mRNA vaccine technology has its intellectual origin in the work Katalin Karikó and Drew Weissman published in 2005: the discovery that chemically modifying messenger RNA with pseudouridine eliminated the inflammatory response that had made its therapeutic use unworkable. For decades mRNA was considered too unstable and immunogenic for clinical use. Karikó, a researcher of Hungarian origin, was demoted at the University of Pennsylvania in 1995 for refusing to abandon this line of research. When the COVID-19 pandemic began in January 2020, the mRNA platform was the only technology capable of producing a vaccine within weeks: BNT162b2 (BioNTech/Pfizer) and mRNA-1273 (Moderna) received emergency authorization in December 2020. BCG took 13 years to go from laboratory to patient; mRNA vaccines took 11 months. In 2023, Karikó and Weissman received the Nobel Prize.