Exeliom's EIC Accelerator Bet on a Crohn's Bacterium, Revisited

Faecalibacterium prausnitzii is one of the most common bacteria in a healthy human gut, and people with Crohn's disease tend to have too little of it. Exeliom Biosciences, a French company founded as Nextbiotix in December 2016, set out to turn a single strain of it into a daily capsule, EXL01, to keep Crohn's patients in remission. In the European Innovation Council's March 2020 EIC Accelerator pilot round it won a grant-only award for that plan: an EU contribution of €2,501,528.75 towards a project costing €3,573,612.50, which was to take EXL01 to "phase 2a clinical trial" and scale up its manufacturing, according to CORDIS.

Six years on, the manufacturing promise has been kept and the clinical one only in part. The first Crohn's trial was a Phase 1 study that dosed its first patient in March 2023, in the project's last month, and was terminated in October 2024 "due to low recruitment" after eight participants. The company has raised more money since, but it has pivoted: its homepage now presents EXL01 first as an add-on to cancer immunotherapy, according to Exeliom's website.

Where Exeliom Stands Now

Exeliom Biosciences is still in business, but it has pivoted: its lead programme is now cancer immunotherapy, not the Crohn's maintenance therapy the EIC funded. The French business register lists it as active with its seat at 7 passage du Chemin Vert in Paris and Benjamin Hadida as président, according to the state company search service, and the official gazette BODACC recorded capital increases in June 2024, May 2025 and February 2026 and the filing of its 2025 accounts in August 2026, according to BODACC notices. In July 2026 the company said the randomised Phase 2 trial of EXL01 in gastric cancer had passed its pre-specified futility analysis and would keep recruiting, according to Exeliom. No insolvency notice appears in the register.

The team is small. Exeliom describes a "core team of seven full-time employees" on its website, and Université Paris-Saclay, home of co-founder Philippe Langella's INRAE laboratory, gave the same figure in a February 2026 profile that counted six clinical trials and about €32 million raised. The CORDIS project summary of 2020 described "a team of 5 operational people".

The Technology: One Strain, Grown Without Oxygen

EXL01 is an unmodified single strain of F. prausnitzii, grown in a proprietary culture medium "under strict anaerobic conditions" and packed into gastro-resistant capsules that release it in the intestine, according to the company's pipeline page. Most Crohn's drugs suppress the immune system; Exeliom's argument is that restoring a missing anti-inflammatory gut bacterium could keep patients in remission with fewer side effects. In laboratory tests the strain raised secretion of the anti-inflammatory signal IL-10 without raising TNF-alpha, the company reports.

The difficulty is the bacterium itself. F. prausnitzii dies in contact with oxygen, and the EXL01 strain "was deemed impossible to manufacture in industrial large-scale conditions" when the project began, Exeliom wrote in its final CORDIS report. Faecal transplants and multi-strain mixtures are the established ways of changing the gut microbiome; a single, defined strain made to drug standards is what lets a regulator treat it as a medicine. Exeliom now explains EXL01's effect through activation of the NOD2 receptor in macrophages, a mechanism it uses to justify trials in very different diseases, according to its company history.

What the EIC Project Promised, and What CORDIS Shows

The European Commission's list of EIC Accelerator pilot winners for the March and May 2020 cut-offs names Exeliom Biosciences of Dijon as the only beneficiary of EXL01, with grant-only funding. The grant agreement was signed on 28 July 2020 and the project ran from 1 August 2020 to 31 March 2023, according to CORDIS. The objective was explicit: "Thanks to the EIC Accelerator, Exeliom will reach phase 2a clinical trial and scale-up its manufacturing process."

The manufacturing half was done. The final report says the company produced what it calls the first large-scale clinical batch of F. prausnitzii drug substance worldwide under Good Manufacturing Practice, made the first clinical batch of capsules and set up its own pilot manufacturing unit. Exeliom announced the opening of that unit in May 2021 and said the EIC grant had "notably" paid for it, in a company post. Its website now says more than 10 GMP batches have been made and the process has been transferred across several production sites.

The clinical half was not. The trial that came out of the project was a Phase 1 safety study, not a Phase 2a trial. It received its first clinical trial authorisation from the Belgian agency in February 2022, and its first patient was enrolled on 20 March 2023, eleven days before the project ended, according to ClinicalTrials.gov and the company's announcement. The CORDIS report said results from the first part were expected at the end of 2023 and from the second at the end of 2025. The second part never ran.

1. Scale up manufacturing of an oxygen-sensitive strainDeliveredGMP drug substance and capsule batches produced, per the CORDIS report; more than 10 GMP batches, per the company.
2. In-house pilot manufacturing unitDeliveredOpened May 2021, per the company and the CORDIS report.
3. Clinical trial authorisation in EuropeDeliveredBelgian approval in February 2022; first patient in March 2023.
4. Phase 2a trial in Crohn's diseaseNot achievedThe project's trial was Phase 1. A Phase 2 Crohn's trial opened in 2025, two years after the project, with an academic sponsor.
5. Efficacy results from Part 2 by end 2025Not achievedPart B "was not performed" because of low recruitment, per the published trial paper.

The Crohn's Trial: Safe, Small and Stopped

The results of that first-in-human trial, MAINTAIN, were published in Nature Communications on 28 April 2026. It was open-label and single-arm, with no placebo group, and enrolled eight adults with mild to moderate Crohn's disease whose symptoms had been brought under control with corticosteroids. EXL01 was "well-tolerated with no treatment-related adverse events". Six participants completed the study and two stopped treatment after their disease flared. The authors found changes in gene expression in the gut lining but a largely stable microbiome, and they state that "due to the low recruitment rate into Part A the study was discontinued early; Part B was not performed."

Exeliom presented the outcome as "positive results" in January 2025, saying the trial met its Part A primary endpoint, safety, and that it had ended the study "reflecting recruitment challenges in the IBD field", according to its announcement. Both statements are accurate. Neither shows whether EXL01 keeps Crohn's patients in remission, which was the claim in the project title.

The Crohn's programme continues in a different design. MAINTAIN-POP, a placebo-controlled Phase 2 trial in patients who have had bowel surgery, opened on 31 March 2025 with a target of 80 participants and an estimated primary completion date of 13 September 2026, according to ClinicalTrials.gov; its sponsor is an individual investigator working with the REMIND group of French gastroenterology departments, not Exeliom. The registry record was last updated in September 2025, and no results had been published by early October 2026.

What Exeliom Has Achieved Since the Award

The biggest change since the award is the shift to cancer. The June 2023 financing was raised "primarily to progress the clinical development" of EXL01 "into two new therapeutic areas: immuno-oncology and infectious diseases", according to the company's release, reprinted by Bionity. In April 2024 Exeliom announced three Phase 2 trials combining EXL01 with immune checkpoint inhibitors in gastric cancer, non-small cell lung cancer and liver cancer, run by GERCOR, Lille University Hospital and the Centre Eugène Marquis in Rennes, in a company announcement. A fourth, in kidney cancer with City of Hope in the United States, followed US Food and Drug Administration clearance in December 2025. A separate trial in recurrent Clostridioides difficile infection runs with the Hospices Civils de Lyon.

The company now calls the gastric cancer trial, BIG, "the lead value inflection point for EXL01" on its pipeline page. BIG is a randomised Phase 2 with 120 planned patients and an estimated primary completion in September 2027, according to ClinicalTrials.gov. The company's own dates disagree: the pipeline page gives an interim readout in 2026 and topline results in 2027, while its July 2026 update says the trial is "on track toward its primary endpoint readout in 2028". All the cancer trials are sponsored by hospitals or academic groups, which the company says "require minimal internal capital".

Exeliom's own accounts of how much it has raised do not add up the same way twice. In June 2023 it described a completed "€24 million" Series A made of €7 million in 2018, €3 million in 2021, €8 million in 2023 and "€6 million non-dilutive funding". In May 2024 it said a €1 million investment from the New York fund Forepont Capital Partners brought the Series A "to a total of €25 million", according to its post. In October 2025, announcing €2.85 million led by Biocodex, it said the extension brought "our Series A round to nearly €12M", according to its announcement; Vestbee and Life Sciences Europe reported €11.85 million, with the 2018 and 2021 money now labelled as seed funding. The equity amounts announced since 2018 add up to €21.85 million.

The Money

Exeliom files its accounts with a confidentiality declaration, so its balance sheet and staff costs are not public, as every BODACC accounts notice from 2018 to 2025 records. The only published figures are for 2023: no revenue and a net loss of €3,379,842, according to the INPI financial ratios dataset and the company search service. Non-dilutive money besides the EIC grant includes €1.8 million from Bpifrance's Deeptech programme in 2019, another €1.8 million from Bpifrance under the France 2030 recovery plan in 2024, and a $500,000 grant from the Crohn's & Colitis Foundation in 2024, all according to the company's newsroom; these amounts could not be confirmed in a second source.

Why Europe Should Care

Live biotherapeutics are a new class of medicine, and Exeliom's main technical result, making a strictly anaerobic gut bacterium to drug standards in Europe, is the kind of capability the EU's Pharmaceutical Strategy for Europe, adopted on 25 November 2020, says it wants: innovation for unmet medical needs, a competitive EU pharmaceutical industry and secure supply chains. The company's final report made the same case, saying an own manufacturing unit would "keep European know-hows on European ground". That larger manufacturing unit has not been announced.

The shift to oncology also fits EU priorities. Europe's Beating Cancer Plan, presented in February 2021, made cancer a central health policy. But the newest step is outside Europe: the first trial under a US FDA approval, with a US hospital, for which Exeliom said it would use part of its 2025 money to prepare "a new cancer indication in the US".

The Verdict

Exeliom Biosciences has not been asked for comment for this article. It is based entirely on public records, company statements, trial registries and EU project data, linked throughout.