The European Medicines Agency EMA has spoken out in favor of the use of two Omicron vaccines. These are the vaccines from Moderna and Biontech/Pfizer, both of which contain the original vaccine plus a component adapted to the omicron variant BA.1. They are called bivalent because of their dual purpose.
Both vaccines are intended as boosters. Moderna’s product can be used for adults, while Biontech’s preparation can also be used for children and adolescents from the age of twelve according to the application for approval. Federal Health Minister Karl Lauterbach (SPD) announced a few days ago in a letter to those involved in the vaccination campaign that the boosters with these vaccines can begin quickly.
First of all, the European Commission still has to agree, which, however, is considered a formality. Assuming this, the first doses could be administered from next week. According to Lauterbach, around 14 million doses are available for the first two weeks. The Standing Vaccination Committee (Stiko) must clarify who should be vaccinated with the new preparations. Lauterbach said on Thursday in the ARD morning show that the panel of experts wanted to present its assessment a week after approval.
The Stiko will probably recommend the adapted boosters especially for older people
Carsten Watzl, Secretary General of the German Society for Immunology, assumes that the vaccines will continue to be recommended as a second booster only for certain population groups, especially those over 60 and those who have previously been ill. “I would be very surprised if the Stiko said that all adults should be vaccinated again,” he told the dpa news agency.
The two Omikron vaccines had each been tested on several hundred people. It was examined how much they increase the amount of those antibodies that prevent the virus from entering the human cell. The amount of these neutralizing antibodies was about 1.6 to 2 times that after administration of the conventional vaccines alone. However, these values only refer to the omicron subvariant BA.1. It no longer plays a role in Germany, 95 percent of the infection process here is determined by subvariant BA.5.
The antibody titers against this subtype also increased after vaccination with the new preparations, but to a lesser extent than against BA.1: the increase was three times lower than against BA.1. Antibody titers are a surrogate parameter that indicates efficacy in principle. However, it is not possible to derive from them exactly how many infections, cases of illness or deaths can be avoided.
A vaccine specifically directed against BA.5 and the very similar sub-variant BA.4 could also come onto the German market at a later date. At the end of August, Biontech submitted an application for EU approval for such a product. This vaccine received a positive vote from the US Food and Drug Administration (FDA) on Wednesday. Unlike the BA.1 vaccines, it has not yet been tested on humans, only on animals.
Should one wait for a BA.5 vaccine?
For those who want to be vaccinated, the question now arises as to whether they should boost themselves with one of the BA.1 vaccines or whether they should wait for the BA.5 vaccine, which may come on the market later. Immunologist Watzl told the SZ that he was clearly in favor of not waiting. On the one hand, “the BA.1 vaccine is much closer to the current BA.5 variant than the original vaccine. That’s why you have a clear advantage with the BA-1 vaccine.” On the other hand, there are still a number of unanswered questions.
So no one can say how much better the BA.5 vaccine is compared to the BA.1 vaccine. It is also unclear when it will actually be available. If the EMA also requires human studies for approval, the process could drag on until November or December. In addition, it is not possible to predict which variants will prevail in winter. A possible candidate is BA.2.75, for which the BA.1 vaccine would probably be a better fit. However, the BA.4.6 variant is also conceivable, for which the BA.5 vaccine would probably be better. All in all, however, according to Watzl, due to these uncertainties, he cannot recommend anyone who is currently vaccinating to wait for the BA.5 vaccine.
The omicron variant was discovered at the end of last year. Since then it has split into several subtypes. Compared to other variants, these contain significantly more mutations and allow the virus to partially escape the immune response. As a result, the vaccinations are no longer effective. In particular, the protection against infections decreases several weeks to months after vaccination. The protection of conventional vaccines against serious illnesses, on the other hand, is still good. The coming weeks and months will show to what extent the new vaccines will change the situation.