What do we know about vaccine mixing?

A major UK test exploring the potential of a mixed-and-match approach to Covid vaccination It has been extended to include Moderna and Novavax jabs.

Scientists behind the Oxford University-led Com-COV study hope that the combination of vaccines will provide “wider, longer-lasting immunity” against coronavirus and new variants. I am reporting. BBC.. The use of different brands of vaccines for the first and second doses provides additional flexibility in vaccine deployment.

In this study, Pfizer received an initial dose or AstraZeneca..

With more than 800 people already in the trial, Professor Matthew Snape of the Oxford Vaccine Group hopes to recruit more 1,050 volunteers who have been vaccinated once in the NHS in the last 8-12 weeks. is.

Volunteers will receive a second vaccination, which may be the same as the first vaccination, or a Moderna or Novavax vaccine.

Researchers are looking for side effects and immune system responses to new combinations of vaccines, rather than trying to find out if vaccines are effective in preventing disease.The study explains that it is designed to show that “mixing is not substantially worse than not mixing”. Sky news..

Most health professionals agree that vaccine mixing and matching should be safe. The trial tries to determine if there are possible combinations to avoid. Snape told the BBC that he hopes the trial “does not rule out possible combinations.”

“That’s the way we need to see it: are there any combinations we shouldn’t give because they don’t produce a good immune response?”

Danny Altmann, a professor of immunology at Imperial College who was not involved in the trial, said: CNBC Last week he could not see a debate about “why” the DPT vaccine is “unsafe or inadequate practice.”

“It will still provoke great immunity. No problem,” he said.

“There is no theoretical reason why it shouldn’t be feasible and safe, but we have to wait for these studies,” Andrew Friedman, a reader of Infectious Diseases at Cardiff University School of Medicine, told the press. It was.

Studies on the possibility of mixing different types of vaccines have been conducted by both European and UK health regulators with the Oxford-AstraZeneca vaccine. Blood clot, The risk for young adults is slightly higher.

United Kingdom Joint Committee on Immunization and Immunization (JCVI) emphasizes that the protection benefits that the AstraZeneca vaccine provides to Covid “much outweighs” the risk of side effects in the vast majority of people. However, the Commission advises that adults under the age of 30 without underlying health should be provided with an alternative vaccine “when available.”

French health regulators recommend that people under the age of 55 who receive the first dose of AstraZeneca use Pfizer or Moderna for the second dose. Germany also advises people under the age of 60 to choose a different vaccine for the second dose. ..

The Centers for Disease Control and Prevention in China says it is also considering mixing vaccines to increase efficacy. BBCThere is a suggestion that the efficacy of some vaccines officially approved in the country is as low as 50%. In contrast, the AstraZeneca vaccine is claimed to be 100% effective against severe or serious illness and 76% effective against symptomatological Covid.

The Russian Sputnik V vaccine involves using two slightly different doses to immunize.

Some results from the first phase of the Com-COV study are expected next month, but the trial has reportable findings by the summer.

Snape said, “We are probably not only in the UK, but also in Europe, which is considering limiting the use of vaccines in some age groups by mixing vaccines. There will be a lot of flexibility around the world. ” , A slightly more intermittent supply of vaccines. “
“Let’s hope that we can actually use this and get as many people as possible to get two doses of the vaccine.”