>Using a bacterial vaccine to treat primarily inoperable sarcoma, Coley accomplished a cure rate of better than 10%.
This was, of course, miraculous at the time, and doesn't look too bad compared to the best treatments today for advanced cancer. However, the efficacy would have to increase significantly for most people to get excited, I think.
Perhaps as an adjuvant to targeted therapies? The Wikipedia article doesn't mention side effects. However, considering the mechanism of action, they might not have been too bad.