Long-term darbepoetin use is safe and effective for treating anemia in patients with non-dialysis chronic kidney disease (CKD), according to a post-marketing surveillance study conducted in Japan.
The study examined a safety analysis set of 5547 patients and effectiveness analysis set of 5024 patients. All patients were treated with darbepoetin and followed up for 3 years.
In the safety analysis set, adverse events (AEs) and adverse drug reactions (ADRs) occurred in 44.4% and 7.1% of patients, respectively, Tetsuhiro Tanaka, MD, of the University of Tokyo Graduate School of Medicine, and colleagues reported online ahead of print in Clinical and Experimental Nephrology. The 7.1% incidence rate of ADRs was lower than that reported in pre-approval Japanese clinical trials (30.75%), according to the investigators.
Cardiovascular (CV)-related AEs occurred in 12.6% of the overall population. The proportion of patients who presented with CV-related AEs was lower among patients with a higher hemoglobin (Hb) level at the time of occurrence. For example, the proportion of patients with CV-related AEs was 7.1% among those with an Hb level below 11 g/dL at the time of event occurrence compared with 0.2% among those with an Hb leve of 13 g/dL or higher.
The study identified no new safety concerns, Dr Tanaka and colleagues reported.
In the effectiveness set, mean Hb levels remained in the 10.0–10.6 g/dL range during weeks 4–156.
At 3 months after initial darbepoetin administration, the composite renal endpoint of either a 50% reduction in estimated glomerular filtration rate, initiation of dialysis, or renal transplantation occurred in 39.5% of patients with an Hb level of 11 g/dL or higher compared with 44.8% of those with an Hb level below 11 g/dL. An Hb level of 11 g/dL or higher vs less than 11 g/dL at 3 months after darbepoetin initiation was associated with a significant 27% decreased risk of the composite renal endpoint.
The cumulative proportion of renal survival (patients with no composite renal endpoints) was significantly higher among patients with an Hb level of 11 g/dL or higher compared a level below 11 g/dL.
“This study demonstrated that a decrease in composite renal endpoints is associated with the achievement of target Hb levels being maintained by darbepoetin,” the authors wrote.
Tanaka T, Nangaku M, Imai E, et al. Safety and effectiveness of long-term use of darbepoetin alfa in non-dialysis patients with chronic kidney disease: a post-marketing surveillance study in Japan. Clin Exp Nephrol. 2018; published online ahead of print.