Provided are antibacterial phages that selectively kill bacteria having a resistance gene or the like. Antibacterial phage for this includes CRISPR-Cas13a with a target sequence that recognizes a specific gene as a target. This target sequence is designed as a spacer sequence for crRNA of 14-28 bases. Specific genes are drug resistance genes and toxins. The drug resistance genes are included in bacterial genomes and/or plasmids having one or any combination of the group including: methicillin-resistant Staphylococcus aureus, vancomycin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, penicillin-resistant pneumococcus, multidrug-resistant Pseudomonas aeruginosa, multidrug-resistant Pseudomonas aeruginosa, carbapenem-resistant Pseudomonas aeruginosa, carbapenem-resistant cephalosporins, third-generation cephalosporin-resistant Pseudomonas aeruginosa, third-generation cephalosporin-resistant E. coli, and fluoroquinolone-resistant E. coli.

The present invention relates to a phage or a composition that comprises it, wherein said phage expresses at least one specific recognition element and is furthermore conjugated with at least 300 molecules of a sonosensitiser. The invention further relates to the use of said phage in a sonodynamic therapy.