Argenica Therapeutics (ASX:AGN) completes final FDA requested assay for ARG-007

Argenica Therapeutics has cleared the final regulatory hurdle required to progress its lead neuroprotective therapy, ARG-007 (xaranetide), toward human clinical trials in the United States.

The company announced that it successfully completed a GLP-compliant hERG assay, addressing the last outstanding FDA clinical hold requirement.

Highlights

• ARG-007 (xaranetide) completed the third and final FDA requested safety assay
• GLP-compliant hERG study showed no statistically significant inhibition of the hERG cardiac potassium channel at the highest testable concentration.
• All three FDA-requested safety assays now demonstrate favourable profiles.
• Phase 2b clinical protocol is expected to be finalised in the coming weeks.
• Argenica plans to submit a comprehensive response to the FDA clinical hold following protocol finalisation.
• Successful FDA review would enable the commencement of clinical studies in the US.

The FDA previously issued a clinical hold on ARG-007 due to insufficient in vitro safety data, specifically requesting three studies before permitting human trials, with the hERG assay addressing cardiac safety and complementing the previously completed TNK and genotox assays.

The hERG channel is a critical component of cardiac electrical activity, and inhibition of this channel by drug compounds has been historically associated with potentially life-threatening arrhythmias, making a robust evaluation of hERG interactions a regulatory requirement before clinical studies can proceed.

In the GLP hERG assay conducted by Switzerland-based B’SYS GmbH, ARG-007 at 1 µg/mL produced a remaining hERG current amplitude of 100.74 ± 1.44%, effectively maintaining baseline channel activity, with statistical analysis confirming no significant difference from the vehicle control (96.48 ± 1.02%, P = 0.0524).

Less than 30% inhibition at the highest concentration meant no IC50 could be determined within the assay range, indicating very low cardiac liability.

Argenica Managing Director Dr Liz Dallimore stated,

“The FDA specifically identified the absence of a hERG study as a deficiency preventing clinical progression, and we have now addressed that requirement with a clean, fully GLP-compliant result showing essentially no cardiac liability at the highest testable concentration.”

The assay followed FDA ICH S7B guideline requirements, using whole-cell patch-clamp methodology on CHO cells expressing the hERG channel at near-physiological temperature.

The assay’s validity was confirmed using the positive control compound moxifloxacin, which produced the expected concentration-dependent inhibition.

With the Phase 2b protocol expected to be finalised shortly, Argenica plans to compile a comprehensive response to the FDA clinical hold, including an updated investigational brochure and protocol focusing on moderate to severe stroke patients, and once the clinical hold is lifted, the IND would be reinstated, enabling ARG-007 to progress into human trials.

The announcement represents the completion of a clearly defined regulatory requirement rather than a clinical efficacy milestone.

The next material development for investors will be the FDA’s assessment of Argenica’s submission and the potential lifting of the clinical hold, which would allow the company to initiate clinical studies of ARG-007 (xaranetide) in the United States.