I believe there are some Biotech companies beginning to engineer their own bacteriophages in order to use CRISPR-Cas 9 genome editing to kill target bacterium.
Development of phages can actually turn the bacterial immune system known as CRISPR against itself. Phages target the resistant bacteria, and then the CRISPR system incorporates the DNA with specific instructions for a modified guide of RNAs which hone in on part of an antibiotic-resistance gene. Once that phage, then infects a bacterium, the guide RNA latches on to the resistance gene, which prompts the enzyme, Cas3, to destroy the genetic sequence instead. Cas3 eventually destroys all the DNA, killing the bacterium altogether.... So we are seeing phages beginning to be used more frequently in the mechanics behind the CRISPR-Cas9 gene-editing system.
Hope this answered your question-- keep steeming my friend :)