[M95D]

That's only partly it.

The whole procedure of selecting a phage personalized for the patient and then growing it into a treatment is so slow the patient may die before it's ready. Works for chonic infections but not much else.

There are probably phage treatments that are not personalized: test susceptibility and then mail-order the treatment. That treatment:

  - Would be very expensive to *produce* compared to most antibiotics. I emphasize *produce* because the price of antibiotics rarely reflect how much it costs to produce them. Compared to antibiotics, phage treatments have very low margins.

  - Would work for a very limited percentage of patients (probably less than 10%). There are hundreds of phages for each bacteria species (yes, they're species-specific and sub-species-specific). 

  - Have a very *very* short shelf life, possibly a couple of days. So, no pharmacy or hospital can keep a sufficiently diverse supply of phages in store to treat most patients, possibly not even whole countries.

BTW, species specificity and shelf life applies to the susceptibility test kits too.

[looofooo0]

Well Phage guard and similar products using a replacement schedule and many phages in one cocktail. But this does not mean that page guard like products would not be successfully as medicine, but as a medicine this is not possible as it is non-stable and containing live viruses. At best, you would need to get a new approvable every time the cocktail changes.