Instylla has announced premarket approval (PMA) from the US Food and Drug Administration (FDA) for the company’s flagship product Embrace Hydrogel Embolic System (HES). Embrace HES has been approved for the embolization of hypervascular tumours in peripheral arteries ≤5mm.
Hypervascular tumors (HVTs), which commonly occur in the liver, kidney, bone, and other organs, are characterised by an abnormal increase in blood vessels and are often associated with poor survival outcomes. Their high vascularity can make surgical removal difficult due to the elevated risk of bleeding. For patients with limited progressive disease or for local tumour control, transcatheter arterial embolization (TAE) and transarterial chemoembolization (cTACE) are established and widely used treatment options.
Embrace HES consists of two low-viscosity aqueous liquid precursors that interact to crosslink intravascularly when simultaneously injected into blood vessels during the embolization procedure to form a soft, polyethylene glycol (PEG) hydrogel. This liquid embolic is designed to deeply penetrate the tumor vascular bed, crosslink, and stop blood flow.
Premarket approval for Embrace HES was granted based on results from a prospective, randomised, multicentre pivotal study that evaluated its safety and effectiveness for the embolization of hypervascular tumours compared to the standard of care (TAE or cTACE).
The study enrolled 150 patients with hypervascular tumours across 22 global institutions and randomised them 2:1 to receive either Embrace HES or standard of care treatment. Embrace HES met both primary safety and effectiveness endpoints, demonstrating 88.6% technical success as confirmed by an independent core lab and 99% freedom from major adverse events, as adjudicated by a clinical events committee. Importantly, no adverse events were classified as device-related only.
“The pivotal trial was designed to evaluate the Embrace HES system in patients with hypervascular tumours,” said Nadine Abi-Jaoudeh (University of California, Irvine, USA), national principal investigator of the study. “Embrace HES is the first liquid embolic approved specifically for this indication, with a unique design that enables deep penetration into vessels as small as 10 microns. Delivered as two liquid precursors that polymerise in situ to minimise non-target embolization, the cohesive embolic also avoids catheter entrapment. Additionally, Embrace HES does not have any imaging artifacts, allowing us to assess follow-up imaging with confidence. The trial met both its safety and efficacy endpoints, and I am excited to have this wonderful new tool in the interventional radiology (IR) repertoire.”
“We are incredibly proud to receive FDA approval for Embrace HES, offering a transformational embolic platform technology solving critical unmet needs for cancer patients with hypervascular tumours,” said Sean Boyle, chief executive officer, Instylla. “This milestone represents years of innovation and dedication of our team to advancing interventional oncology. More importantly, it brings new hope to patients and their families facing the challenges of cancer. We are motivated and committed to delivering technically advanced, clinically impactful solutions that empower interventional radiologists and expand therapeutic options across a broad range of vascular conditions.”
