The first patients have been dosed with ChAdOx1 nCoV-19, an adenovirus vaccine vector (AAV) developed by the Jenner Institute at the University of Oxford. It becomes the fifth COVID-19 vaccine to enter the clinic.

Clinical trials of the vaccine, based on an adenovirus vaccine vector (AAV) and the SARS-CoV-2 spike protein, began today in healthy volunteers aged between 18 – 55 in Oxford, UK.

The vaccine was developed at Oxford’s Jenner Institute and was chosen as the most suitable vaccine technology for a SARS-CoV-2 (COVID-19) vaccine as it can generate a strong immune response from one dose and it is not a replicating virus, so it cannot cause an ongoing infection in the vaccinated individual.

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The program, which has received UK Government funding, represents a broad collaboration within Oxford and across the UK in the fight against COVID-19, said Catherine Green, a cell and molecular biology scientist who heads up the Clinical BioManufacturing Facility (CBF) for the Nuffield Department of Medicine – part of the team working the University of Oxford vaccine and the manufacturer of the trial batch.

“Vaccine development is a slow process but I can say quite honestly we have surpassed ourselves and are doing absolutely everything we can to get a vaccine made, trialed, proved to be safe, and to the public as quickly as possible,” she told UK-based radio station LBC Thursday.

“This is the fastest we’ve ever made a vaccine in Oxford and we’ve been doing this for about 20 years now using the same vector platform. We have had a lot of practice doing this for other diseases, but we’ve never managed to turn it around this quickly, but unprecedented times calls for unprecedented efforts”

The team previously used the tech to develop a vaccine against Middle East Respiratory Syndrome (MERS), which has shown promise in early clinical trials.

The initial trial, taking place in Oxford, London and Southampton (all UK), intends to prove the vaccine safe and is expected to take up to five months. The next challenge, Green said, is to scale up production for potentially millions of doses.

The CBF is working with the Vaccine Manufacturing and Innovation Centre (VMIC), Pall Biotech and Cobra Biologics on production, but recently added Dutch contract development and manufacturing organization (CDMO) Halix to the consortium. Halix’s newly constructed GMP facility has capacity of up to 1,000 L single-use bioreactor scale, and the transfer of an industrial scale drug substance process from Pall in the UK has already begun.

Another horse in the race

Adam Finn, professor of pediatrics at the University of Bristol and director of the Bristol Children’s Vaccine Centre at Bristol Medical School, is also involved in the project, and he told LBC that most vaccine candidates do not reach commercialization.

“Only the minority come through and are successful in the end. I think this vaccine has a good chance of success, but I think we need lots of horses in the race to be sure at least a few reach the finishing line.”

Green added that “there are many people developing vaccines around the world and we don’t need it to be ours that is successful – anyone of them will do at this stage.”

ChAdOx1 nCoV-19 is the fifth vaccine directly targeting COVID-19 to enter the clinic, according to RAPS’s COVID-19 vaccine tracker.

Moderna Therapeutics began Phase I trials of its mRNA candidate in March, while two weeks ago Inovio Pharmaceuticals began dosing patients with its DNA vaccine INO-4800.

Meanwhile, CanSino Biologics has developed a recombinant novel coronavirus vaccine that incorporates the adenovirus type 5 vector (Ad5) and is undergoing Phase I trials in Wuhan, China. And Sinovac’s formalin-inactivated and alum-adjuvanted candidate vaccine began trials last week.

Pfizer and BioNTech has a Phase 1/2 trial planned in Germany, though according to the tracker it has not yet begun.