Dried RNA vaccine particles retain activity after warm storage
MIT researchers identified a dried lipid-particle mixture that protected vaccine mRNA during warm storage. In animal experiments, stored formulations still elicited immune responses. The team used an algorithm to choose ingredients and compared the stored formulation with freshly prepared vaccine; the result does not establish protection, safety, or distribution performance in people.
Science··Evening
A dried mixture protects the RNA carrier
MIT researchers changed the ingredients surrounding lipid particles that carry vaccine mRNA, rather than altering the active genetic message. These particles protect a molecule that otherwise degrades readily, which is why many RNA vaccines need cold storage. The team screened nearly 50 approved excipients and used a light-producing RNA signal in cells to compare candidate mixtures. A small group of promising ingredients then entered an algorithm-guided search.[1]
Stored samples still trigger immune responses
The selected particles were dried under vacuum with mRNA encoding a coronavirus antigen. MIT reported storage for more than two months at 37 degrees Celsius and up to a year at room temperature. In mice, stored samples produced immune responses similar to a freshly prepared comparator. Antigen-specific responses were also observed in rodents and non-human primates. These measurements establish activity in the reported experiments, not protection against infection in people.[1], [2]
Delivery formats remain experimental
Researchers also put the formulation into dissolving microneedle patches and observed immune responses in animal tests. They selected stabilizing mixtures over six optimization rounds in about a month. Those results describe a way to develop dry particles for this experimental vaccine. They do not measure how a licensed product would fare across shipping conditions, how long human immunity would last or whether the formulation works with every RNA message.[1]
