Booster study: English researchers test vaccination effect with almost 3,000 participants. But the data have a crucial catch.
In Germany, the fight against Corona is currently all about initial vaccinations and boosters. Next to the mRNA vaccines from Biontech, Moderna and the vector vaccine AstraZeneca will soon stand too Novavax and Valneva to disposal, reports echo24.de*. But with which vaccines can the best booster effect be produced? Which combination protects best against the virus – and which does not?
As numerous studies have already shown, so-called cross-vaccinations lead to a particularly strong immune response. But with which two vaccines can the best values be achieved? A British study has now dealt with the topic. The results were published in the oldest and most prestigious medical journal The Lancet released.
Large booster study with Biontech, Valneva and Co.: A combination surprises
According to the report, British researchers launched the COV Boost study, “A Phase 2, Multicenter, Randomized, Controlled, Third-Dose Booster Trial Against COVID-19” accomplished. The vaccines involved as boosters: Astrazeneca, Biontech/Pfizer, Johnson & Johnson, Moderna, Novavax, Valneva and CureVac.
reactogenicity and immunogenicity
By definition, reactogenicity is the ability to evoke reactions. It is about the expected vaccination reactions. Immunogenicity is the ability of an antigen to trigger an immune response (immunization, sensitization).
The COV-Boost study: Almost 3,000 participants in 13 groups
In order to obtain the desired data, the reactogenicity and immunogenicity of the seven vaccines listed were evaluated as the third dose after dual vaccination with AstraZeneca or Biontech. The participants in the study were all over 30 years old and “at least 70 days after two doses of ChAd (AstraZeneca) or at least 84 days after two doses of a Biontech primary COVID-19 vaccination course with no history of laboratory-confirmed SARS-CoV-2 infection”. 2,878 people were involved. Around half were over 70 years old.
The participants were then divided into 13 experimental and control groups, in which they received either the various booster vaccines in full or half doses or a placebo. A total of 20 booster combinations could be tested.
Booster study on Valneva and Co.: The best combinations
In a summary of the study by the Focus says the results: “For the assessment, the researchers determined by which factor the antibody titers had increased 28 days after the booster vaccination. So the highest factor does not necessarily mean which combination provides the best protection – it also depends on how high the antibody level was after the second vaccination.”.
According to the study, the highest increase in antibodies was in the combinations:
Astrazeneca | Moderna Booster |
Biontech | Moderna Booster |
Biontech | Johnson&Johnson booster |
Biontech | Astrazeneca Booster |
In the study on the best vaccine-booster combinations COV-Boost, a double vaccination with AstraZeneca in combination with Moderna achieved a factor of 32.2. The Moderna booster with a factor of 11.5 was the best fit for double corona protection with Biontech.
A booster combination disappoints: bad result for inactivated vaccine
The COV Boost study showed that essentially all booster vaccinations lead to an increase in the immune response. With a vaccine, however, the researchers did not come up with a good value. The result was quite surprising. As from the report of The Lancet becomes clear, a booster with the inactivated vaccine Valneva has the lowest effect in all combinations.
Valneva is currently awaiting approval for Europe. In a recent study, the French biotechnology company came up good efficacy results. Also the side effects of Valneva were examined. However, the vaccine does not seem to come into question as a possible booster alternative.
Booster study with Valneva, Novavax and Co. is not a recommendation
According to the im The Lancet presented study from England, half a dose of Valneva after a double vaccination with AstraZeneca achieved an antibody increase of only 1.8. For a full Biontech vaccination, the value was only 1.3. However, the researchers emphasize that the result has nothing to do with the safety of the vaccine.
Again Focus writes in a contribution to the COV Boost study, the data obtained should not be taken as a general recommendation. The results have a “hook”. According to the article, they describe the antibody response and not generally the effectiveness of the vaccines in relation to infection or disease. The study is limited to double vaccinations with Biontech and AstraZeneca.
There are also differences between the study and the current guidelines in Germany with regard to the intervals between the second vaccination and the booster. For the tests, the booster was available after three months at the latest, in Germany the refresher is currently only available after six months, but after five months at the earliest. *echo24.de is an offer from IPPEN.MEDIA
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