Bacteriophage or phage therapy is the therapeutic use of bacteriophages to treat pathogenic bacterial infections, a therapy which has been used extensively in former Soviet Union countries for over 90 years.
There is no evidence to suggest that the introduction of additional organisms with their DNA and RNA could have any long-term benefit.
Indeed, the horizontal gene transfer of DNA and RNA between organisms represents the primary mechanism by which the microbiota causing Th1 disease accumulates its pathogenic capability. Adding new pathogens only increases statistical risk: the practice might reduce overall pathogenicity or it might increase it.
Some patients do experience improvement of symptoms during an acute infection, but not cure. In the long run, the extra pathogens can only present more problems.