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No-needle flu vaccine on the way

image of nebuliser

Photo credit: RMIT

Professor Leslie Yeo

RMIT University | 2016 | $531,989

19 separate influenza strains have emerged in humans during the past century, including seven in the past five years alone1

With the risk of a human pandemic on the rise, research into new and better methods of delivering the influenza vaccine couldn’t come soon enough.

Professor Leslie Yeo and his team at the Micro/Nanomedical Research Centre at RMIT University are on their way to revolutionising how vaccinations are delivered by developing a portable device—using a DNA-based flu vaccination that you inhale—and that will mean no more needles!

The team have received an NHMRC Development Grant to test the effectiveness of the vaccine through a next generation nebulisation device. Current devices are large and use ultrasound or compressed air to generate a mist of droplets. Although this works well for small molecules, larger molecules—such as DNA—tend to break apart.

Revolutionary device

This type of NHMRC grant provides financial support to individual researchers and/or research teams to undertake health and medical research at the proof-of-concept stage that specifically drives towards a commercial outcome within a foreseeable timeframe. It also supports commercial development of a product, process, procedure or service that, if applied, would result in improved health care, disease prevention or provide health cost savings.

Professor Yeo’s device uses a piezoelectric material that converts electrical energy into a mechanical motion. In this instance there are tiny finger-like electrodes on the surface of the device that move back and forth.

‘This causes a nano earthquake and in a similar way to an ocean on top of an earthquake it’s going to create a micro tsunami,’ Professor Yeo explained.

‘This nano earthquake is moving back and forth with an incredible amount of acceleration—ten million g-forces—causing the micro tsunami to break up into a mist of droplets.

‘Because we are using an alternating field at such high frequency there is no time to pull and stretch the molecule apart as it is taken up in the aerosol droplets.

‘We have already shown that we can get the vaccine into the deep lung of sheep. The problem with sheep is that they are not an appropriate disease model for flu. The gold standard for testing the flu vaccination is on ferrets, which is what we are currently testing on.’

If you have a low-cost, small, convenient and comfortable method for delivering vaccines—particularly in developing countries—then you can greatly improve patient compliance

What makes this device revolutionary is that when coupled with a DNA-based vaccination it then doesn’t require refrigeration and can be produced at a much faster rate than protein-based vaccines—meaning a more rapid response to pandemics can be achieved. The device is not just small and portable for personalised use, but also delivers the vaccine directly to the site of infection—in the lungs.

‘If you have a low-cost, small, convenient and comfortable method for delivering vaccines—particularly in developing countries—then you can greatly improve patient comfort and convenience, which, in turn, increases compliance,’ he said.

Epidemic response 

Professor Raina MacIntyre, director of the UNSW-led NHMRC Centre for Research Excellence in Integrated Systems for Epidemic Response, said a pandemic similar to the Spanish flu was ‘very possible’—the unprecedented rise in new strains appeared to be a true increase and not just a matter of more cases being detected. 

‘A matched flu vaccine for a pandemic strain of flu takes three to six months—minimum—before we have it for use in the population,’ Professor MacIntyre said.

‘By this time, the epidemic would have already peaked, so we rely on other measures at the start of a pandemic such as antivirals and non-pharmaceutical measures. New technologies that allow rapid vaccine development will enable the use of vaccines for early epidemic control.

It is not just for flu vaccination—this type of nebulisation has the potential to treat many different diseases given that any drug can be nebulised using the device. These could constitute the next generation of biologic therapeutics, including DNA, small RNA, peptides, proteins and even stem cells. 

‘Not only have we created a portable and practical device, we created a platform technology that can be used for many applications,’ he said.

‘We have a particular interest in delivering lung cancer drugs—requiring more precision due to side effects from the drugs. You could have it delivered in the comfort of your home—instead of going to the hospital—and hopefully use a lot less of the expensive lung cancer drugs given it directly targets the disease site,’ he explained.

1Bui, C. M. et al (2017) An overview of the epidemiology and emergence of influenza A infection in humans over time, Archives of Public Health, 75:15 DOI: 10.1186/s13690-017-0182-z