Study to Evaluate the Efficacy and Safety of Roxadustat in the Treatment of Anemia in Participants With ESRD on Stable Dialysis

This study will consist of three study periods as follows: 1. Screening Period of up to 6 weeks (8 weeks if on Mircera) 2. Treatment Period: a minimum of 52 weeks, a maximum of up to 3 years from the date last participant is randomized. Minimum study duration for participants enrolled under Protocol Amendment 1 or 2 may be less than 52 weeks 3. A Follow-up period of 4 weeks. Participants will be randomized in a 1:1 ratio to receive either roxadustat or epoetin alfa (active control) in an open-label manner.