Needle phobics rejoice: in the future vaccines may be delivered via nanopatches, tiny material patches already being trialled in Papa New Guinea.
The drug delivery method was announced by Queensland University biomedical engineer Mark Kendall at TEDGlobal 2013 in Edinburgh, and could pave the way for safer, more efficient and more widespread vaccinations.
Drug delivery via needles has changed little in the past 150 years, and still carries risks associated with invasive procedures — for example, doctors being accidentally stuck with a used needle. Needles obviously have to be sterilised, and vaccines kept at cool temperatures to maintain their stability. The nanopatch, however, would mean vaccines could be distributed in rural regions with soaring temperatures without those same fears, and without risk of contamination. According to Kendall, it will remain viable even if kept at temperatures of 23 degrees celsius for a year.
Within the nanopatch are thousands of projections of dry-coated vaccines, Kendall explained at the conference, which means the drug goes straight to the cells under the skin, not via the muscle as with traditional vaccines.
Trials have already shown that administering flu vaccines to animals using the technique have proven to be more effective even at lower than traditional doses. In one trial, less than one hundredth of the normal dose was necessary to immunise the animal. Reaching the necessary cells faster means the overall drug quantity does not need to be as high, reducing production costs significantly.
“The projections on the nanopatch work with the skin’s immune system,” the BBC reports Kendall as saying. “We target these cells that reside just a hair’s breadth from the surface of the skin. It seems that we may have been missing the immune sweet spot which may be in the skin rather than the muscle which is where traditional needles go. A vaccine that had cost $10 (£6.40) can be brought down to just 10 cents, which is very important in the developing world.”
In 2010, a similar technique developed at Emory University and Georgia Institute of Technology showed that patches covered in “microneedles” would dissolve on contact after penetrating the skin. These too proved to be more effective than traditional methods when administered to mice, suggesting we’ve been stabbing ourselves in the muscle for years for no particular reason, missing what Kendall calls the “immune sweet spot”.
Although we’re at the early days of human trials, the nanopatch could herald a day of safe, cheap and efficient, self-administered drug delivery.
Source : Liat Clark, Wired.co.uk | June 13, 2013