Dimerix hits 70pc recruitment milestone in rare kidney disease drug trial

• Dimerix reports 200 adult patients now randomised and dosed in ACTION3 phase III trial in FSGS patients
• Number represents ~70% of adult patients to be dosed in the pivotal two-year trial
• Patients recruitment remains on track to complete dosing of all 286 adult patients in H2 CY25

Special Report:  Late-stage clinical biotech Dimerix has reached 70% of the total adult patients to be dosed in its ACTION3 phase III clinical trial of lead drug candidate DMX-200 in patients with focal segmental glomerulosclerosis (FSGS).

In an update on the pivotal trial Dimerix Limited (ASX:DXB) said 200 adult patients – out of a total recruitment target of ~286 – have now been recruited and dosed in the trial.

Dimerix emphasised this represents a significant milestone, adding that, based on anticipated recruitment rates at each site, full recruitment of patients into the trial is on track to complete in H2 CY2525.

The trial has also successfully passed six reviews of the trial safety data by the Independent Data Monitoring Committee (IDMC).

Global trial addressing unmet medical need

Titled Angiotensin II Type 1 Receptor (AT1R) & Chemokine Receptor 2 (CCR2) targets for Inflammatory Nephrosis, or ACTION3 for short, Dimerix’s phase III trial is a multi-centre, randomised, double-blind, placebo-controlled study.

The trial has now activated more than 190 clinical sites in 22 countries, with positive feedback coming in so far from the trial sites with regards to patient participation.

In early 2024 Dimerix reported positive interim results from ACTION3 showing DMX-200 was performing better than placebo in reducing proteinuria with no safety concerns to date.

A further blinded analysis is planned once revised primary and secondary endpoints are pre-specified in the trial protocol and agreed upon with the US Food and Drug Administration (FDA).

The regulator confirmed that a proteinuria-based endpoint could be the basis for full marketing approval of DMX-200 in the US following a Type C meeting held in March 2025.

FSGS is a serious kidney disease that causes progressive scarring, leading to permanent damage and, ultimately, end-stage kidney failure often requiring dialysis or a transplant.

It affects adults and children, with no treatments currently approved specifically for this condition anywhere in the world – which obviously has an impact on overall prognosis.

DMX-200 has received orphan drug designation in both the US and Europe, along with the UK’s equivalent designation under the Innovative Licensing and Access Pathway (ILAP).

Patients now entering open-label extension study

A total of 43 patients have now also completed the full two-year ACTION3 study treatment period and have subsequently entered Dimerix’s open label extension study.

“The opening of so many sites across the world and the recruitment of patients into our Phase 3 clinical trial in this rare type of kidney disease has been phenomenal,” CEO and managing director Dr Nina Webster said.

“I am extremely grateful for the dedication and hard work of our clinical team and the investigators at the trial sites, as well as the bravery of the patients and their families.

“We are also pleased to see so many patients rollover into the company’s open label extension study.

She said the next few months were “extremely exciting for the company” as it approached the final stages of patient recruitment in the trial.

Dimerix is also continuing to focus on recruitment into the ACTION3 Phase 3 clinical trial of both adults and paediatric patients, as well as licensing opportunities with potential partners in territories not already licensed.

The company now has four regional licensing deals executed for DMX-200. Collectively, the deals provided up to ~$1.4bn in total upfront payments and potential milestone payments, plus royalties on net sales.

This article was developed in collaboration with Dimerix, a Stockhead advertiser at the time of publishing.

This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.