The vaccine was developed at the University of Oxford Jenner Institute.  It uses a replication-deficient chimpanzee adenovirus to deliver a SARS-CoV-2 protein to induce a protective immune response. ChAdOx1 has been used to develop investigational vaccines against several pathogens, including a closely related coronavirus that causes Middle East respiratory syndrome (MERS). The scientists quickly adapted the platform to SARS-CoV-2 when the first cases of COVID-19 emerged. They showed that the vaccine rapidly induced immune responses against SARS-CoV-2 in mice and rhesus macaques. They then conducted vaccine efficacy testing on the macaques at NIAID’s Rocky Mountain Laboratories (RML) in Hamilton, Montana. Six animals that received the investigational vaccine 28 days before being infected with SARS-CoV-2 were compared with three control animals that did not receive the vaccine. The vaccinated animals showed no signs of virus replication in the lungs, significantly lower levels of respiratory disease and no lung damage compared to control animals. Oxford University has entered into a partnership with UK-based global biopharmaceutical company AstraZeneca for the further development, large-scale manufacture and potential distribution of the vaccine. Reference: “ChAdOx1 nCoV-19 vaccination prevents SARS-CoV-2 pneumonia in rhesus macaques” by Neeltje van Doremalen, Teresa Lambe, Alexandra Spencer, Sandra Belij-Rammerstorfer, Jyothi N. Purushotham, Julia R. Port, Victoria Avanzato, Trenton Bushmaker, Amy Flaxman, Marta Ulaszewska, Friederike Feldmann, Elizabeth R. Allen, Hannah Sharpe, Jonathan Schulz, Myndi Holbrook, Atsushi Okumura, Kimberly Meade-White, Lizzette Pérez-Pérez, Cameron Bissett, Ciaran Gilbride, Brandi N. Williamson, Rebecca Rosenke, Dan Long, Alka Ishwarbhai, Reshma Kailath, Louisa Rose, Susan Morris, Claire Powers, Jamie Lovaglio, Patrick W. Hanley, Dana Scott, Greg Saturday, Emmie de Wit, Sarah C. Gilbert and Vincent J. Munster, 13 May 2020, bioRxiv.DOI: 10.1101/2020.05.13.093195 Vincent Munster, Ph.D. is the chief of the Virus Ecology Unit in NIAID’s Laboratory of Virology.