This observational, multi-center, open-label, prospective study will evaluate the relationship between serum interleukin-6 (IL-6) and C-reactive protein (CRP) levels and methoxy polyethylene glycol-epoetin beta dosage in participants with chronic kidney disease (CKD) on dialysis. Participants will be recruited who are on stable methoxy polyethylene glycol-epoetin beta maintenance therapy or will initiate therapy with methoxy polyethylene glycol-epoetin beta.