ChAdOx1 nCoV-19

ChAdOx1 nCoV-19

ChAdOx1 nCoV-19 is a vaccine candidate which consists of the replication-deficient simian adenovirus vector ChAdOx1, containing the genetic sequence of the SARS-CoV-2 Spike protein.

University of Oxford researchers from the Jenner Institute have begun testing a COVID-19 vaccine in human volunteers in Oxford. Around 1,110 people will take part in the trial, half receiving the vaccine and the other half (the control group) receiving a widely available meningitis vaccine. The Phase 1 trial started on April 2020.

The team in Oxford is led by Prof. Sarah Gilbert, Prof. Andrew Pollard, Prof. Teresa Lambe, Dr Sandy Douglas and Prof. Adrian Hill. They started work designing a vaccine on Saturday 10th January 2020. The ChAdOx1 nCoV-19 vaccine candidate is made from a virus (ChAdOx1), which is a weakened version of a common cold virus (adenovirus) that causes infections in chimpanzees, that has been genetically changed so that it is impossible for it to grow in humans.

The team working on this vaccine have previously worked on the Ebola Vaccine in 2014 and have also worked on a vaccine for another coronavirus disease - Middle Eastern Respiratory Syndrome (MERS).

Animal Trial

A single dose of the ChAdOx1 nCoV-19 vaccine has protected six rhesus macaques from pneumonia caused by SARS-CoV-2, according to National Institutes of Health scientists and University of Oxford collaborators. The researchers posted their data to the preprint server bioRxiv. The findings are not yet peer-reviewed but are being shared to assist the public health response to SARS-CoV-19.

The scientists quickly adapted the platform to SARS-CoV-2 when the first cases of COVID-19 emerged. They showed that the vaccine 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.


ChAdOx1 nCoV-19 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). ChAdOx1 was chosen as the most suitable vaccine technology for a SARS-CoV-2 vaccine as it can generate a strong immune response from one dose and it is not a replicating virus, and cannot cause an ongoing infection in the vaccinated individual. This also makes it safer to give to children, the elderly, and anyone with a pre-existing condition such as diabetes.

Coronaviruses have club-shaped spikes on their outer coats. The Oxford vaccine contains the genetic sequence of this surface spike protein inside the ChAdOx1 construct. After vaccination, the surface spike protein of the coronavirus is produced, which primes the immune system to attack the coronavirus if it later infects the body.


May 15, 2020

Investigational ChAdOx1 nCoV-19 vaccine protects monkeys against COVID-19 pneumonia

Study provided data for clinical testing to commence.

April 30, 2020

University of Oxford Partners with the biopharmaceutical company AstraZeneca to Accelerate Globalization of COVID-19 Vaccine in Clinical Trials.

April 23, 2020

Oxford COVID-19 vaccine begins human trial stage | University of Oxford

March 27, 2020

Oxford COVID-19 vaccine programme opens for clinical trial recruitment | University of Oxford



Dr. Sandy Douglas

Vaccine Designer

Prof. Adrian Hill

Vaccine Designer

Prof. Andrew Pollard

Vaccine Designer

Prof. Sarah Gilbert

Vaccine Designer

Prof. Teresa Lambe

Vaccine Designer

Further reading


ChAdOx1 nCoV-19 vaccination prevents SARS-CoV-2 pneumonia in rhesus macaques


May 13, 2020

Documentaries, videos and podcasts


Chadox1: Oxford University Researchers Promise COVID Vaccine By September

April 18, 2020




May 24, 2020
Sky News
Professior Adrian Hill describes the efforts to create a vaccine as a "race against the virus disappearing, and against time".
Press Trust of India
May 22, 2020
The first phase of the trial began last month with 1,000 healthy adults aged 55 and under as volunteers.
BS Web Team
May 20, 2020
The vaccines failure to prevent the virus from attacking the rhesus macaque is a setback and kills the hope of treating humans


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