DMX-200 Milestone: Dimerix Reaches Full Adult Enrollment in Critical FSGS Treatment Study

Dimerix has achieved a significant clinical milestone by completing its adult patient enrollment phase for the ACTION3 pivotal trial evaluating DMX-200 as a potential treatment for focal segmental glomerulosclerosis (FSGS). The company has successfully recruited and dosed all 286 adult participants in this landmark Phase 3 study, representing a crucial advancement in addressing a serious kidney disease with limited therapeutic options.

Understanding the Clinical Challenge

Focal segmental glomerulosclerosis represents a progressive kidney condition defined by scarring within the nephrons’ filtration apparatus. This pathological process typically manifests through elevated protein excretion in urine and progressively compromises renal function, ultimately necessitating dialysis or kidney transplantation for many patients. The limited availability of effective treatment modalities underscores the clinical importance of DMX-200’s development trajectory.

Trial Design and Treatment Protocol

The ACTION3 investigation employs a rigorous double-blind, placebo-controlled framework across multiple medical centers. Adult participants receive either DMX-200 (administered as 120 mg capsules twice daily) supplementing standard angiotensin II receptor blocker therapy, or placebo alone, over a 24-month intervention window. The study’s primary outcome measures focus on quantifying reductions in proteinuria levels and assessing the preservation trajectory of kidney function through eGFR slope calculations.

Enrollment Progress and Safety Profile

Among the 286 dosed adult participants, 69 individuals have concluded the complete two-year treatment phase. Notably, 65 of these completed patients—representing a 94% enrollment rate—have voluntarily transitioned into the open-label extension component of the study. The trial has maintained an excellent safety record, successfully navigating seven independent Data Monitoring Committee evaluations without triggering protocol modifications or emerging safety signals.

Expansion Plans and Regulatory Pathway

Dimerix continues recruiting pediatric patients as a distinct study cohort. Should this pediatric cohort demonstrate efficacy, the pathway would enable DMX-200 application expansion to adolescent populations across priority markets. Building upon validation from the PARASOL collaboration—a worldwide initiative establishing proteinuria as a validated surrogate measure—Dimerix and its U.S. collaborator Amicus Therapeutics plan to engage FDA consultation regarding the proposed ACTION3 endpoints prior to executing the blinded efficacy analysis.

Financial Position and Market Performance

The company maintains robust financial reserves supporting continued ACTION3 operations and enabling evaluation of emerging R&D opportunities. Dimerix shares (DXB.AX) closed trading at AU$0.60, reflecting a 0.83% increase, with the stock fluctuating between AU$0.30 and AU$0.78 throughout the preceding twelve-month period.