Swedish Firm Bactiguard Receives Grant To Develop New Vascular Stents

Bactiguard’s new vascular stents will feature metal coating that won’t kill bacteria, reducing the risk of heart patients getting thrombosis.

Swedish medical device company Bactiguard has won a grant to develop metal-coated vascular stents to reduce the risk of blood clots that may lead to strokes and heart attack.

Traditional vascular stents, which are inserted into the heart to help blood flow better, are mostly coated in materials that kill bacteria.

But this can harm the surrounding tissue, causing infections – something Bactiguard says its own version won’t do.

It is working alongside researchers at Karolinska Institute, a research-led medical university based in Stockholm, on the project and has received 1.5m Swedish krona (£123,000) from Vinnova, the Swedish government agency for innovation systems.

The funding comes from the agency’s Collaborative Project for Better Health fund, which aims to promote sustainable growth in the healthcare and life sciences sector in Sweden, and strengthen international competitiveness.

Professor Staffan Holmin, a senior physician in neuroradiology at the institute’s Karolinska University Hospital and Bactiguard research leader, said: “Stents save lives and are used in both acute care and as a preventive measure of heart infarction and stroke, for example.

“At the same time, the treatment leads to a greatly increased risk of thrombosis formation [blood clotting] in the stent, which is currently managed by prescribing the patient double doses of anti-platelet therapy for several months.

“By coating the stents with Bactiguard’s technology, we hope to reduce the risk of thrombosis in the stent during the acute and subacute phase, and thereby reduce the need for drugs.”

What is Bactiguard’s technology for coating medical devices?
Stents are used when blood vessels in the heart or nervous system need to be widened to allow the blood to pass freely.

They are applied both in acute conditions – a disease with an abrupt onset – and for preventive purposes, such as constrictions of the coronary arteries to avoid heart attacks.

The Bactiguard Infection Protection (BIP) technology consists of a thin layer of noble metals – gold, palladium and silver – which are applied to the surface of a medical device.

Professor Holmin explained it will lead to fewer complications and reduced suffering for the patients, which will make it possible to more safely conduct secondary interventions while the disease is present.

He said: “These secondary interventions are currently associated with great risk because the patient is on blood-thinning drugs, which increases the risk of bleeding.”

How do the vascular stents coated with BIP reduce the number of infections?
Traditional coating technologies often depend on the release of substances that kill bacteria.

But the BIP technology is a non-releasing technology, which means no “good” bacteria is killed and no harm is caused to surrounding tissue.

Cecilia Edström, chief financial officer at Bactiguard, said: “It is a patented technology that can be used to coat medical devices of different types, and coats the right layers so it’s very thin.

“When the device gets introduced to some type of fluids like large urine or other fluids, it creates a galvanic effect.

“Imagine sticking your tongue on a battery or an electrical fence, you don’t want to hold on to it and you let go immediately – that’s what happens to the bacteria, they don’t adhere to the surface and multiply to create biofilm, leading to infections.

“But we don’t kill the bacteria and that’s what makes it different to other technologies – the attachment and formation of the biofilm  is prevented.”

“It’s a non-releasing technology, which means we don’t kill the ‘good’ bacteria and we don’t cause any inflammatory to the surrounding tissue and this is what makes us different from other technologies.”

The release of high amounts of ions or antibiotics that kill the internal bacteria in traditional methods might be effective in reducing infections, but it may also risk and harm the surrounding tissue – resulting in the increase of infection risks.

It could also trigger reactions to the blood, which may lead to thrombosis in a blood vessel and other activation to the blood.

After the procedure using Bactiguard’s technology, the patient receives high doses and combinations of drugs that suppress platelet activation – the process that leads to thrombus formation – which in turn increases the bleeding tendency.

The stent consists of metal wires where platelets – a small cell fragment found in large numbers in blood and involved in clotting – attach within minutes of the procedure, with the risk of thrombosis forming and leading to serious complications such as heart attack or stroke.

The thrombi being formed in the stent can also detach, travel with the blood stream and cause vessel occlusion that may lead to infarctions – tissue death.

After six to 12 months, the surrounding tissue covers the stent and the risk of thrombosis decreases.

Ms Edström added: “What we want to test for in this project is the real indication that the coating in itself reduces the incidences of thrombosis.

“At least we currently know it doesn’t increase the presence of thrombosis when you introduce the device in to the bloodstream.

“We’ve done the initial testing and now we’ll be going into more advanced testing to study both efficacy and safety of the method.” – Compelo