• Blinded review confirms ACTION3 study remains >90% powered to demonstrate proteinuria treatment effect
• Proteinuria chosen as primary endpoint to maximize likelihood of successful regulatory approval
• ACTION3 trial recruitment complete, with pediatric cohort ongoing

Dimerix Limited has announced that the blinded review of the ACTION3 Phase 3 study data to confirm the statistical assumptions of the primary endpoint has been successfully completed. The review has confirmed that the ACTION3 study remains appropriately statistically powered (>90%) to demonstrate a treatment effect for the primary study endpoint of proteinuria. This means that if DMX-200 continues to reduce proteinuria in trial patients as anticipated, then there is a >90% chance that the study will successfully show a statistically significant proteinuria treatment effect at the trial's conclusion. In parallel to the blinded review, Dimerix and its commercial partners assessed the evolving landscape for Focal Segmental Glomerulosclerosis (FSGS) and potential endpoints. This analysis, including evidence from the PARASOL working group, FDA feedback, and recent FDA approval of a new FSGS therapy based on the proteinuria endpoint, has led Dimerix to conclude that proteinuria is the most appropriate primary endpoint for the ACTION3 trial to support traditional regulatory approval. The ACTION3 Phase 3 clinical trial adult cohort is fully recruited, with 333 patients, and the last patient is expected to receive their last dose in March 2028. Recruitment of the pediatric patient cohort aged 12-17 years old remains ongoing as an independent cohort in the trial. The trial has previously passed a formal futility analysis and had 7 Independent Data Monitoring Committee reviews without identifying any safety issues or requesting changes to the protocol.Dimerix believes that focusing the ACTION3 trial on the proteinuria endpoint significantly reduces the clinical and commercial risk for traditional regulatory approval, compared to the increased cost, timeline, and probability of success associated with pursuing an accelerated approval pathway based on an eGFR endpoint.

Dimerix remains well positioned to continue focusing on advancing the ACTION3 Phase 3 clinical trial, as well as the advanced licensing discussions with potential partners in territories not already licensed.