The UK could be on the way to approving a fourth coronavirus vaccine after the new Novavax jab showed promising results in trials.
The new jab - which was found to be 89% effective in preventing Covid-19 - could be approved for use in the UK within weeks, further boosting the country's supply of vaccines.
If approved by the Medicines and Healthcare products Regulatory Agency, it will be manufactured in Stockton-on-Tees.
Meanwhile, the majority of the Oxford/AstraZeneca vaccine is set to be manufactured in the UK, despite initial doses coming from Germany, and the Pfizer/BioNTech vaccine is manufactured in Europe.
The UK has so far placed orders for 367 million doses of Covid vaccines, from seven different developers. Five final contracts have been signed, with AstraZeneca, Pfizer, Moderna, Valneva and Novavax - with the expected cost being £2.9 billion.
The government has made available more than £6 billion to develop and procure vaccines.
So what has the UK secured access to so far?
What are the different types of vaccines that have been ordered?
These are based on weakened versions of adenoviruses, which are a group of viruses that typically infect membranes of the eyes, respiratory tract, urinary tract, intestines and nervous system, and include the common cold.
Traditional vaccines are made up of small or inactivated doses of the whole disease-causing organism, or the proteins that it produces. They are injected into the body to provoke the immune system into responding. But mRNA vaccines trick the body into producing some of the viral proteins itself.
Inactivated whole virus vaccines
Inactivated vaccines contain whole bacteria or viruses which have been killed, or small parts of bacteria or viruses, such as proteins or sugars, which cannot cause disease.
Protein adjuvant vaccines
An adjuvant is a pharmacological or immunological agent that is added to some vaccines to enhance the immune response. The use of an adjuvant may reduce the amount of vaccine protein required per dose, which allows more vaccine doses to be produced.
What Covid vaccines has the UK approved so far?
Oxford and AstraZeneca (Adenovirus) - 100 million doses ordered
The jab is also being rolled out in the UK, after getting the green light from the Medicines and Healthcare products Regulatory Agency (MHRA) on December 30.
BioNTech / Pfizer (mRNA) - 40 million doses ordered
The vaccine is being rolled out across the UK, having been approved for use on December 2 last year.
Moderna (mRNA) - 17 million doses ordered
The jab from the US biotech firm has been approved for use in the UK, but doses will not be available until the spring.
What vaccines are still being developed and tested?
Novavax (Protein Adjuvant) - 60 million doses ordered
The UK is running a phase three trial for the vaccine. Results from trials show it offers 89% protection against Covid-19, but it still requires approval from the MHRA, which could take several weeks.
If approved, the vaccine will be manufactured in the UK with Fujifilm Diosynth Biotechnologies.
Janssen / Johnson & Johnson (Adenovirus) - 30 million doses ordered
Results of the ongoing Ensemble phase three clinical study are expected to be available later this month.
Valneva (Inactivated whole virus) - 60 million doses ordered
Valneva’s site in Livingston, West Lothian, will manufacture the vaccine. Phase 1 and 2 clinical trials are ongoing.
GlaxoSmithKline / Sanofi Pasteur (Protein Adjuvant) - 60 million doses ordered
Phase 1 and 2 clinical trials for the vaccine are ongoing. Interim results of early phases of the trial showed an immune response comparable to patients who recovered from Covid-19 in adults aged 18 to 49 years, but a low immune response in older adults.
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