(Reuters) – AstraZeneca said on Thursday its COVID-19 vaccine was 76% effective in a new analysis of its U.S. trial – 3 percentage points lower than the level in an earlier report this week criticised for using outdated data.
The following are details of the British vaccine:
TYPE OF VACCINE
** The vaccine is a recombinant viral vector vaccine, using a weakened version of a chimpanzee common cold virus to deliver instructions for making coronavirus spike proteins in cells, which will generate an immune response and prevent infection.
** Branded COVID-19 Vaccine AstraZeneca and scientifically called AZD1222 or ChAdOx1 nCoV-19. Serum Institute of India is making the vaccine, branded Covishield, based on the same technology to largely supply to low-to-middle income countries through the COVAX vaccine sharing programme.
DOSAGE AND STORAGE
** The two-doses regimen can be given four and 12 weeks apart in the UK, although tests have shown longer gaps could lead to higher immunity. Regimens vary between countries, as some also seek to delay second doses in order to give more people initial protection.
** The vaccine should be effective against the new coronavirus variants, AstraZeneca has said
** It can be stored, transported and handled at normal refrigerated conditions for at least six months, making it logistically easier to transport than some other vaccines.
** The vaccine has been sold for between $3 to $15 in government and private channels in various regions, including Europe, India, and Latin America.
** AstraZeneca has said it would not profit from the vaccine during the pandemic. The company said it will look to profit from wealthier countries at an “appropriate time”.
UK, BRAZIL AND SOUTH AFRICA
** A late-stage trial of about 11,000 people showed efficacy on average of about 70.4%, based on different dose regimens four weeks apart.
** A longer gap, rather than a one-month interval, could lift the success rate of the AstraZeneca/Oxford vaccine to 80%, a UK health official said.
** The latest data based on 190 infections among more than 32,400 participants in the U.S., Chile and Peru, showed the vaccine was 76% effective in preventing symptomatic coronavirus infections.
** Interim data published on Monday was based on 141 infections through Feb. 17, and pegged vaccine efficacy at 79%.
** The U.S. National Institute for Allergy and Infectious Diseases (NIAID) then said the board charged with ensuring the trial’s accuracy and safety had expressed concern the company may not have provided the most up-to-date data, potentially giving an incomplete view of effectiveness.
** The shot remains 100% effective against severe or critical COVID-19 illness and hospitalisation and posed no increased risk of blood clots, the company said.
APPROVALS AND PRODUCTION
** The vaccine has been given the go-ahead with conditions or for emergency use in more than 70 countries. The company expects to apply for U.S. emergency use authorisation in April.
** Canada updated its label to provide information on rare blood clots associated with a low platelet count following a shot.
** South Africa has delayed rolling it out because of a lack of data on its efficacy against the highly contagious variant identified there.
** AstraZeneca has said it plans to produce about 3 billion doses this year, and aims to produce more than 200 million doses per month by April.
** It has manufacturing deals with at least 20 companies worldwide for different stages of the supply chain, from making the antigen to final fill and finish steps.
(Sources: Reuters reporting, media releases, clinical trial registers, regulatory bodies, medical journals, World Health Organization)
Reporting by Pushkala Aripaka, Tanishaa Nadkar and Vishwadha Chander in Bengaluru; editing by Josephine Mason and Jason Neely