* Roche partner Chugai seeks Japan approval for R744
* R744, or Mircera, treats renal anaemia
* Drug was launched outside Japan as Mircera in 2007 (Adds detail, background)
ZURICH, July 22 (Reuters) - Swiss drugmaker Roche Holding AG’s ROG.VX Japanese partner Chugai Pharmaceutical Co (4519.T) said on Wednesday it had filed for approval of its R744 renal anaemia drug with the Japanese health ministry.
Chugai said in a statement clinical trials in Japan showed the efficacy and tolerability of R744 in patients with chronic kidney disease with once-every-four-week intravenous or subcutaneous dosing.
R744 was launched outside Japan in 2007 under the product name Mircera for treatment of renal anaemia, which Chugai said is one of the most frequent complications of chronic kidney disease.
It competes with Amgen Inc’s (AMGN.O) Epogen. A U.S. court last year upheld Amgen’s patents on its blockbuster anaemia drugs, effectively blocking Roche from selling Mircera in the United States. (Reporting by Emma Thomasson, editing by Will Waterman)