For weeks, pharmaceutical companies have been investigating whether they need to adapt their vaccines to the ever faster spreading coronavirus variant Omikron. The vaccines were originally developed against the so-called wild type of Sars-CoV-2, which was first discovered in China at the end of 2019. While the agents used since the turn of the year 2020/2021 also showed their effect against later virulent mutants such as Alpha or Delta, it could look different with Omikron.
How does Omikron differ from the other variants?
Compared to the original wild type, Omikron shows more than 30 mutations, especially in the spike protein with which the virus enters human cells. Some of these mutations are also present in other variants – for example at Alpha, said Biontech founder Ugur Sahin recently. But the earlier variants only showed around 10 to 15 mutations. These changes at Omikron could have the effect – according to the fear – that the previous vaccines against an infection are less effective and that the antibodies formed in the body after a vaccination are insufficient.
Researchers see indications that Omikron is more contagious than the Delta variant currently prevalent in Germany.
Since when has a vaccine update been researched?
Above all, the manufacturers of the mRNA preparations, Biontech / Pfizer and Moderna, have been advertising since the beginning of their first-time vaccines with the possibility of being able to adapt them quickly to virus changes. Both have been preparing their funds for possible mutations of the coronavirus for months – including with clinical examinations. “These studies have shown that variant vaccines are equally well tolerated and show symptoms similar to the original vaccine against the wild type,” said Sahin.
The US manufacturer Moderna began adapting its mRNA vaccine specifically against the Omikron variant at the end of November. “We have multivalent candidates who have already been optimized for earlier variants such as beta or delta and who are already in clinical testing,” said Germany managing director Gerald Wiegand of the German press agency. “Data has already come together.”
The manufacturer Astrazeneca also claims that it has taken the first steps together with researchers from Oxford University to produce an omicron vaccine in the event that it is needed. There was initially no time information.
When can an omicron vaccine be expected?
According to the company, Biontech already creates the prerequisites for being able to manufacture the product quickly. The production process does not differ from that for the previous product, it said. Company founder Özlem Türeci recently assumed that the first commercial batches of a special Omikron vaccine could be available in March – and then millions of them.
With regard to the preliminary study results, however, Türeci limited: “These are not a basis for making preventive decisions about the need for a vaccine adapted to Omikron. We have to evaluate further laboratory data and, above all, data from practice that is expected in the next few weeks will.” Only then will it be shown how things will continue.
Wiegand also emphasized that it had not yet been decided whether and when Moderna would bring an Omikron-specific booster onto the market. “The action is very dynamic.” Wiegand pointed out that a booster vaccination with the currently approved preparation from Moderna could increase the antibody level against Omikron – depending on the dose – by up to 83 times. “That is a sharp sword. But it is not yet possible to say whether that is enough to fight Omikron.”
How do the manufacturers proceed with the modification of the vaccine?
“The moment the genetic information about a virus variant is available – that was it at the end of November – this information will be adapted accordingly in our vaccine development,” said Wiegand.
At Biontech, according to the company, the blueprint of the spike protein of the new variant is generally determined first, from which the mRNA for the adapted vaccination is created. That takes about six weeks. If their quality characteristics meet all expectations, the funds could come onto the market – provided that official approvals are obtained, said Sahin.
What does Europe’s approval authority say?
The European Medicines Agency (EMA) believes that it is currently too early to decide whether an adapted vaccine with a different composition is even necessary. First, “more data about the effects of the variant on the effectiveness of the approved vaccines” would have to be collected, the EMA informed the German press agency. There is also a need for more information on transferability and mortality at Omikron. Biontech and Pfizer recently announced that, according to preliminary laboratory results, three doses of their previous product would provide sufficient protection against serious illnesses following an Omicron infection. If the manufacturer does adapt it, the EMA has already made preparations.
How then do the vaccines get to market?
If the modified remedy only contains a slightly different genetic construct than the one that has already been approved, “then only a small clinical trial is required in the EU to change the original approval,” explained the President of the Paul Ehrlich Institute, Klaus Cichutek, recently in an interview with New Osnabrück newspaper. In such a case, the changes in the genetic material and in the manufacturing process would be examined.
According to their own statements, Biontech and Moderna are already in constant contact with the approval authorities. “It is still too early to make a clear forecast,” said Wiegand.
How does the admission process then?
Since February there has been an EMA guideline describing the requirements for manufacturers if they attempt to adapt their vaccines due to new virus variants. If the mother vaccine has already been approved, the modified active substance does not have to go through the entire process again. A clinical series of tests on the effectiveness with a small number of test subjects is sufficient, it is said.
Will the vaccination then start all over again?
“The current concepts are going in the direction of examining the possibility of boosting,” emphasizes Moderna’s Germany boss Wiegand. Booster vaccinations are a “common approach” not only for Covid-19, but also for other infectious diseases. This means that there could be a further booster vaccination for the vaccinations against the corona wild type that have already been carried out, which is specifically aimed against the new variant in each case. Fears widespread by opponents of vaccinations on various social media channels that vaccination series with three new vaccinations against Omikron are planned are therefore unfounded.
(kbe)