How would COVID-19 vaccine manufacturers adapt to the new variants?
Modifying the drug, a process that should be easier than creating the original.
Viruses constantly mutate as they spread, and most of these changes are not significant. First-generation vaccines appear to be working against known coronavirus variants today, but drug companies are already taking steps to update their prescriptions if health authorities decide it is necessary.
The vaccines developed by Pfizer-BioNTech and Moderna are made with new technology that is easy to update. The so-called messenger RNA (mRNA) vaccines use a fragment of the genetic code of the spike protein that covers the coronavirus so that the immune system can learn to recognize and fight the real one in case of contagion.
If a variant with a mutated spike protein that the original vaccine cannot identify, the drug companies would have to modify that genetic code for another that fits more closely if regulators decide it is necessary.
Updating other vaccines could be more complex. The one from AstraZeneca and the University of Oxford, for example, uses a harmless variant of a flu virus to deliver the gene for that spike protein into the human body. A patch would require creating another virus with the updated gene.
The US Food and Drug Administration said studies of updated vaccines will not have to be as large as those of the first generation. Instead, a few hundred volunteers could receive experimental doses of the new one and undergo a blood test to determine if it upgraded its immune system, as it does with the former.
More difficult is deciding whether the virus has mutated enough to modify the drug.
Health authorities around the world will monitor coronavirus mutations for vaccine-resistant alterations. In addition, they will have to decide whether a modified vaccine should protect more against a certain variant.
In general, the process would be similar to what already occurs with the influenza vaccine. These viruses mutate much faster than coronaviruses, so flu vaccines are adjusted every year and must protect against various strains.
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