Our pipeline

Our pipeline 

Developing biotherapies based on keystone single-strain bacteria is the game-changing and unique strategy adopted by YSOPIA Bioscience.

Our single strain biotherapies are dedicated to unlocking the therapeutic value of Christensenella, as well as other keystone microbiome bacteria.

> Discover our approach

Thanks to our agile academic partnerships strategy, we are exploring additional therapeutic areas with high unmet medical needs, such as oncology.

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Yso1 is a clinical stage development program aiming at harnessing the potential of Christensenella minuta as a groundbreaking biotherapy to treating obesity and metabolic disorders. 

The goal of our disruptive approach is to return to obese patients christensenella, which have the unique ability to repair the unbalanced microbiome, thereby restoring impaired key functions.

This program is built on first-in-class scientific publications that have identified christensenella as a keystone of healthy human intestinal microbiota. The bacterial strain specifically selected for this program comes from YSOPIA Bioscience proprietary library. 
Yso1 showed strong preclinical efficacy results in preclinical animal models.

By finalizing the industrialization process for the manufacture of clinical batch of its Xla1 product candidate, YSOPIA Bioscience accomplished a key challenge in the production of anaerobic gut bacteria. 

In December 2020, YSOPIA announced the enrollment and treatment of first volunteers in Phase 1 clinical trial under FDA regulation.

Read enrollment and treatment of first volunteers press release

In April 2021, YSOPIA published a scientific article demonstrating that the novel strain C. minuta DSM33407 limits body weight gain in a diet-induced obesity mouse model and normalizes several metabolic markers.

We also addressed the mode of action of C. minuta DSM33407 and suggest it acts as a keystone bacterium, carrying unique functions to restore gut microbiota diversity in individuals with obesity, maintain gut epithelium integrity, and limit adiposity.

Learn more about the publication

Yso2 & Yso3

Yso2 & Yso3 are development programs leveraging the potential of beneficial bacteria such as Christensenella by developing single strain biotherapies to treat patients suffering from inflammatory diseases

Many inflammatory disorders have been associated with alterations of the gut microbiome. YSOPIA Bioscience therefore focusses on restoring the gut microbial symbiosis specifically altered in some inflammatory pathologies using carefully selected single strain bacteria.

Our approach is supported by compelling epidemiological and clinical data that have demonstrated a strong link between the presence of keystone bacteria and reduced risks of developing inflammatory bowel disorders.

Our programs aim at selecting single strain bacteria with a significant anti-inflammatory activity for multiple indications. We expect that at least one clinical candidate will complete IND filing by end of 2021.

We are closely collaborating with Pr. Philippe Langella and his team, from the Micalis Institute (joint research unit between INRA, AgroParisTech and Paris-Saclay University), a cutting-edge European microbiology research organization.

Read our press release

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General review of gut microbiome changes in IBD showing consistant association between CD and a loss of Christensenellacea
Pittayanon, R., Lau, J.T., Leontiadis, G.I., Tse, F., Yuan, Y., Surette, M., and Moayyedi, P. (2019). Differences in Gut Microbiota in Patients With vs Without Inflammatory Bowel Diseases: a Systematic Review. Gastroenterology 1–52.

Important paper showing that loss of Christensenella is predictive of CD flare.
Braun, T., Di Segni, A., BenShoshan, M., Neuman, S., Levhar, N., Bubis, M., Picard, O., Sosnovski, K., Efroni, G., Farage Barhom, S., et al. (2019). Individualized Dynamics in the Gut Microbiota Precede Crohnʼs Disease Flares. Am. J. Gastroenterol. 1–10.


Yso4 is an exploratory program targeting the gut-brain axis for the treatment of mood disorders.

Over the last 5 years, there has been increasing evidence that the gut microbiome was associated with neurological and behavioral disorders, which led to the so called “gut-brain axis” concept.

Multiple complex mechanisms of action are at play in this relationship, and although a lot still to discover, there is strong support for an action of the gut microbiome on neurotransmitter and neuroinflammation.

YSOPIA Bioscience is therefore initiating research in this exciting area to harness the potential of carefully selected bacteria strains of Christensenellaceae to treat mood disorders, such as depression or anxiety.

In April 2020, YSOPIA Bioscience entered into an exclusive license agreement with Spanish National Research Council (CSIC), for its patent application dedicated to the therapeutic use of Christensenella gut bacteria in mood disorders

Read our press release

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Pr. John Cryan, a neuropharmacologist and microbiome expert from the University College Cork, shares surprising facts and insights about how our thoughts and emotions are connected to our gut.

Discover John Cryan on TEDMED

Microbiome & us
Jul 6, 2021
YSOPIA Successfully Completes Phase 1 Clinical Study of Xla1 Biotherapy for the Treatment of Obesity and Metabolic...
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Jun 1, 2021
90 seconds to learn more about YSOPIA Bioscience | [video width="1080" height="1080"...
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Press / Media
Sep 13, 2021
The European Medicines Agency (EMA) and the US Food and Drug Administration (FDA) apply an aligned and complimentary...
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Jun 16, 2021
Forte de la découverte de Christensenella, une bactérie naturellement présente dans les microbiotes sains, la...
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Sep 1, 2021
Héloïse Tudela, Sandrine P. Claus and Maya Saleh Access the full paper The community of the diverse microorganisms...
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Aug 11, 2021
Jeanne-Céleste Paquet, Sandrine P. Claus, Magali Cordaillat-Simmons, Wilfrid Mazier, Georges Rawadi, Laure Rinaldi,...
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A new review article published in the journal JAMA Psychiatry is suggesting a number of different psychiatric disor… t.co/deSy0oKRFj

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