Microbiotica has closed the first tranche of a £36 million ($48 million) Series C round, announced 16 October 2026 and led by the British Business Bank, the UK government’s economic-development lender. The Cambridge, England biotech will use the money to push MB310, an oral capsule of eight live gut bacteria, into a randomised Phase 2 trial for ulcerative colitis — the next step after a Phase 1b readout that beat placebo on clinical remission.
Ten years from a Sanger Institute spin-out
Microbiotica was spun out of the Wellcome Sanger Institute in December 2016 by Mike Romanos, Trevor Lawley and Gordon Dougan, with an £8 million seed round from Cambridge Innovation Capital and IP Group. The company’s pitch from the start was that most microbiome medicine had been guesswork — dosing whole donor stool samples or broad bacterial blends and hoping for a response — and that Sanger’s genomic sequencing capability could instead identify which specific gut bacteria track with disease and treatment response, strain by strain.
Microbiotica’s ten years, mapped
- December 2016
Microbiotica founded
Spun out of the Wellcome Sanger Institute by Mike Romanos, Trevor Lawley and Gordon Dougan, with an £8 million seed round from Cambridge Innovation Capital and IP Group.
- March 2022
£50M Series B
Co-led by Tencent and Flerie Invest; described at the time as the largest microbiome-focused financing in Europe, funding Phase 1b trials of MB097 and MB310.
- November 2022
Leadership change
Co-founder and CEO Mike Romanos stepped down after six years; chief operating officer Tim Sharpington became CEO.
- November 2024
First COMPOSER-1 patient dosed
First patient dosed in the Phase 1b trial of MB310 in ulcerative colitis.
- August 2025
COMPOSER-1 recruitment complete
29 adult patients enrolled across clinical centres in the UK, Austria, Bulgaria, Poland and Spain.
- 16 October 2026
£36M Series C, first close
Led by the British Business Bank, to fund MB310’s move into a randomised Phase 2 trial.
- Ahead
Phase 2 and a further close
Microbiotica has said it will explore further partnering and financing options alongside the Phase 2 trial.
MB310’s Series C in four numbers
Trial figures from Microbiotica’s COMPOSER-1 disclosures; financing figures from the 16 October 2026 announcement.
Eight strains in one daily capsule
MB310 is an oral capsule, taken once daily, containing a defined consortium of eight live gut commensal bacterial strains. Microbiotica says the strains were identified through genomic analysis of gut-bacteria data, including work with the University of Adelaide, rather than assembled from a broad donor stool sample as earlier fecal-transplant approaches to the gut microbiome have been. Preclinical work points to three mechanisms: repairing the gut’s epithelial barrier, rebalancing inflammatory and immune-modulatory cytokines, and inducing a regulatory T-cell response.
“This financing marks an important next stage for Microbiotica and reflects the significant progress we have made in translating our powerful genomics-driven microbiome platform into clinical-stage products…” Tim Sharpington, Chief Executive Officer, Microbiotica — 16 October 2026 announcement
What eight strains are supposed to do
Rational strain selection
Unlike broad-spectrum fecal transplants, MB310’s eight strains were selected from Microbiotica’s own genomic analysis of gut bacteria linked to disease and treatment response, rather than transplanting an entire donor microbiome.
Beat placebo in Phase 1b
In the COMPOSER-1 trial, MB310 achieved clinical remission in 12 of 19 treated patients (63%) against 3 of 10 (30%) on placebo, on an intent-to-treat basis, with a safety profile the company describes as indistinguishable from placebo.
Backed by a state development bank
The British Business Bank, the UK government’s economic-development lender, led this round — a vote of confidence from a public institution that smaller private funds alone might not provide.
The biologics aisle MB310 would enter
Ulcerative colitis is already treated with injected or infused biologics and oral JAK inhibitors, and a meaningful share of patients either fail to respond to those drugs or lose response over time. Microbiotica is not positioning MB310 to compete head-on with that category on potency; the company’s pitch is a differently mechanized, oral, bacteria-based option for the patients those drugs do not adequately serve, developed from its own platform rather than a licensed-in molecule.
The disease MB310 is chasing, priced two ways
$10.8B → $13.6B
Global ulcerative colitis treatment market, 2025 to 2031, as forecast by Mordor Intelligence (2026) and Allied Market Research (2022, for 2030).
Sources: Mordor Intelligence, US Ulcerative Colitis Market Analysis, 2026 · Allied Market Research, Global Ulcerative Colitis Market (via GlobeNewswire), 2022
Regulatory News outlook
We expect microbiome-based therapies like MB310 to remain a small slice of a market still dominated by biologics and JAK inhibitors through the early 2030s, but one of the few approaches aimed at patients who fail or can’t tolerate those drugs rather than competing head-on with them.
How we got here: Mordor Intelligence’s $10.56 billion 2025 estimate for the global ulcerative colitis market, compounded at its own reported 4.31% annual growth rate, reaches about $13.6 billion by 2031 — in line with its own published figure; we treat Allied Market Research’s separate $10.8 billion 2030 estimate as a floor given its older, lower base-year figure.
MB310 against ulcerative colitis’s standard drugs
| Product | Type | Mechanism | Stage | Trial evidence so far |
|---|---|---|---|---|
| MB310 (Microbiotica) | Oral live biotherapeutic (8 bacterial strains) | Rebalances the gut microbiome | Phase 1b complete; Phase 2 planned | 63% clinical remission vs. 30% on placebo in COMPOSER-1 (n=29) |
| Biologics (anti-TNF and anti-integrin class) | Injected or infused monoclonal antibody | Blocks TNF-alpha or gut-specific integrins | Approved; multiple drugs on market | Established efficacy; a meaningful share of patients lose response over time |
| JAK inhibitors (oral small-molecule class) | Oral small molecule | Blocks JAK signalling pathways broadly | Approved; multiple drugs on market | Effective for some biologic-refractory patients; carry boxed safety warnings |
From Microbiotica’s own trial disclosures and each drug class’s general mechanism of action; not a head-to-head clinical comparison.
The second close Microbiotica still needs
A “first close” is a specific signal: Microbiotica is telling the market it has enough committed capital to start Phase 2 but is still raising rather than fully funded. The company has said it will explore further partnering and financing options during 2026, which leaves open whether the Series C grows further, a partner buys into MB310 directly, or both. Its other lead programme, MB097, developed for immuno-oncology alongside KEYTRUDA, remains in earlier-stage testing and was not part of this announcement.
- Phase 2 trial: a randomised, placebo-controlled study of MB310 in ulcerative colitis, funded by this round’s first close.
- Second close: Microbiotica has said it will explore further partnering and financing options during 2026; the current close is explicitly a first tranche, not the full round.
- MB097: the company’s other lead live biotherapeutic, developed for immuno-oncology alongside KEYTRUDA, remains in earlier-stage testing.
Sources & further reading
- BioIndustry Association, “Microbiotica raises £36 million ($48 million) in Series C financing to advance pipeline into Phase 2 clinical development,” 16 October 2026. bioindustry.org
- Cambridge Innovation Capital, “Microbiotica raises £36 million ($48 million) in Series C financing…,” 16 October 2026. cic.vc
- IP Group plc, RNS announcement, “Microbiotica raises £36m in Series C financing,” 16 October 2026. investegate.co.uk
- Proactive Investors, “Microbiotica CEO on £36m raise to advance gut treatment into Phase 2; IP Group invests £4m,” 16 October 2026. proactiveinvestors.com
- BusinessCloud, “Microbiotica raises £36m for cutting-edge IBD treatment,” 16 October 2026. businesscloud.co.uk
- ClinicalTrials.gov, COMPOSER-1 (NCT06582264): A Phase 1b Trial to Evaluate the Safety of MB310 in Patients With Active, Mild-to-Moderate Ulcerative Colitis. clinicaltrials.gov
- Cambridge Network, “CIC and IP Group announce creation of Sanger Institute spinout with £8m funding,” December 2016. cambridgenetwork.co.uk
- BioSpace, “Microbiotica Raises £50m ($67m) to Advance Pipeline of Microbiome-based Therapeutics,” March 2022. biospace.com
- BusinessWire, “Microbiotica Announces Transition of Leadership,” 29 November 2022. businesswire.com
- Mordor Intelligence, US Ulcerative Colitis Market Analysis, 2026. insights10.com
- BioSpace, “Ulcerative Colitis Market Size to Hit Around $10.8 Billion by 2030,” citing Allied Market Research, 2022. biospace.com
Regulatory News reports on public regulatory documents. It is not legal advice, and the primary sources above govern. If we have made an error, we will say so in public: see corrections.
Frequently asked questions
How much did Microbiotica raise?
A first close of £36 million ($48 million) toward a Series C round, announced 16 October 2026 and led by the British Business Bank, with Tencent, IP Group, Cambridge Innovation Capital, Flerie Invest and Seventure Partners also participating. The company has said it will pursue a further close as it explores additional partnering and financing options.
What is MB310?
An oral, once-daily capsule containing a defined consortium of eight live gut commensal bacterial strains, developed by Microbiotica from its own genomic analysis of the human gut microbiome, for patients with ulcerative colitis.
What did Microbiotica's Phase 1b trial show?
In the COMPOSER-1 trial (NCT06582264), 12 of 19 patients treated with MB310 (63%) reached clinical remission, against 3 of 10 (30%) on placebo, on an intent-to-treat basis, with a safety profile the company describes as indistinguishable from placebo.
Is Microbiotica a public company?
No. Microbiotica is privately held, based at Chesterford Research Park near Cambridge, England. It has no listed shares; the British Business Bank is a UK government-owned development lender, not a stock exchange or regulator.
