A randomized double-blind placebo-controlled clinical trial of a multi-target therapeutic against primary age-related feline sarcopenia: PURR-001

Abstract: Primary age-related sarcopenia is a common cause of muscle loss in elderly cats, yet no pharmaceutical treatment has previously been reported. We conducted a randomized, double-blind, placebo-controlled clinical trial to evaluate the efficacy and safety of PURR-001, a once-weekly oral multi-target therapeutic designed to modulate conserved aging pathways implicated in skeletal muscle decline. Thirty-five client-owned and shelter elderly sarcopenic cats were randomized to receive PURR-001 or placebo capsules for 12 weeks. Changes in body mass and ultrasonographic epaxial muscle height were evaluated, while serum biochemistry and adverse events were monitored to assess safety. Exploratory PBMC transcriptomic profiling was performed using Oxford Nanopore cDNA sequencing. PURR-001 treatment resulted in significantly greater increase in body mass than placebo-treated cats (7.40% vs 1.14%) and larger epaxial muscle height increase (22.75% vs 9.00%). A positive relationship between epaxial muscle increases and body mass increase was observed (R² = 0.48). Serum biochemical parameters remained stable throughout the study, with no evidence of clinically meaningful treatment-related toxicity or excess adverse events. Several negative events in both the placebo and treatment group were attributed to pre-existing conditions by the veterinarian teams. This is the first randomized placebo-controlled clinical trial to demonstrate the efficacy of a pharmaceutical intervention for primary age-related sarcopenia in cats, providing a foundation for larger confirmatory studies of gerotherapeutic interventions in companion animals.