Nanopatches that can be self-administered – and even put in the post – could transform infectious disease prevention.
The "nanopatch" is about a square centimetre in size, it administers a minute, needle-free vaccine dose to a person's skin, dramatically reduces costs and needs neither to be administered by trained medical staff nor to be refrigerated.
But Professor Mark Kendall, a former Oxford rocket scientist turned bioengineer at the University of Queensland in Australia, is cautious about the prospects for what many are hoping could revolutionise infectious disease prevention in developing countries, where around 17 million people die from avoidable diseases each year.
"It has many advantages. It is pain-free, very low cost and could be self-administered. It could be posted to people as it needs no skill to administer. Where [some vaccines] cost $50 (£31) each, this could reduce the cost to $1," he says.
The traditional syringe and needle vaccination, which has barely changed since it was invented in 1853, has big disadvantages, he says. It injects the vaccine into the muscle, which has few immune cells; it needs a relatively large shot of vaccine, and it poses problems with needle contamination and disposal.
So far, his research team has tested vaccine patches against influenza, human papillomavirus (HPV) and even malaria on mice. "The patch uses an applicator to place a very small dose of vaccine directly on the skin where immune cells are most abundant. We do not understand fully why it works so well [but] we do know it works fantastically well on animals. If we can translate that to humans … it could potentially change the world of vaccinations. But we still have a very long way to go," he says.
The great hope is that in the event of a pandemic, these patches could be posted to thousands or even millions of people because they don't need refrigeration and can be self-administered.
Kendall has just returned from Papua New Guinea (PNG), which has the highest incidence of HPV – a virus that can lead to cervical cancer, which is a leading cause of death in young women in developing countries. He took three prototypes of the patch and these were given to local healthcare workers to apply to hospital patients.
The success of the trials means the team may be able to fasttrack full clinical trials on humans next year, Kendall says. The first would be carried out in his home city of Brisbane, followed up in PNG. Even so, he says, it could take 10 years before the nanopatch is on the market.
Kendall, whose team has a three-year research contract with drug company Merck, has been awarded $100,000 by Rolex, specifically to enable poorer countries to take advantage of the development at the same time as wealthier countries. "The natural pattern of a development like this would be to concentrate on developed countries, with developing countries eventually seeing it. The award means we can work on them both in parallel," he says.