Once front-runners in a global race to develop a vaccine, the AstraZeneca and University of Oxford partnership has been overtaken by Pfizer and German partner BioNTech, whose vaccine is already being used in Britain and the United States.

The following are details of the Oxford-AstraZeneca vaccine effort:

TYPE OF VACCINE

*Called AZD1222 or ChAdOx1 nCoV-19, the vaccine is a recombinant viral vector vaccine, meaning a virus is used as a means of delivering the vaccine.

*It will be branded COVISHIELD in India and is being manufactured there by partner Serum Institute of India.

*It uses a weakened version of a chimpanzee common cold virus that encodes instructions for making proteins from the novel coronavirus to generate an immune response and prevent infection.

DOSAGE, PROTECTION DURATION AND STORAGE

*India has authorised a two full-dose regime.

*UK authorisation recommends two-dose regime given between four and 12 weeks apart.

*Two regimens are being tested: one in which recipients get two full doses, and another with half a dose followed by a full dose.

*The half-dose first regimen was found to be 90% effective in a subset of trial subjects. The success rate was 62% with the originally planned two full doses, based on interim data.

*In December, Oxford said the vaccine has a better immune response when a two full-dose regime is used, citing data from early trials.

*Immune response could last at least a year.

*The vaccine should be effective against the new coronavirus variant, and studies are under way to fully probe the impact of the mutation.

*The vaccine can be stored, transported and handled at normal refrigerated conditions for at least six months, making it logistically easier to transport than Pfizer's vaccine.

*AstraZeneca aims to supply millions of doses in the first quarter to Britain and is working with the UK government for first vaccinations to begin early in the new year.

EXPECTED DOSAGE PRICE

*Serum Institute of India has said it would price the vaccine at 250 rupees (about $3) per dose for India's government and many other countries and at 1,000 rupees for the private market.

*Pricing in Britain is unknown so far.

*Italy's health ministry said in June the vaccine would cost about 2.5 euros ($2.80) per dose in Europe.

*AstraZeneca has said it will be able to manufacture the vaccine at a few dollars per dose.

*Pricing in Latin America is not expected to exceed $4 per dose.

*Sources told Reuters it could cost $4 to $5 per dose in Bangladesh.

*Costs in other regions have not yet been disclosed.

*AstraZeneca has said it would not profit from the vaccine during the pandemic, but a report from the Financial Times in October showed the company can declare when it considers the pandemic to have ended in its deals for the vaccine.

*AstraZeneca will look to profit from wealthier countries at the "appropriate time".

TESTING AND DATA

*Trials combining the vaccine with Russia's Sputnik V will start by the end of the year, and Russia wants to jointly produce the new vaccine if it is proven to be effective.

*Vastly divergent performance with different dose regimens has called for more clarity on the vaccine's efficacy which averaged 70.4%, well below vaccines from Pfizer and Moderna, but above the 50% threshold set by many regulators.

*Serum Institute of India will continue to test a two full dose regimen of the vaccine.

*AstraZeneca had to pause global trials on Sept. 6 after an unexplained illness in a participant.

*Trial of the vaccine in the United States resumed in October after other countries had ended their pause.

*AZD1222 produces an immune response in both old and young adults, and also led to lower adverse responses among the elderly, AstraZeneca said in October.

*The vaccine also accurately follows genetic instructions programmed into it by its developers, according to an analysis by independent scientists.

*Brazil said in October that a trial volunteer had died.

*A source told Reuters the Brazilian trial would have been suspended if the volunteer who died had received the COVID-19 vaccine, although the death was reported to be a suicide.

*In July, data from early-stage trials published in The Lancet showed the vaccine was safe and produced an immune response.

DATA AND REGULATORY TIMELINE

*The lead developer had said in July the vaccine could be rolled out by year-end, but the delivery and testing timeline has since been pushed back.

*Data read-out submitted to regulators across the world to seek approval.

*Experts have predicted a safe and effective vaccine could take 12-18 months to develop, even at the record speeds.

TARGET DOSES/GLOBAL CAPACITY OF SUPPLY

*More than 3 billion doses are planned.

*The company will have as many as 200 million doses by the end of 2020, and 700 million doses could be ready globally as soon as the end of the first quarter of 2021.

*AstraZeneca is keeping the vaccine frozen in large containers and will only add a final ingredient, put it into vials and refrigerate it when the vaccine gets closer to approvals.

TIE-UPS

*Even before studies showed any signs of efficacy, AstraZeneca had signed several supply and manufacturing deals around the world.

*It also joined forces with IQVIA to speed up testing.

*AstraZeneca has been granted protection from future liability claims related to the vaccine by most of the countries with which it has struck supply agreements, a senior executive told Reuters in July.

(Reporting by Pushkala Aripaka, Tanishaa Nadkar and Aakash Jagadeesh Babu in Bengaluru; Editing by William Maclean, Patrick Graham and Carmel Crimmins)