Landflap
Depends what yo mean by 'works'!
With the respect to the misinformation posted above, yes, all 'work' by potentiating a host immune response that targets the SAR-COV2 virus. I am sure. I promise.
Of course some achieve that work by 'working' in a different way. Some are very traditional vaccines based on inactivated virus, others use novel mRNA methods, and there are at least 2 technologies that fit somewhere in between along that spectrum. But all target the virus. I don't know of any that target the COVID-19 disease process - although that is not impossible and someone may well be working on it. Certainly immune modulation is a route for therapy.