Adeno‐associated virus‐vectored erythropoietin gene therapy for anemia in cats with chronic kidney disease

Background A treatment of chronic kidney disease (CKD)‐associated anemia in cats is needed. SB‐001 is an adeno‐associated virus‐vectored (AAV)‐based gene therapeutic agent that is administered intramuscularly, causing the expression of feline erythropoietin. Hypothesis/Objective We hypothesized that SB‐001 injection would lead to a sustained increase in PCV in cats with CKD‐associated anemia. Animals Twenty‐three cats with International Renal Interest Society (IRIS) Stage 2 to 4 CKD‐associated anemia were enrolled at 4 veterinary clinics. Methods In a prospective clinical trial, cats were treated with 1 of 3 regimens of SB‐001 (Lo 1.2 × 109 genome copies [GCs] on Day 0; Lo ± Hi [supplemental 2nd dose of 3.65 × 109 GC on Day 42]; Hi 3.65 × 109 GC IM on Day 0) and followed for 70 days. Results A response to SB‐001 at any time between Day 28 and Day 70 was seen in 86% (95% confidence interval 65, 97%) of all cats. There was a significant (P