Cardiovascular disease is the leading cause of death and disability globally. Most deaths result from vulnerable atherosclerotic plaque, an unstable build-up of fat and other substances in the arterial walls, which ruptures, leading to arterial blockages and heart attacks and strokes.

Traditional approaches rely on treating vulnerable plaques after clinical events or by using systemic therapies to prevent future events and have clear limitations: 

1. suboptimal drug concentrations at the diseased site and exposing the body to unwanted side effects, including bleeding complications from long-term use of antiplatelets;

2. risks of restenosis and thrombosis resulting from stents and balloons which deliver drugs to the vessel surface rather than into the plaque core.

Innovation

Vulnerable plaques can be identified before their rupture. Yet, the final piece of the puzzle in preventing heart attacks and strokes is to deliver drugs directly into plaques to shrink and stabilise them, leaving nothing behind. Our project aims to commercialise the first ever medical device specifically designed to achieve this and overcomes the limitations of current treatments.

The device uses a circumferential array of hollow microneedles on a spring embedded within an angioplasty balloon catheter. When the balloon inflates, the spring-containing-microneedles expands, the microneedles penetrate the vessel wall and deliver drugs uniformly throughout the arterial circumference where they are needed the most. The device then collapses for minimally-invasive removal.

The microneedles are just 100-μm in height and are the smallest metallic hollow microneedles ever reported. This miniaturisation is central to the aim of the device: delivering medicine directly into vulnerable plaques without perforating the vessel.

The device connects to an external drug reservoir, where any type and amount of drug can be delivered. This allows for personalised treatment for each unique patient.

Manufacturability

As part of a current advanced PhD project at RMIT University, we have successfully designed, developed and tested the microneedles produced in a circumferential array. Our tests have involved simulation of the balloon-spring interaction using Abaqus (Dassault Systèmes), mechanical tests of the spring and hollow microneedles, and injection of dyes into an arterial mimic. To produce the prototype components, we used custom raw materials and complex laser equipment. Our next step is to assemble the complete prototype. Our device has been designed to be used in current angioplasty procedures with minimal clinical training for ease of implementation. As we advance the project further, we aim to refine the manufacturing process and establish industry collaborations to minimise production costs. Funds from this contest will be used to purchase materials and equipment booking time to refine our design and prepare for a small batch manufacturing.

Marketability

Almost a million angioplasty procedures are conducted annually in the US alone. Globally, the cardiovascular treatment market size was estimated to be USD 241 billion in 2024, with this number projected to increase in the future with an ageing population. Once commercialised, our product will not only tap into this significant market but also help to alleviate one of the biggest health issues we face today.