Biopharmaceutical company Dimerix Limited (ASX: DXB) has advised that the Independent Data Monitoring Committee (IDMC) has confirmed the dose of DMX-200 to be used in adolescent patients aged 12 to 17 years participating in the ACTION3 clinical trial.
This allows recruitment of adolescent patients to begin into the ACTION3 Phase 3 global clinical trial in patients with focal segmental glomerulosclerosis (FSGS). The adolescent approved dose is the same as the 120mg adult dose currently being administered in the ACTION3 Phase 3 trial which is given orally and twice daily.
In making this determination the IDMC reviewed the aggregate interim safety and pharmacokinetic data, including simulations in adolescents, from the adult cohort of the ACTION3 Phase 3 trial taken at the first interim analysis point in March 2024. The IDMC noted “the safety margin [of DMX-200] should allow [the ACTION3 Phase 3] clinical study to proceed in this adolescent population using adult doses”. Approximately 15 specialist paediatric nephrology centres across the UK, USA, Mexico, Brazil and Argentina have been selected to recruit adolescent patients with FSGS.
“The positive recommendation of the IDMC to allow adolescent dosing, further extends the strong safety profile and tolerability of DMX-200 when used in FSGS patients. This is especially important as paediatric FSGS remains an area of high unmet need with limited therapeutic options and a high risk of progression to end-stage kidney disease," Chief Medical Officer, Dr David Fuller, said.
The Phase 3 study, which is titled “Angiotensin II Type 1 Receptor (AT1R) and Chemokine Receptor 2 (CCR2) Targets for Inflammatory Nephrosis”, or ACTION3 for short, is a pivotal (Phase 3), multi-centre, randomised, double-blind, placebo-controlled study of the efficacy and safety of DMX200 in patients with FSGS who are receiving a stable dose of an angiotensin II receptor blocker (ARB). Once the ARB dose is stable, patients will be randomised to receive either DMX200 (120 mg capsule twice daily) or placebo.
The single Phase 3 trial in FSGS patients has interim analysis points built in that are designed to capture evidence of proteinuria and kidney function (eGFR slope) during the trial, aimed at generating sufficient evidence to support marketing approval.
Dimerix is currently focussed on developing its proprietary Phase 3 product candidate DMX-200 (QYTOVRA in some territories), for Focal Segmental Glomerulosclerosis (FSGS) kidney disease, and is also developing DMX-700 for Chronic Obstructive Pulmonary Disease (COPD). DMX-700 and DMX-700 were both identified using Dimerix’ proprietary assay, Receptor Heteromer Investigation Technology (Receptor-HIT), which is a scalable and globally applicable technology platform enabling the understanding of receptor interactions to rapidly screen and identify new drug opportunities.