The Use of Darbepoetin to Stimulate Erythropoiesis in the Treatment of Anemia of Chronic Kidney Disease in Dogs

Background: Darbepoetin alfa (darbepoetin) is an erythropoiesis-stimulating agent used for the treatment of anemia secondary to chronic kidney disease (CKD) in dogs, but reports describing response are lacking. Hypothesis/Objectives: To evaluate the effectiveness of darbepoetin in dogs with anemia secondary to CKD, dosing protocols, and adverse events. Animals: Thirty-three client-owned dogs with naturally occurring CKD, including 26 with comorbidities. Methods: Multi-institutional retrospective study. Results: The median starting dosage and highest dosage of darbepoetin administered were 0.5 and 0.8 μg/kg SC once weekly, respectively. Response to treatment was defined as achieving a packed cell volume (PCV) ≥30% or an increase in PCV ≥10%. Twenty-eight of 33 dogs (85%) achieved a PCV ≥30% and 22 of 33 (67%) dogs achieved an increase in PCV ≥10%. Median time to achieve a PCV ≥30% was 29 days. A higher starting dosage was associated with achieving an increase in PCV ≥10% (P =.01). No dog sustained a response at a dosing interval >q21d. Potential adverse events included increased blood pressure requiring treatment (n = 12), seizures (n = 5), vomiting (n = 3), diarrhea (n = 3), and possible pure red cell aplasia (PRCA) (n = 2). Conclusions and Clinical Importance: Darbepoetin, when combined with treatment of comorbidities, is an effective treatment for anemia secondary to CKD in dogs. A dosing interval >q21d was ineffective at maintaining a response to treatment. PRCA was a possible adverse event in 2 of 33 dogs (6%).