Advisor: Mark R. Prausnitz, PhD, ChBE, Georgia Tech
Julie A. Champion, PhD, (ChBE, Georgia Tech)
Jonathan S. Colton, PhD, (ME, Georgia Tech)
Krishnendu Roy, PhD, (BME, Georgia Tech)
William C. Weldon, PhD, (Centers for Disease Control and Prevention)
Formulation and clinical translation of microneedles for vaccination in developing countries
Most vaccines are currently administered by healthcare personnel using a needle and syringe. This delivery method poses significant hurdles in vaccine delivery, especially in developing countries. We propose dissolving microneedle patches to be a suitable alternative to needle and syringe vaccination in developing countries. Dissolving microneedle patches contain micron sized needles made out of water-soluble biodegradable polymers that dissolve in the skin to deliver the vaccine. They offer the simplicity of patch application and the possibility to mitigate the logistical and safety challenges associated with conventional hypodermic needles.
The overall goal of this thesis was to develop dissolving microneedle patches to further clinical translation of this technology in the context of vaccinations in developing countries. We studied two specific scenarios, development of microneedle patches for rabies vaccination of dogs and assessment of dissolving microneedle patches in human subjects. Human rabies is eliminated in most developed countries by employing control measures of vaccinations in animals. However, dogs account for nearly all human rabies infections in developing countries and vaccinations are difficult to employ in animals due to the need of a needle and syringe and the cost of administration. While microneedle patches are in pre-clinical development for different vaccines, limited information is available about their use in human subjects, which will be important for clinical translation.
The central hypothesis was that rabies vaccine can be stabilized in a dissolving microneedle patch and be at least as immunogenic as conventional needle and syringe while enabling simple administration and that dissolving microneedle patches could be easily administered without the need of an applicator, be well tolerated in the skin and preferred over needle and syringe administration. This was assessed by engineering patches for veterinary rabies vaccination and evaluating immune response in dogs and determining tolerability, usability and acceptability of placebo microneedle patches in human subjects. Altogether, the results from this thesis should further clinical translation of microneedles for vaccination in developing countries.