I had a little bit about that in med school. Interestingly the largest phage therapy center was (is?) in Georgia. This method was often used for resistant skin

I had a little bit about that in med school. Interestingly the largest phage therapy center was (is?) in Georgia. This method was often used for resistant skin infections with e.g. Staphylococcus aureus, so the application was generally topical. There were also attempts at intravenous administration of phages, but I am not sure about safety concerns there (rapid lysis of bacteria resulting in a toxic shock, excessive antiviral response of the immune system and purification of phages all come to mind).