"I do not believe that there has ever been a successful vaccine developed for a coronavirus caused disease."

No, but that's partly because funding for SARS vaccines was pulled when SARS went away. We don't know whether a successful SARS vaccine could have been created, and if it had, we'd likely have a vaccine for this one by now.

Some Germans have claimed that an existing drug that's used in Japan for a different illness seems to significantly reduce the impact of this virus by preventing it from spreading in the body. So if it goes into decline for the summer and comes back in the winter we may at least have an effective treatment by then which doesn't require ICU care.