An interim analysis of clinical trials in Brazil and the United Kingdom show a coronavirus vaccine co-developed by AstraZeneca and Oxford University is up to 90 percent effective.
It’s the third such announcement, with both the Pfizer and Moderna candidates showing up to 95 percent effectiveness in dealing with Covid-19.
The vaccine offers a major distribution advantage since it can be refrigerated at temperatures slightly above freezing.
By contrast, Pfizer and, to a lesser extent, Moderna candidates require freezers that can hold the vaccines at temperatures well below zero Fahrenheit
The storage advantage would allow the vaccine to be more quickly distributed in many parts of the world.
AstraZeneca will begin work to gain emergency approvals for the vaccine throughout the world. The U.S. government has invested $1 billion in the research effort with AZ agreeing to distribute 200 million doses here.
AstraZeneca has administrative and logistics operations in Delaware that at last report employed 1,500.
One dosing regimen showed vaccine effectiveness of 90 percent when the AstraZeneca-Oxford AZD1222 vaccine was given as a half dose, followed by a full dose at least one month apart.
Another dosing regimen showed 62 percent effectiveness when given as two full doses at least one month apart. Investors seemed to focus on the combined tests having a 70 percent efficacy figure, leading to a decline in AZ’s stock price.
An independent board determined that the analysis met its primary endpoint showing protection from Covid-19 occurring 14 days or more after receiving two doses of the vaccine. No serious safety events related to the vaccine have been confirmed.
AZ will seek an Emergency Use Listing from the World Health Organization for an accelerated pathway to vaccine availability in low-income countries.
Professor Andrew Pollard, chief investigator of the Oxford Vaccine Trial at Oxford, said: “These findings show that we have an effective vaccine that will save many lives. Excitingly, we’ve found that one of our dosing regimens may be around 90 percent effective, and if this dosing regime is used, more people could be vaccinated with planned vaccine supply.”
Pascal Soriot, AstraZeneca CEO, said: “Today marks an important milestone in our fight against the pandemic. This vaccine’s efficacy and safety confirm that it will be highly effective against Covid-19 and will have an immediate impact on this public health emergency. Furthermore, the vaccine’s simple supply chain and our no-profit pledge and commitment to broad, equitable, and timely access means it will be affordable and globally available, supplying hundreds of millions of doses on approval.”
Clinical trials are also being conducted in the US, Japan, Russia, South Africa, Kenya, and Latin America, with planned trials in other European and Asian countries. In total, the Company expects to enroll up to 60,000 participants globally. About 23,000 were enrolled in the UK and Brazil studies.
The trial was paused after one of the people taking the vaccine developed a rare condition. After determining that the condition was not linked to the vaccine, the trial resumed although U.S. regulators studied the matter longer than their counterparts elsewhere.
The company reported progress in manufacturing with a capacity of up to 3 billion doses of the vaccine in 2021, pending regulatory approval. The vaccine can be stored, transported, and handled at normal refrigerated conditions (36-46 degrees Fahrenheit) for at least six months and administered within existing healthcare settings.
Should the half-dose, full-dose protocol pan out, it could allow the AZ-Oxford vaccine to vaccinate more people at a lower cost.
AstraZeneca, based in Cambridge, UK, again pledged to work with governments, multilateral organizations, and collaborators worldwide to ensure broad and equitable access to the vaccine at no profit for the duration of the pandemic.
The AZD1222 vaccine was co-invented by the University of Oxford and its spin-out company, Vaccitech. It uses a “replication-deficient chimpanzee viral vector based on a weakened version of a common cold virus (adenovirus) that causes infections in chimpanzees and contains the genetic material of the SARS-CoV-2 virus spike protein. After vaccination, the surface spike protein is produced, priming the immune system to attack the SARS-CoV-2 virus if it later infects the body.”
