Swedish biopharmaceutical company Calliditas Therapeutics, an Asahi Kasei (TYO:3407) company, announced on Monday that the primary safety endpoints for a Phase 2a, randomised, double-blind, placebo-controlled trial of setanaxib in patients with Alport syndrome, were presented at the American Society of Nephrology Kidney Week in Houston, Texas, on 8 November.

The trial enrolled 20 patients aged 12-40 years with genetically confirmed Alport syndrome, a urine protein-creatinine ratio (UPCR) of 0.8 g/g or higher, and an estimated glomerular filtration rate (eGFR) of at least 30 mL/min/1.73 m2. Subjects were randomised in 2:1 to receive oral setanaxib (800 mg BID [18-40 years]/800 + 400 mg/day [12-17 years], n=13; or placebo, n=7) and background therapy for 24 weeks, with a four-week follow-up period on background therapy alone. The primary endpoints included serious adverse events (SAEs) and adverse events of special interest (AESIs), while secondary endpoints included the change in UPCR and eGFR from baseline.

The primary safety endpoints were met with adverse events occurring at similar frequencies in both treatment groups, and no AESIs were reported.

Patients receiving setanaxib had a 15% mean reduction in UPCR at 24 weeks and a 27% mean reduction in UPCR at four weeks post-dosing compared to placebo. At Week 24, two patients (15.4%) in the setanaxib group achieved a reduction of at least 25% in UPCR from baseline, compared with none in the placebo group. There was a 5% mean reduction in eGFR with setanaxib at 24 weeks and a 4% reduction at four weeks post-dosing versus placebo. Further research is needed to investigate setanaxib's clinical efficacy and confirm its benefit/risk profile in a larger Alport syndrome patient population, Calliditas said.

Professor Daniel Gale of Royal Free Hospital, London, who presented the findings, said: "These findings represent an important step toward establishing the safety of setanaxib in patients with Alport syndrome, an underserved patient group for whom no approved therapies currently exist."

Alport syndrome is a rare genetic kidney disease resulting from mutations in collagen type IV genes that can lead to progressive loss of kidney function and end-stage kidney disease.