For parents who vaccinate, watching their children get stuck with a needle is a heart-wrenching experience. New biomedical technology may soon make multiple injections a thing of the past.
Researchers at MIT have developed technology that could allow childhood vaccines to be combined and administered in one single injection. The technology, as described in the Journal Science, would allow for a drastic decrease in the number of shots a child would require.
Utilizing 3-D printing, the scientists have created a “microparticle” made from FDA-approved polymers. These miniature capsules resemble tiny coffee cups that can be filled with a vaccine and then sealed with a lid. The microparticle is then injected into the patient. The polymers are designed to break down at predetermined times, thus spilling the contents out of the “cup” and into the body.
“We are very excited about this work because, for the first time, we can create a library of tiny, encased vaccine particles, each programmed to release at a precise, predictable time, so that people could potentially receive a single injection that, in effect, would have multiple boosters already built into it. This could have a significant impact on patients everywhere, especially in the developing world where patient compliance is particularly poor,” says MIT Professor Robert Langer.
The project was funded by the Bill & Melinda Gates Foundation, who wanted to find a single injection mechanism to deliver several vaccine doses over a period of time. The researchers say that the new technology could prove helpful in developing countries where patient compliance is often poor.
The concept has not yet been tested on humans. However, the particles were successfully tested on mice. The scientists found that the “cups” released their contents as scheduled on day 9, 20, and 41 after injection. None of the materials leaked before they were expected to be released.
There is still work that needs to be done before testing on humans can begin.
For vaccines to be effective, they need to be stored at a particular temperature. Typically, this involves refrigeration. Scientists will need to figure out how to keep the doses stable in a warm body.
Additionally, the microparticles are still too large to inject into the muscle as we normally administer vaccines. The scientists are working on a method of shrinking the microparticles.
Some parents and scientists are already voicing concerns about the technology. David Goldblatt, professor of vaccinology and immunology at University College of London noted that the one-time injection removed the chance to modify vaccines between doses and that there was no way to adjust the timing of the vaccine once it was injected.
Vaccines do not come without the potential for side effects. The Vaccine Adverse Event Reporting System (VAERS) is a national vaccine safety surveillance program run collaboratively by the CDC and FDA. According to the VAERS, approximately 30,000 adverse immunization events are reported each year.
Some parents fear that a single injection will not allow them to differentiate the culprit if there is an adverse reaction. Other parents worry about the possibility of malfunction, such as the effects if the “cups” open prematurely or all at once.
Certainly, there is a long way to go regarding FDA approval, and the outcome is sure to evoke a controversial debate.