In Saint-Quentin-Fallavier, near Lyon, on the edge of the A43, a very special kind of factory has just been built. In this building with immaculate walls, the fresh stools of hundreds of people will soon be delivered in small airtight boxes to be transformed into real medicines. These treatments developed by the French company MaaT Pharma created in 2014 on the basis of a technology transfer with INRAE are at the forefront of innovation and in the midst of a revolution. They exploit the numerous properties of the intestinal microbiota – all the microorganisms present in our intestine – to tackle the most severe diseases in the field of oncology.

The promises are so great that a move to industrial production has become essential as demand is expected to explode in the coming years. “We produce drugs that modulate the microbiota to modulate immunity. Studies show that this improves patient survival,” explains Hervé Affagard, CEO and co-founder of MaaT Pharma. In certain illnesses, this treatment is curative, that is to say that it alone allows for healing. In other cases, it improves the effectiveness of treatments: for example, chemotherapy or immunotherapy that uses the immune system to fight cancer cells.

The company also has several clinical trials underway with two of its products. The first, MaaT013, is a 150-milliliter bag containing stool solution from four to eight carefully selected donors. The liquid is administered rectally. Mixing several donations in this way increases the diversity of the microbiota and standardizes it, which improves the effectiveness of the treatment and its reproducibility. “Each pouch contains approximately 500 species of bacteria, while an individual donor harbors between 150 and 300,” explains Carole Schwintner, director of technology.

MaaT013 is currently in phase III of a clinical trial – a phase which precedes marketing authorization – carried out on 75 people and targeting graft-versus-host disease which can occur after a stem cell transplant indicated to treat certain blood cancers. “This disease is very serious. The graft turns against the patient and will attack the skin, liver and intestine. In the latter case, we can have 80% mortality at one year. But here, the administration of microbiota can be curative,” assures Émilie Plantamura, director of clinical development.

If the tests are conclusive, the product could arrive on the market in 2025-2026. The second trial with MaaT013, currently in phase II on 60 people, aims to improve the effectiveness of the treatment of metastatic melanoma. The product complements immunotherapies which, in some patients, do not work at all. “Many studies have shown that this lack of response could be linked to the microbiota. The aim of this second trial is therefore to increase the effectiveness of these immunotherapies, because MaaT013 stimulates the immune system,” explains Émilie Plantamura.

The Lyon-based company also uses artificial intelligence to develop new products. It has developed a platform based on machine learning which analyzes all the data already collected during trials or still available in the scientific literature, in order to identify and manufacture the best microbiota against this or that disease. This approach is still very experimental and no product is in the clinical trial phase. But when the time comes, the factory will be able to industrially produce the ideal microbiota for a given disease, thanks to an assembly of stools from several donors. Like a cellar master who juggles with grape varieties to produce a grand cru.