March 19, 2014
Patients prefer to administer their own vaccines using microneedle patches, according to a new study, which could help overcome the practical inconveniences and needle phobia that prevent many Americans from protecting themselves against the seasonal flu that claims thousands of lives each year.
The researchers assessed if 70 volunteers could effectively apply the patches — which were 3 cm in diameter with an array of 100 750 µm-microneedles that target vaccine delivery to the skin — with minimal training and gauged if the patches increased vaccination rates. The volunteers administered 3 placebo patches on their own using thumb pressure, had a patch applied by a study investigator, and received an investigator-administered intramuscular injection of 0.5 ml saline. Twenty-one additional participants used a snap-based device designed to provide tactile feedback when the force needed to optimize microneedle contact with the skin was applied.
According to the study, participants who used the snap-based device inserted a median value of 96% of microneedles on the first attempt, better than the 90% achieved by participants using thumb pressure only. The possibility of using patches also convinced 30% of participants to get vaccinated who otherwise wouldn’t have, noted the researchers. Additionally, 76% of the participants preferred microneedle-patch vaccination to conventional vaccination injections, and 64% preferred self-vaccination to vaccination by a healthcare worker.
The patches — either self-administered or investigator-administered — also caused significantly less discomfort than conventional injections: 1.5 and 15 pain scores, respectively, based on a 1 to 100 scale.
Offering self-administered patches could significantly reduce influenza hospitalizations and working days lost for patients if the study’s findings are extrapolated across the nation’s population, according to the researchers. They also suggested the cost of self-vaccination would match the approximate $5.50 it costs to stock, sell, and document individual vaccinations administered in a pharmacy.
“Every year more than 100 million flu vaccinations are given in the United States by pharmacists, nurses, doctors, and other healthcare professionals,” said study co-author Dr. Mark Prausnitz, professor of chemical and biomolecular engineering at the Georgia Institute of Technology.
“This study establishes the potential that patients could self-administer flu vaccines using a microneedle patch,” he added. “The participants were able to self-administer the patches reliably and preferred them by a factor of three-to-one to intramuscular injections.”
Dr. Prausnitz noted some patients receive flu shots administered by pharmacists. “If flu vaccine patches were available and could be self-administered, it’s likely that many more patients would obtain their flu vaccines in the pharmacy, but would no longer require pharmacists to administer the injection,” he added.
The article was published online in the journal Vaccine.
1. Norman JJ, Arya JM, McClain MA, Frew PM, Meltzer MI, Prausnitz MR. Microneedle patches: usability and acceptability for self-vaccination against influenza. Vaccine. 2014;32(16):1856-1862.