Starpharma (ASX:SPL) has moved a step closer to the clinic for its HER2-targeting radiotherapy candidate after securing alignment from the US Food and Drug Administration on the design and development pathway for its first-in-human study.
The Melbourne-based biotechnology company confirmed that a recent Type C meeting with the regulator received positive feedback on both the proposed phase 1 trial design and the broader clinical strategy for DEP HER2, a dendrimer-based radioligand therapy for difficult-to-treat cancers.
The candidate is being developed for patients with locally advanced or metastatic HER2-expressing cancers, including gastric and gastro-oesophageal junction tumours, particularly those who have already exhausted available HER2-targeted therapies. In that setting, the FDA acknowledged a significant unmet medical need, opening the door to potential accelerated development pathways, including Fast Track designation.
The planned study will begin in Europe and enrol up to 15 patients, focusing on safety and tolerability, the drug’s pharmacokinetic and biodistribution profiles, and organ radiation dosimetry. Importantly for the company’s longer-term ambitions, the FDA indicated that data generated outside the United States, combined with the existing preclinical package, should be sufficient to support a future investigational new drug application and enable US-based trials.
The agency also provided detailed guidance on chemistry, manufacturing and controls, effectively endorsing Starpharma’s approach to producing and characterising its dendrimer-based radiopharmaceutical platform. That validation extends beyond a single asset and reinforces the broader clinical and commercial potential of the company’s delivery technology.
Expert input into the regulatory engagement came from Professor Tony Lahoutte, who supported the clinical development strategy and participated directly in discussions with the FDA. He said, “The FDA’s feedback provides important confirmation that Starpharma’s first-in-human phase 1 design and overall clinical strategy for DEP HER2 are in line with regulatory expectations. From a nuclear medicine and radiopharmaceutical perspective, the proposed approach to patient selection, dosimetry and safety evaluation is appropriate. DEP HER2 combines a HER2-targeting moiety with Starpharma’s novel, dendrimer-based delivery platform. The planned clinical study is well-positioned to demonstrate the benefit of the dendrimer technology in targeted radioligand therapy, and to support further clinical development of the product for this high unmet-need population with HER2-expressing cancers.”
Starpharma Chief Executive Cheryl Maley framed the milestone as both regulatory validation and a strategic inflection for the company’s platform.
“DEP HER2 is a key strategic asset for Starpharma, supported by comprehensive preclinical data and a clinically validated platform technology. We are particularly excited by the encouraging data generated to date, which have shown important benefits in targeted delivery for radiotherapeutics.
“This FDA feedback is an important milestone, providing regulatory clarity and validation for the proposed clinical development pathway and marking the exciting transition from preclinical to clinical development. The guidance provides confidence that our current preclinical package, together with the data generated in the forthcoming first-in-patient study, would support a subsequent IND application and clinical development in the US.
“By exemplifying the value of DEP® technology in the high-growth area of radiotherapy in a clinical setting, Starpharma aims to broaden the therapeutic applications and commercial opportunities of its dendrimer platform, whilst continuing to deliver meaningful outcomes for patients.”