Synthetic biologists are developing an attenuated version of SARS-CoV-2 for use in a vaccine, Technology Review reports. It adds that Codagenix is working with the Serum Institute of India, a large vaccine maker.
According to Tech Review, an attenuated form of SARS-CoV-2 can be generated by developing a "de-optimized" form that has numerous mutations introduced into it that lead it to depend on less reliable codons. That change, it says, slows the virus' ability to replicate and makes it be less efficient at infecting someone.
As Tech Review notes, SARS-CoV-2 vaccines currently in late-stage testing — such as those from AstraZeneca and Moderna Pharmaceuticals — only expose recipients to part of the virus, to try to generate an immune response. Exposing people to an attenuated SARS-CoV-2 could elicit a more complete immune response, it notes. "If you want to complete the immunological response, then you need to mimic the course of the disease," Rajeev Dhere from the Serum Institute tells it.
But the Scripps Research Institute's Michael Farzan tells Tech Review that using an attenuated version of SARS-CoV-2 isn't needed. "You only need live attenuated viruses when you don't have a safer one," he adds there. "In this case it brings a risk that is unnecessary."