And for the record too, I believe there had been no successful vaccines ever made that targets coronaviruses... Purely due to the insidious nature of these viruses that enable them to use MULTIPLE protein receptors as entryways to their host cells. After the SARS-COV-1 outbreak in 2003, the Chinese government had spent a whopping sum of money trying to create a vaccine for it. It was a flop and even they had to admit it. We have been lucky that most coronaviruses tend to be benign and do not act like ebola or lyssaviruses... Otherwise we'd be fucked...
On the other hand, US-NIH officially listed hydroxychloroquine and zinc as effective immediate treatments for serious coronavirus infections in 2005... Around the same time that the Chinese vaccine research program failed. Like bactetial infections, active treatment, symptom management, and aggressive immune boosting seems to be the key to reducing mortality rates from coronavirus illnesses. Influenza falls into this same category.