Head-to-head comparison of three mRNA vaccines reveals differences in their stability in human blood

A recent study conducted by Australian researchers at the Olivia Newton-John Cancer Research Institute and the Peter Doherty Institute for Infection and Immunity has compared three mRNA-LNP vaccine platforms in human blood samples. The research, published in ACS Nano, could significantly improve cancer treatment and vaccine design.

The study analyzed 327 blood samples from 73 participants who received Moderna, Pfizer or an investigational COVID-19 mRNA vaccine. The researchers examined the presence and integrity of mRNA cargo after delivery, the stability of lipid-based packaging, and the degradation of mRNA cargo in the blood.

Dr. Yi (David) Ju, senior author of the paper, noted that different mRNA vaccines behave differently in the bloodstream. They found variations in the decline of mRNA and lipid components, as well as the duration of intact mRNA sections. Additionally, much of the circulating mRNA in the Moderna and Pfizer groups was fragmented.

Further analysis of six Moderna recipients revealed that mRNA was less intact near one end of the mRNA molecule, a pattern consistent with the original vaccine formulation. The findings provide valuable insights into how to enhance vaccine stability, potentially leading to more efficient vaccines and reduced side effects for patients.

Professor Stephen Kent, first author of the study, emphasized that these findings offer a method to compare the mRNA cargo and lipid delivery components of various vaccines in human trials. This knowledge will aid in designing and evaluating future improved mRNA vaccines and therapeutics, including those targeted for cancer treatment. The study establishes a framework for comparing mRNA-LNP platforms in humans, which will guide the development of more effective mRNA-based medicines.