Maze Therapeutics (MAZE) investor relations material

Study overview and design

• Phase II HORIZON trial was an open-label, basket design evaluating MZE829 in adults with APOL1-mediated kidney disease (AMKD), including diabetic, non-diabetic, and FSGS subgroups, all with high-risk APOL1 genotypes.

• 15 patients were enrolled (8 non-diabetics, 7 diabetics), with 12 included in the efficacy analysis; all were on stable standard-of-care regimens for at least 8 weeks prior to study entry.

• Baseline characteristics were balanced, with moderate to severe proteinuria and a mean eGFR of 41.9 mL/min/1.73 m².

• Primary endpoints were safety and tolerability; secondary endpoints included pharmacokinetics and reduction in proteinuria (uACR).

Key efficacy results

• MZE829 achieved a 36% mean reduction in uACR at 12 weeks across all AMKD patients, with a 50% response rate (≥30% reduction).

• FSGS patients saw a 61.8% mean reduction in uACR; non-diabetic AMKD patients had a 48.6–49% mean reduction and a 57% response rate.

• Diabetic AMKD patients showed early promising results, with two out of five achieving at least a 30% reduction in uACR (individual reductions of 47% and 35%).

• Mean urine protein-to-creatinine ratio (uPCR) reduction was 31% overall, 46% in non-diabetics, and 59% in the FSGS subset.

Safety and tolerability

• MZE829 was well-tolerated with no serious or severe treatment-related adverse events; all treatment-related AEs were mild or moderate.

• Most common adverse events were headache and diarrhea; one patient discontinued due to mild nausea but was included in analysis.

• No clinically relevant changes in vital signs, labs, or ECGs were observed.