This probably does violate the 20 year-rule, so apologies that I'm going to quote a paper from 2015. Bacteriophage research is not unknown in Western Europe and the Americas, but was largely unused as a treatment modality due to the efficacy and safety profile of antibiotics. With increasing antibiotic resistance, bacteriophages have been often cited as a possible alternative. Despite decades of use in Russia, Georgia, and Poland, phage therapy has not migrated to the rest of the world. An international conference was convened in 2015 to perform a root cause analysis for the reasons for this slow uptake, and to identify possible remedies. The top four causes were identified as:

1) Lack of evidence. Despite the frequency of use in former Soviet nations, there are no randomized controlled trials of bacteriophage therapy, only case reports and case series.

2) Lack of a regulatory and safety system. Antibiotic therapy has a century-old monitoring and reporting system available. Nothing exists for bacteriophage use. There are no professional guidelines for their usage as well, such as from the IDSA (Infectious Disease Society of America)

3) Lack of awareness with the greater public

4) Lack of ability to protect intellectual property. As phages are naturally occuring, it is unclear if pharmaceutical companies would be able to monetize them -- unfortunately a huge trigger for drug development in the Western world.

Recently, phase I and phase II clinical safety trials have been completed (showing an acceptable safety profile), most notably PHAGOBURN for E. coli and Pseudomonal wound infections. No phase III trials have yet to be completed -- but as soon as they do, if they show a benefit, I suspect that all four of these roadblocks will start to crumble. And if they don't, the status quo will remain (though there will still be exciting "what if" Youtube videos).