A National Institutes of Health-funded study led by a team at the Georgia Institute of Technology and Emory University has shown that an influenza vaccine can produce robust immune responses and be administered safely with an experimental patch of dissolving microneedles. The method is an alternative to needle-and-syringe immunization; with further development, it could eliminate the discomfort of an injection as well as the inconvenience and expense of visiting a flu clinic.
The study, published online on June 27, 2017, in The Lancet, was led by Nadine Rouphael, M.D., associate professor of medicine and Mark J. Mulligan, M.D., distinguished professor of medicine, Emory University School of Medicine, in collaboration with Mark R. Prausnitz, Ph.D., Regents Professor and J. Erskine Love Chair in Chemical and Biomolecular Engineering, Georgia Institute of Technology. A team led by Prausnitz designed the dime-sized patch of microneedles used in the study.
The vaccine patch consists of 100 solid, water-soluble needles just long enough to penetrate the skin. Adhesive helps the patch grip the skin during the administration of the vaccine.
The researchers enrolled 100 adult participants, dividing them into four random groups. The researchers used an inactivated influenza vaccine formulated for the 2014-15 flu season to inoculate participants other than those in the placebo group.
The results showed that antibody responses generated by the vaccine, as measured through analysis of blood samples, were similar in the groups vaccinated using patches and those receiving intramuscular injection, and these immune responses were still present after six months.
The prospective vaccine technology could offer economic and manufacturing advantages. The manufacturing cost for the patch is expected to be competitive with prefilled syringe costs. The patch, however, can dramatically reduce the cost of vaccination, since self-administration can eliminate the need to have health workers oversee the process. It can be easily packaged for transportation, requires no refrigeration, and is stable.
The team plans to conduct further clinical trials to pursue the technology’s ultimate availability to patients. They also are working to develop microneedle patches for use with other vaccines, including measles, rubella and polio.