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AstraZeneca seeks WHO emergency approval for its up to 90% effective vaccine

AstraZeneca said Monday, 23 November, that trials showed its coronavirus vaccine AZD1222 was up to 90% effective and that it would immediately apply for early approval of the vaccine where possible, as well as seek an emergency use listing from the World Health Organization, writes MedicalBrief.

No hospitalisations or severe cases of COVID-19 were reported in those receiving the vaccine.

Pfizer and Moderna last week reported preliminary results from late-stage trials showing their vaccines were almost 95% effective. Unlike the Pfizer and Moderna vaccines, the Oxford-AstraZeneca candidate doesn’t have to be stored at ultra-cold temperatures, making it easier to distribute,

The results are based on interim analysis of trials involving 23,000 people in the UK and Brazil of a vaccine developed by Oxford University. Late-stage trials are also underway in the US, South Africa, Japan, Russia, Kenya and Latin America, with further trials planned in Europe and Asia.

“These findings show that we have an effective vaccine that will save many lives,” Oxford University Professor Andrew Pollard, chief investigator, said in a statement. “Excitingly, we’ve found that one of our dosing regimens may be around 90% effective.”

The AstraZeneca trial looked at two different dosing regimens. A half-dose of the vaccine followed by a full dose at least one month later was 90% effective. Another approach, giving patients two full doses one month apart, was 62% effective. The combined results showed an average efficacy rate of 70%.

Peter Openshaw, professor of experimental medicine at Imperial College London, said in an AP News report that the finding that a smaller initial dose is more effective than a larger one is good news because it may reduce costs and mean more people can be vaccinated.

“The report that an initial half-dose is better than a full dose seems counterintuitive for those of us thinking of vaccines as normal drugs: With drugs, we expect that higher doses have bigger effects, and more side-effects,” he said. “But the immune system does not work like that.”

AstraZeneca has been ramping up manufacturing capacity, so it can supply hundreds of millions of doses of the vaccine starting in January, Chief Executive Pascal Soriot said earlier this month.

AstraZeneca's full statement:

AZD1222 vaccine met primary efficacy endpoint in preventing COVID-19

Two different dosing regimens demonstrated efficacy with one showing a better profile. No hospitalisations or severe cases of COVID-19 in participants treated with AZD1222.

Positive high-level results from an interim analysis of clinical trials of AZD1222 in the UK and Brazil showed the vaccine was highly effective in preventing COVID-19, the primary endpoint, and no hospitalisations or severe cases of the disease were reported in participants receiving the vaccine. There were a total of 131 COVID-19 cases in the interim analysis.

One dosing regimen (n=2,741) showed vaccine efficacy of 90% when AZD1222 was given as a half dose, followed by a full dose at least one month apart, and another dosing regimen (n=8,895) showed 62% efficacy when given as two full doses at least one month apart. The combined analysis from both dosing regimens (n=11,636) resulted in an average efficacy of 70%. All results were statistically significant (p<=0.0001). More data will continue to accumulate and additional analysis will be conducted, refining the efficacy reading and establishing the duration of protection.

An independent Data Safety Monitoring 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. AZD1222 was well tolerated across both dosing regimens.

AstraZeneca will now immediately prepare regulatory submission of the data to authorities around the world that have a framework in place for conditional or early approval. The Company will seek an Emergency Use Listing from the World Health Organization for an accelerated pathway to vaccine availability in low-income countries. In parallel, the full analysis of the interim results is being submitted for publication in a peer-reviewed journal.

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% effective and if this dosing regime is used, more people could be vaccinated with planned vaccine supply. Today’s announcement is only possible thanks to the many volunteers in our trial, and the hard working and talented team of researchers based around the world.”

Pascal Soriot, Chief Executive Officer, 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.”

The pooled analysis included data from the COV002 Phase II/III trial in the UK and COV003 Phase III trial in Brazil. Over 23,000 participants are being assessed following two doses of either a half-dose/full-dose regimen or a regimen of two full doses of AZD1222 or a comparator, meningococcal conjugate vaccine called MenACWY or saline. The global trials are evaluating participants aged 18 years or over from diverse racial and geographic groups who are healthy or have stable underlying medical conditions.

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 enrol up to 60,000 participants globally.

The Company is making rapid progress in manufacturing with a capacity of up to 3 billion doses of the vaccine in 2021 on a rolling basis, pending regulatory approval. The vaccine can be stored, transported and handled at normal refrigerated conditions (2-8 degrees Celsius/ 36-46 degrees Fahrenheit) for at least six months and administered within existing healthcare settings.

AstraZeneca continues to engage with governments, multilateral organisations and collaborators around the world to ensure broad and equitable access to the vaccine at no profit for the duration of the pandemic.

COV002

COV002 is a single-blinded, multi-centre, randomised, controlled Phase II/III trial assessing the safety, efficacy and immunogenicity of AZD1222 in 12,390 participants in the UK. Trial participants to date are aged 18 years or over, who are healthy or have medically stable chronic diseases and are at increased risk for being exposed to the SARS-CoV-2 virus. Participants receive one or two intramuscular doses of a half dose (~2.5 x1010 viral particles) or full dose (~5×1010 viral particles) of AZD1222 or comparator, meningococcal vaccine MenACWY. Participants have blood samples drawn and clinical assessments for safety as well as immunogenicity at multiple timepoints up to one year post-vaccination. Suspected cases presenting with compatible symptoms were tested for virological confirmation by COVID-19 PCR. In addition, weekly swabbing are done for detection of infection and assessment of vaccine efficacy against infection.

COV003

COV003 is a single-blinded, multi-centre, randomised, controlled Phase III trial assessing the safety, efficacy, and immunogenicity of AZD1222 in 10,300 participants in Brazil. Trial participants to date are aged 18 years or over, who are healthy or have medically stable chronic diseases and are at increased risk for being exposed to the SARS-CoV-2 virus. Participants are randomised to receive two intramuscular doses of a full dose (~5×1010 viral particles) of AZD1222 or comparator, meningococcal vaccine MenACWY as first dose and a saline placebo as second dose. Participants have blood samples drawn and clinical assessments for safety as well as immunogenicity at multiple timepoints up to one year post-vaccination. Suspected cases presenting with compatible symptoms were tested for virological confirmation by COVID-19 PCR.

AZD1222

AZD1222 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.

 

[link url="httpUKKBN27P00S"]Full Reuters report[/link]

https://apnews.com/article/oxford-coronavirus-pandemic-c99d26eb2946f6fde45a1edc002ff028?utm_source=Sailthru&utm_medium=email&utm_campaign=AP%20Morning%20Wire&utm_term=Morning%20Wire%20Subscribers

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