Despite the fact that vaccination is one of the world’s most effective ways to save and protect lives, significant hurdles remain. In particular, measles is among the leading causes of vaccine-preventable death among children worldwide, and congenital rubella syndrome is a major cause of birth defects.
While an effective measles and rubella (MR) vaccine exists, the problem lies in delivery. To ensure proper storage and handling, the current MR vaccine must be kept refrigerated up to the point of injection. The vaccine must be delivered by trained medical personnel, and the syringes and needles must be disposed of properly.
Thanks to a CDC Foundation grant from UNICEF, a collaborative team from the Centers for Disease Control and Prevention (CDC), the Georgia Institute of Technology (Georgia Tech) and Micron Biomedical are on the verge of a breakthrough. By drying and stabilizing the MR vaccine, the researchers have been able to transfer the vaccine to a microneedle patch for delivery. The patch, a small flexible tab about the size of a thumbnail, consists of 100 tiny dissolving microneedles that deliver the vaccine through the skin.
“The patch is placed directly onto the skin and dissolves after a few minutes,” said Dr. Paul Rota, chief of CDC’s Viral Vaccine Preventable Diseases Branch, and a co-principal investigator on the study. “You can give someone a vaccine dose as easily as applying a bandage.”
This innovative approach addresses several of the critical challenges in the fight against measles and rubella. Chief among these, Rota said, is the fact that the dissolving microneedle patch may not require a cold chain to the point of delivery. Vastly more portable, the vaccine could potentially reach much deeper into areas that traditionally lack coverage and close a vaccine gap that has challenged global eradication efforts.
“I think this could be a game changer in allowing us to close the vaccination gap,” Rota said. “We need about 95 percent coverage to break transmission of measles and rubella. We’re hoping this might be able to significantly raise vaccine coverage, particularly in hard-to-reach areas.”
The ease with which the patch can be administered offers other benefits as well. In its injectable form, the MR vaccine must be prepared and administered by trained medical personnel. Injections also generate medical waste that can be difficult and costly to dispose of safely. The simplicity and design of the microneedle patch, Rota said, could eliminate both issues, while offering other advantages as well.
“With this patch you could train volunteers to go house to house to give kids the vaccination,” Rota said. “It also might help overcome some of the hesitancy associated with injectable vaccines, and be more accepted by children and parents.”
Though the MR microneedle patch still faces clinical trial in humans, experiments in non-human primates have shown tremendous promise. If it proves safe and effective, the MR microneedle vaccine would likely first be used as part of measles and rubella vaccination campaigns in the developing world where the disease threats are greatest. As the technology advances, Rota said, microneedle vaccinations offer almost unlimited potential.
“As someone who has been working with vaccinations for over 30 years now, I think this is the wave of the future,” Rota said.
A UNICEF grant to the CDC Foundation for a Measles-Rubella (MR) Project aims to simplify MR vaccination to increase vaccination coverage and lower vaccination costs. The collaboration between CDC, Georgia Tech and Micron is the first phase of an effort to develop a dissolving microneedle patch for MR vaccination that could potentially lead to higher vaccination coverage levels that are essential to eliminating measles and rubella.