Effective vaccines without the use of a needle: Researchers have intensified their efforts to develop patches that deliver life-saving drugs to the skin. This breakthrough could change medicine.
This technique can save the tears of children at the doctors' office and could be used to help those with a fear of needles.
Skin patches, which don't require cold-chain requirements, could help with distribution efforts and may even increase vaccine efficacy.
A new study of mice in this area was published in Science Advances. It showed promising results.
The Australian-US team used one-square-centimeter-sized patches that were dotted by more than 5,000 microscopic spikes. "So tiny you can't even see them," David Muller (a virologist at University of Queensland) told AFP.
The tips are coated with an experimental vaccine and then the patch is applied with an applicator that looks like a hockey puck. Muller said, "It's almost like you have a good flick on your skin."
Researchers used a "subunit" vaccine to reproduce the spikes on the coronavirus' surface.
Mice were either injected via the patch for two minutes or using a syringe.
After two doses of the patch, the immune system produced high levels neutralizing antibodies in the lungs. This was vital for stopping COVID. The patches performed better than syringes.
Muller said that the researchers also discovered that mice who received only one dose vaccine containing an adjuvant, which is used to boost immune response, did not get sick.
It's easy to apply
What makes them more efficient?
Muller explained that vaccines are usually injected into the muscles. However, muscle tissue does not contain enough immune cells to react to the drug.
The tiny spikes can also cause skin death locally, which alerts your body to the problem and triggers an immune response.
The logistical benefits for scientists are unmistakable.
First, the vaccine can be dry-coated on a piece of skin for up to 30 days at 25° Celsius (77° Fahrenheit) or one week at 40C (10104F), as opposed to the Moderna and Pfizer vaccines which only last a few hours at room temperatures.
This is a huge advantage, especially for developing countries.
Muller added that second, it is "very simple to use." It doesn't require highly-trained medical professionals to administer it.
Burak Ozdoganlar is a Carnegie Mellon University professor of engineering in Pittsburgh. He has been involved with the technology since 2007.
He also sees another benefit: "A smaller amount of vaccine can activate an immune reaction similar to intramuscular injectables," he explained to AFP. This is an important aspect, as the developing world struggles with enough COVID vaccine.
Ozdoganlar is capable of producing 300-400 patches per day in his laboratory, but he has not been allowed to test them on mRNA vaccines.
"The future"
Vaxxas in Australia made the patch used for Friday's study. It is the furthest along. Human trials are planned for April.
Vaxess and Micron Biomedical, both from the United States, are also participating in this race.
This company was founded in Massachusetts in 2013. It works on a different kind of patch with microneedles which dissolve in the skin.
This method requires fewer spikes per spot, 121 of which are made from a biocompatible protein polymer.
"We're working on a seasonal COVID and flu combination product that will be mailed directly to patients' homes, for self-administration," CEO Michael Schrader told AFP.
Medigen is the manufacturer of the COVID vaccine that they use. It has been approved in Taiwan.
Vaxess recently opened a factory in Boston with funding from the US National Institutes for Health. The goal is to produce enough vaccine patches to give vaccinates to between 2,000 and 3,000 people in clinical trials that will be held next summer.
Production is the main problem right now, as no manufacturer has been able to produce enough patches in masse.
Schrader stated, "To launch a vaccine, you must produce hundreds of millions." "No one has this scale, and we don't have it."
He said that the pandemic had given an impetus to the industry's growth, and it is now attracted more investors.
Schrader stated, "This is the future. In my opinion, it's inevitable." "I believe you'll see that this (will) quite dramatically change the way we get vaccines all over the world in the next 10 years," Schrader said.
Agence France-Presse
