Georgia Institute of Technology, the nonprofit PATH, and Emory University recently received a $10 million grant from the National Institutes of Health for development and Phase I clinical trial investigation of a microneedle delivery technique for influenza vaccine. This method involves placing a patch containing vaccine-coated microneedles on the skin, where the needles and vaccine slowly dissolve. A backing that is left behind can be safely and easily discarded.
Apart from their ease of administration, the patches offer a potential benefit in that they might generate immunity better than traditional influenza vaccine. Influenza vaccination usually involves injecting the vaccine into muscle tissue. But the microneedles deliver vaccine into the skin, where larger numbers of antigen-presenting cells are present. Antigen-presenting cells (APCs) are a key factor in generating immunity: they recognize antigens, ingest them and break them apart, and present the pieces to other immune cells that then neutralize and remember the antigens. Activating larger numbers of APCs could lead to a more robust immune response.
Ioanna Skountzou, co-principal investigator for the project and an assistant professor in Emory University School of Medicine’s Department of Microbiology and Immunology, describes this important potential benefit of the microneedle vaccine delivery technique: “We have seen evidence that the vaccine works even better when administered to the skin because of the plethora of antigen presenting cells which reside there…..This study will allow us to determine how we can optimize the vaccine to take advantage of those cells that are important in generating the body’s immune response.”
Researchers have studied the microneedle system in animals and have shown it to be more effective in evoking immunity than an injected vaccine.
Investigators at Geogia Tech will conduct additional design and development of the microneedle patch. PATH will analyze the medical and regulatory implications of a self-administered vaccine. Vaccine development, immunological studies, and the Phase I trial will occur at Emory University. Promising results from the Phase I trial would likely result in the Phase II and Phase III clinical trials that would be required to obtain FDA approval.
It’s possible that the microneedle delivery technique could be applied to a wider range of vaccines than just influenza. Skountzou clearly hopes so: as she says, “Combined with the convenience of self-administration, painless application and absence of sharps waste, this novel immunization route could make the microneedle patch a powerful new weapon against infectious diseases.”
Microneedle Flu Immunization: NIH Awards $10 Million to Advance Technology for Painless, Self-Administration of Vaccine http://shared.web.emory.edu/emory/news/releases/2010/11/nih-awards-10-million-to-advance-microneedle-flu-immunization-technology.html Accessed 11/17/2010
Sullivan SP, Koutsonanos DG, del Pilar Martin M, Lee JW, Zarnitsyn V, Choi SO, Murthy N, Compans RW, Skountzou I, Prausnitz MR, Dissolving polymer microneedle patches for influenza vaccination. Nature Medicine. 2010;16:915–920. http://www.nature.com/nm/journal/v16/n8/abs/nm.2182.html. Accessed 11/17/2010.