Forget large, intimidating needles. Researchers in Georgia are developing a vaccine that feels more like a Band-Aid when administered. The vaccine patch contains hundreds of tiny microneedles that dissolve straight into the skin.
I spoke this week with Sean Sullivan, lead author of the study in Nature: Medicine and a former doctoral student at Georgia Institute of Technology, about the possibility of painless vaccines.
How can a vaccine be made painless?
It really ends up being the delivery device. Currently you use a needle because it's effective. It's been shown to deliver a countless number of drugs. It's effective and most medically-trained personnel can deliver a shot. You usually go into the muscle because it's easy. That's the current use.
What we're looking at is how to make it more patient compliant, how to make people want to get their injector. These microneedles, the reason they don't hurt is that they don't go deep enough to where the nerves are. A typical needle is multiple millimeters long. These microneedles are less than a millimeter in length. They're so short that they go very shallow into the skin and they don't reach where the nerves are. That's why these don't hurt and the current needle does.
How did you develop microneedles that could deliver vaccines?
The idea of microneedles has been around a number of years. In the late '90s they really started looking into this, the idea of if you use a small needle it won't hurt. How do we make this effective? They used a number of different technologies. They used glass, metal and silicone for microneedles. When I joined the project when I entered graduate school back in 2002, I was tasked to come up with a way of making a polymer microneedle. The main benefit of a polymer microneedle is it can dissolve in the skin and you have no needles left afterwards. Six years of a Ph.D. later, it works.
If the microneedles don't go as deep as traditional needles, are they as effective?
This is actually where it gets really gets interesting. For vaccinations specifically, the skin is actually one of the places that people would like to deliver. The skin has a number of immune cells in it. If you can get a vaccine right there, you can actually get a stronger immune response with the same dose. Because of that you can give a lower dose and get the equal immune response. In theory, if you're able to deliver to the skin and not the muscle for, let's say, the flu vaccine, you can give a lower dose and get the same response. It's great. How do you get things in the skin? That's where you get microneedles. You're delivering to those immune cells. Microneedles and vaccines are really a match made in heaven. It's a delivery device that's perfect for vaccinations. Not only does it not hurt, but you could theoretically get a lower dose with it.
How far along is the technology and what's the next step?
I'm no longer at Georgia Tech. This technology is all at Georgia Tech and Emory. My adviser is continuing with it. All the vaccinations we did were in animals. The next step would be to move to human trials and I believe they're working on that right now. The technology is ready to go there, but they would have to be tested in clinical trials first to make sure they're safe and effective in humans.
In addition to being less painful and more effective, what are the other benefits of microneedles?
You don't have a needle to get rid of afterwards, so there's not even a possibility of a re-stick to yourself or someone else. Because that's the case, there's a possibility in the future that this could be used at home. You could pick this up at the pharmacy and apply it to yourself and throw the backing away. You could self administer. That's how easy it is. It's as easy as putting on a Band-Aid. The self administration idea could have a huge impact.
We talked about mass immunization efforts. With these, you could pick them up or it might be very quick. You don't need highly-trained medical personnel to apply these to you. Another aspect we talked about is overseas in places where medically-trained personnel aren't available as much, sharp disposal isn't available, third-world countries. This would be a perfect vaccination device system for those locations.
Image, top: Microneedles on finger / Jeong-Woo Lee, Georgia Tech
Image, bottom: Sean Sullivan
This post was originally published on Smartplanet.com