What happened to our dreams of phage?

I want to talk about bacteriophages and more specifically phage therapy, that is using phages to treat bacterial infections. While I have known about phages for several years, I’ve only recently gained enough knowledge in biochemistry to better appreciate the elegance of the solution they provide. Simply put bacteria evolve, chemicals (antibiotics) don’t. A changing threat requires an adaptive solution.

I will not go into the details, except to say that phages are just viruses that infect specific bacteria. Similarly, the full history of phage therapy is long and interesting but beyond the scope of this post.

Back in 1997 the BBC program Horizon (episode “The Virus that Cures”) introduced many people to phage and sparked much interest in the West. So here we are 11 years later and it seems that very little has happened. So where did things go wrong?

First it must be realized that a phage is VERY specific in which bacteria strain it targets. This property is very useful medically but very problematic for companies looking to deploy phage based treatments. The specificity leads to two possible types of treatment:

  1. The first would be a highly personalized approach where the particular strain affecting a patient is determined and a phage collection is checked to see if there is an existing phage which targets that particular bacteria. If the matching phage is not in the existing collection, a new lytic phage must be found, although this could take quite some time.
  2. The second option is to just create a cocktail of different types of phages for common bacteria, and hope you get lucky. This would probably be very effective for a majority of cases. Of course if your cocktail is ineffective, you would have to go to the personalized approach.

Now it important to note that it is very difficult to get the FDA to approve a cocktail. In the domain of personalized treatments, it is not exactly clear how a company would have to get approval from the FDA (which takes about 12 years on average) if they wanted to treat a single person with a brand new phage. Add to this that fact that single biophages can not be patented and you get a perfect regulatory storm.

My research seems to indicate that several pharmaceutical companies which have tried to test the FDA waters (Targanta Therapeutics [formerly PhageTech] and Exponential Biotherapies) have met with little success. Although the FDA has allowed the use of phages on meat products in the food industry to prevent food poisoning.

So from an investor’s perspective the best policy seems to be just sitting back and waiting for some big changes in FDA regulation. In the mean time it would be a good idea to keep an eye on developments outside the US, particularly on countries with much more relaxed regulation. Depending on the exact change in regulation which will come inevitably, a company’s large collection of phages may go from being just scientifically priceless to a valuable capital asset as well. Of course this change in policy may only come about once the antibiotic resistance situation is way out of control. Until then, the bacteria will divide as they always do and the FDA will sleep as it always does.

Here are the companies I looked at:

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