Exeliom Biosciences: 10 Key Things You Must Know

Overview

Exeliom Biosciences is a dynamic clinical-stage biotechnology company based in Paris, France, focused on developing innovative immunomodulatory therapies primarily targeting cancer, inflammatory bowel diseases, and infectious diseases. Founded in 2016, the company has rapidly gained attention for its lead candidate, EXL01, a first-in-class immunomodulator that harnesses the body's innate immune system through targeting the NOD2 receptor in macrophages. What sets Exeliom apart is its unique approach employing a single-strain live biotherapeutic product derived from the microbiome, innovatively repurposing bacterial components to modulate immunity. This article explores ten key facets of Exeliom Biosciences, shedding light on its science, clinical progress, funding, and the therapeutic promise it offers.

1. Foundation and Vision

Exeliom Biosciences was founded in 2016 by a team of leading scientists including Prof. Harry Sokol and Dr. Philippe Langella in Paris and Dijon, France. The company's core mission revolves around transforming scientific innovation into transformative therapies, with a particular emphasis on giving patients a fair chance to fight complex immune-mediated diseases. By leveraging cutting-edge microbiome science and immune biology, Exeliom aims to develop next-generation immunotherapies that improve outcomes in areas where traditional treatments often fail.

2. The Lead Candidate EXL01

At the heart of Exeliom's pipeline is EXL01, a first-in-class immunomodulator designed to activate NOD2 receptors on macrophages, driving a metabolic reprogramming in immune cells that results in precise and powerful immune modulation. EXL01 is derived from Faecalibacterium prausnitzii, a beneficial gut bacterium, and functions as a single-strain live biotherapeutic product administered orally. By targeting the NOD2 pathway, EXL01 influences macrophage activation and polarization, which plays a pivotal role in immune responses against cancer, inflammation, and infections.

3. Understanding the NOD2 Pathway

The NOD2 receptor is an intracellular pattern recognition receptor that detects bacterial peptidoglycans, key components of the microbiome. NOD2 is a master regulator of innate immunity, controlling macrophage activation states between pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes. Dysregulated NOD2 signaling has been implicated in a variety of diseases, including Crohn's disease, certain cancers, and chronic infections. Exeliom’s approach to modulate this receptor precisely unlocks new therapeutic avenues that conventional drugs are yet to explore.

4. EXL01’s Clinical Trial Progress

EXL01 is currently in multiple Phase 2 clinical trials across several disease indications. It is evaluated in oncology for cancers such as gastric cancer, non-small cell lung cancer (NSCLC), hepatocellular carcinoma (HCC), and renal cell carcinoma (RCC), typically in combination with immune checkpoint inhibitors. In addition, EXL01 is undergoing trials for inflammatory bowel disease, specifically Crohn’s disease, and recurrent Clostridioides difficile infections. Early Phase 1 studies have shown a robust safety profile, supporting its further clinical development.

5. Innovative Live Biotherapeutic Approach

Rather than relying on traditional small-molecule drugs or antibodies, Exeliom utilizes a live bacterial strain to deliver its immunomodulatory effects. EXL01’s design is gastro-resistant, ensuring the active compound releases specifically in the jejunum and ileum, facilitating targeted immune activation without the need for gut colonization. This microbiome-based methodology represents an innovative frontier in immunotherapy, blending microbiology with precision medicine.

6. Financial Backing and Funding Milestones

Since its inception, Exeliom Biosciences has raised close to €30 million through a combination of dilutive and non-dilutive funding sources. The company completed a notable €24 million Series A financing round in 2023, with a further €2.85 million extension in 2025 led by investors including Biocodex, Crescent Ventures, UI Investissement, and Forepont Capital Partners. These funds are strategically targeted to accelerate EXL01’s clinical development and support expansion into international markets, including the United States.

7. Partnerships and Collaborations

Exeliom has cultivated scientific and clinical partnerships that bolster its research pipeline. Collaborations include working with institutions such as Hospices Civils de Lyon and participation in the REMIND network, a consortium of French gastroenterology departments. These partnerships focus on clinical trials in immuno-inflammation and immuno-oncology, enabling Exeliom to access diverse patient populations and cutting-edge expertise in disease management.

8. Tackling Cancer with Immunotherapy

Exeliom’s therapeutic strategy in oncology is to use EXL01 to reprogram the tumor microenvironment, stimulating macrophages to overcome immune resistance often seen in cancer patients. By combining EXL01 with immune checkpoint inhibitors, the company aims to enhance the efficacy of existing immunotherapies. Significantly, the ongoing Phase 2 gastric cancer study is the largest randomized bacterial therapy trial in oncology worldwide, highlighting Exeliom’s leadership in this emerging field.

9. Broader Impact on Immune-Mediated Diseases

Beyond cancer, Exeliom is pioneering treatments for immune-mediated diseases such as Crohn’s disease and recurrent Clostridioides difficile infections, conditions characterized by dysregulated immunity and persistent inflammation. EXL01’s ability to finely tune macrophage polarization offers a novel mechanism to restore immune balance and promote tissue repair, addressing unmet needs in these chronic, hard-to-treat diseases.

10. The Future Outlook for Exeliom Biosciences

Looking ahead, Exeliom is focused on completing its ongoing clinical trials and preparing for regulatory approvals that could bring EXL01 to patients globally. The company plans to expand its cancer clinical program to the US and further explore new indications unlocked by its NOD2-targeting immunomodulator. With growing investor confidence and a strong scientific foundation, Exeliom Biosciences is positioned to be a trailblazer in microbiome-based therapies with the potential to transform treatment paradigms across several major disease areas.

Conclusion

Exeliom Biosciences exemplifies the intersection of innovative science and clinical ambition, leveraging the human microbiome and immune system to develop transformative therapies. Its lead candidate EXL01 offers a unique, targeted approach to modulating innate immunity through the NOD2 receptor, with promising applications in cancer, inflammatory bowel diseases, and infectious diseases. Supported by robust funding and strategic partnerships, Exeliom is advancing towards pivotal clinical milestones with the potential to reshape therapeutic landscapes. As our understanding of the microbiome-immune axis deepens, Exeliom’s work raises exciting questions about the future of precision immunotherapy and how harnessing microbes can unlock new frontiers in medicine.