Dimerix (ASX:DXB) has reached a significant milestone in its late-stage clinical program, announcing that its global ACTION3 Phase 3 trial of DMX-200 for focal segmental glomerulosclerosis (FSGS) has now completed recruitment and dosing of its target 286 adult patients.
The ACTION3 study is a large, multinational, double-blind, placebo-controlled trial evaluating the safety and efficacy of DMX-200 when used in combination with standard-of-care angiotensin II receptor blockers. Patients are treated for two years, during which the trial measures both proteinuria reduction and preservation of kidney function via eGFR slope. Sites across 21 countries contributed to recruitment, including the United States, Europe, the UK, Japan, China and Australia.
Of the 286 adults enrolled, 69 patients have already completed the full treatment period, and 94 per cent of those eligible have opted into the open-label extension study, in which all participants receive DMX-200. The company also confirmed the trial has successfully passed seven independent safety reviews, with no protocol changes required.
The program has shown promising signals along the way. In March 2024, an interim analysis of the first 72 randomised patients demonstrated that DMX-200 was outperforming placebo in reducing proteinuria. Although interim results do not guarantee final outcomes, they contributed to growing confidence in the asset as a potential first-in-class therapy.
Dimerix is now preparing for the next phase of regulatory engagement. Together with its U.S. commercial partner, Amicus Therapeutics, the company will seek FDA feedback on proposed clinical endpoints and the possibility of pursuing accelerated approval. Pediatric recruitment continues in a separate trial arm, which may support future filings in younger populations.
Dimerix CEO and Managing Director Dr Nina Webster said the completion of adult recruitment reflects the company’s operational strength in a complex rare-disease setting. “Achieving this milestone in a rare disease setting reflects our ability to execute efficiently in complex environments. With patient data now being collected across a two-year treatment period, we are progressing toward a number of key value-inflection points,” she said.
FSGS is a serious, progressive condition that leads to scarring of the kidney’s filtering units, proteinuria and eventual kidney failure. With over 40,000 patients affected in the United States alone and no targeted therapies available, the need for new treatment options is widely recognised. Disease progression can be rapid, and even kidney transplantation does not guarantee sustained remission, with recurrence rates reaching up to 60 per cent in some patients.