecormon (epoetin beta) product.

They found that in patients with anaemia caused by chronic kidney disease, regardless of whether they were on dialysis, Mircera was as good as the competitor drugs in elevating haemoglobin levels, with fewer patients (12% versus 33% of the Aranesp-treated group) seeing their haemoglobin levels rise above the upper recommended limit.

In the studies, twice-monthly or monthly Mircera was compared to either a weekly dose of Aranesp (ARCTOS) or epoetin alfa or beta (AMICUS) dosed between one and three times a week. Roche has filed its drug for approval in both the USA and Europe based on this dosing regimen.

For its part, Amgen has developed a monthly Aranesp formulation that has been submitted for approval and could keep it on level terms with Mircera in the dosing, but the company suffered a setback last month after the US Food and Drug Administration (FDA) asked for another clinical trial before it would consider approval.

Meanwhile, in a bid to defend its franchise, Amgen is suing Roche for patent infringement in a trial due to come to court in September next year. And it has also signed a deal with Fresenius, the largest supplier of dialysis in the USA, to act as sole supplier of erythropoietin products for a period of five years, closing Roche out of that portion of the market.

Aranesp and Epogen are critical products for Amgen, brining in $1.31 billion and $1.22 billion, respectively, in the first six months of this year.