Dimerix Limited has completed dosing of the last adult patient in its ACTION3 Phase 3 trial for DMX-200, exceeding its recruitment target and setting the stage for key regulatory milestones.
- 333 adult patients dosed, surpassing target of 286
- Pediatric cohort recruitment ongoing as separate group
- Trial spans 21 countries with multi-centre, placebo-controlled design
- Positive interim analysis showed DMX-200 reduced proteinuria
- Final data expected by March 2028, supporting regulatory submission
Clinical Milestone Achieved
Dimerix Limited (ASX:DXB) has announced a significant milestone in its clinical development program for DMX-200, a novel therapy targeting focal segmental glomerulosclerosis (FSGS), a rare and serious kidney disease. The company has completed dosing the last adult patient in its ACTION3 Phase 3 trial, enrolling 333 adults, well above the original target of 286. This over-recruitment is expected to enhance the statistical power of the study’s endpoints.
Trial Design and Scope
The ACTION3 trial is a pivotal, multi-centre, randomised, double-blind, placebo-controlled study conducted across 219 sites in 21 countries, including major regions such as the US, Europe, and Asia-Pacific. Patients with FSGS, who are already on stable doses of angiotensin II receptor blockers (ARBs), receive either DMX-200 or placebo over a two-year period. The study aims to assess DMX-200’s efficacy in reducing proteinuria, a key marker of kidney disease progression, and preserving kidney function.
Positive Interim Signals and Ongoing Pediatric Recruitment
Earlier interim analysis from March 2024 demonstrated encouraging results, with DMX-200 outperforming placebo in reducing proteinuria among the first 72 patients randomised. While adult recruitment has now closed, the trial continues to enrol paediatric patients as an independent cohort, reflecting regulatory agreements and the company’s commitment to addressing FSGS across age groups.
Regulatory and Commercial Outlook
Dimerix is preparing for the next phase of its regulatory strategy, including a blinded statistical powering analysis aligned with FDA guidance. The company is also actively pursuing licensing partnerships in territories not yet covered by existing agreements. With patent protections extending potentially to 2045 and orphan drug designations secured in multiple regions, DMX-200 is positioned as a promising candidate in an area of high unmet medical need.
Looking Ahead
The full two-year treatment period for the last dosed patient is expected to conclude in March 2028, marking a critical data readout point. The company’s CEO, Dr Nina Webster, highlighted the importance of this milestone in advancing toward regulatory submission and potential commercialisation, while expressing gratitude to patients and families involved in the trial.
Bottom Line?
With adult recruitment complete and over-enrolled, Dimerix is poised for pivotal data that could reshape FSGS treatment.
Questions in the middle?
- How will the over-recruitment impact the statistical robustness and regulatory review?
- What progress is being made in the paediatric cohort and its potential implications?
- When can investors expect detailed interim and final efficacy data releases?