PHOSAClin: clinical phase of application of phagotherapy to combat staphylococcus aureus infections of the diabetic foot


The diabetic foot is one of the most common complications of diabetes, in which damages to the peripheral nerves and the decrease of the natural hydration of the foot cause ulcerations and a destruction of the tissues.

Alarming estimates

More than 3 million people are affected by diabetes in France and more than 170 million worldwide. This figure is constantly growing.

It is estimated 1 that about 15% of these people will be affected by diabetic foot ulcers during their lifetime (25% for the OECD2, in some areas).

This is a serious complication with a pessimistic prognosis for the patients affected: their mortality rate is multiplied by 2 3 compared to unaffected diabetic people.

Infections difficult to fight off

The lack of oxygenation of the foot leads to slower healing and an increased risk of bone and / or joints infections.

These infections, most often due to a bacterial strain of Staphylococcus aureus, are usually treated with antibiotics.

But the increase of bacterial resistance, combined with the formation of bacterial biofilms4 and the poor diffusion of antibiotics in bone tissue, lead to a real therapeutic stalemate.

Phagotherapy, a promising alternative

Thanks to the PHOSA project, conducted by Pherecydes Pharma from 2014 to 2017, phagotherapy turned out to be an alternative or complementary solution to diabetic foot infection. This project focused on the development of a S. aureus bacteriophage cocktail and its pre-clinical evaluation.

As for PHOSAClin, it aims to evaluate these phages in a large scale clinical study.

The aim is to evaluate the tolerance and efficacy of PHOSA bacteriophages in humans, with the following objectives:

  • production of the cocktail clinical lot under GMP5 conditions;
  • conducting the first in-man clinical trial (phase I / IIa);
  • analysis of results;
  • preparation of the next phase IIb / III clinical trial;
  • preparation of the demand of an Autorisation Temporaire d'Utilisation (ATU6)

The PHOSAClin project is partly financed by an aid to innovation by bpifrance.

1 Nunan, R., Harding, K. G., & Martin, P. (2014). Clinical challenges of chronic wounds: searching for an optimal animal model to recapitulate their complexity. Disease Models and Mechanisms, 7(11), 1205-1213
2 OECD Indicators - Health at a Glance 2013
3 Chammas, N. K., Hill, R. L. R., & Edmonds, M. E. (2016). Increased Mortality in Diabetic Foot Ulcer Patients: The Significance of Ulcer Type. Journal of diabetes research
4 system for protecting bacteria, especially against antibiotics
5 Good Pharmaceutical Manufacturing Practices
6 Authorization for Temporary Use