https://www.scientificamerican.com/article/the-second-generation-covid-vaccines-are-coming/

Six months ago, as the northern hemisphere was still battling the coronavirus pandemic’s first wave, all eyes turned to the COVID-19 vaccines in late-stage clinical trials. Now, a year after the pandemic first erupted, three COVID vaccines have been given emergency authorization by either the U.S. or U.K., as well as other countries. Two of the vaccines, developed by Pfizer and BioNTech and Moderna, respectively, both employ a novel genetic technology known as mRNA. And the third is a more conventional vaccine developed by the University of Oxford and AstraZeneca that uses a chimpanzee virus to deliver DNA for a component of SARS-CoV-2, the virus that causes COVID. (Russia, China and India have rolled out their own vaccines, but with the exception of a few countries, they have not been widely authorized elsewhere.)

But impressive as they are, these vaccines alone will likely not be sufficient to end the pandemic, experts say. Luckily, there are hundreds of other COVID vaccines under development—including many with new mechanisms of action—that could prove to be effective and cheaper and easier to distribute.