Authors: Martha Powell, Future Science Group
In the first Phase I clinical trial, microneedle patches for flu vaccination have proved to be safe, well-tolerated, immunogenic and preferred by participants over traditional intramuscular injection. These patches could potentially improve current vaccine regimens and increase uptake of the flu vaccine.
Despite potentially severe consequences, in the USA only approximately 40% of adults get the flu vaccine each year. In this study, published recently in The Lancet, a team from Emory University and the Georgia Institute of Technology (both GA, USA) investigated the benefits of microneedles patches for administering vaccines in a healthy cohort.
First author Nadine Rouphael (Emory University) explained the potential of the patches: “Despite the recommendation of universal flu vaccination, influenza continues to be a major cause of illness leading to significant morbidity and mortality. Having the option of a flu vaccine that can be easily and painlessly self-administered could increase coverage and protection by this important vaccine.”
The trial enrolled 100 healthy individuals aged 18–49 and who had not received the influenza vaccine in the previous flu season. The participants were then randomized into four groups: vaccination with microneedle patch given by healthcare provider; vaccination with self-administered microneedle patch; vaccination via intramuscular injection given by healthcare provider; and placebo microneedle patch given by healthcare provider.
The researchers demonstrated that the patches induced robust immunity, with generation of antibodies being just as effective as standard injection and antibodies still present 6 months post-vaccine. In addition, the team discovered the microneedle patch was safe and well-tolerated, with no adverse events being reported. Skin reactions to patches were observed to be short-lived and relatively painless, with symptoms including faint redness and mild itching.
The group also reported that participants preferred vaccination with microneedle patches over injection with a hypodermic needle and syringe – over 70% of participants stated they would rather the microneedle delivery method for future vaccinations.
Finally, the team did not observe a difference between the doses of vaccine delivered when comparing administration by the participants themselves with healthcare providers. This demonstrates that self-administration was effective, and is a method that could reduce the cost of flu vaccination and potentially improve uptake.
Co-senior author, Mark Prausnitz (Georgia Institute of Technology), commented: “People have a lot of reasons for not getting flu vaccinations. One of the main goals of developing the microneedle patch technology was to make vaccines accessible to more people.
“Traditionally, if you get an influenza vaccine you need to visit a healthcare professional who will administer the vaccine using a hypodermic needle. The vaccine is stored in the refrigerator, and the used needle must be disposed of in a safe manner. With the microneedle patch, you could pick it up at the store and take it home, put it on your skin for a few minutes, peel it off and dispose of it safely, because the microneedles have dissolved away. The patches can also be stored outside the refrigerator, so you could even mail them to people.”
The researchers are working on pioneering this delivery method for other vaccinations, including measles and polio. Moving forwards, the team hope to test the microneedle patches on larger cohorts.
Prausnitz concluded: “It’s very gratifying and exciting to have these patches tested in a clinical trial, and with a result that turned out so well. We now need to follow this study with a Phase II clinical trial involving more people, and we hope that will happen soon.”
Sources: Rouphael NG, Paine M, Mosely R et al. The safety, immunogenicity, and acceptability of inactivated influenza vaccine delivered by microneedle patch (TIV-MNP 2015): a randomised, partly blinded, placebo-controlled, phase 1 trial. The Lancet. doi:10.1016/S0140-6736(17)30575-5 (2017) (Epub ahead of print); http://news.emory.edu/stories/2017/06/microneedles_flu_vaccine_patch/index.html