OMass Therapeutics closes £233.8m series C led by Bain Capital Life Sciences and Forbion
This article covers OMass Therapeutics, an Oxford-based biotech startup, which has closed a series C funding round of £233.8m to advance its lead small-molecule candidate OMS1620 into Phase 2 and to generate early human data for an SLC15A4 inhibitor targeting autoimmune disease. The financing will fund late-stage clinical work and early clinical data generation for programmes in endocrinology and immunology, supporting development of treatments for these conditions and reflecting substantial international investor participation in UK biotech.
Oxford-based biotech startup OMass Therapeutics has closed a series C funding round of £233.8m to push its lead small-molecule candidate, OMS1620, into Phase 2 and to generate early human data for an SLC15A4 inhibitor targeting autoimmune disease. The size and syndicate behind the round matter because they signal continued heavyweight capital flowing into UK biotech programmes that are moving from discovery into clinical proof of concept.
Why it matters
The financing will underwrite late-stage clinical work on a candidate aimed at congenital adrenal hyperplasia (CAH) and ACTH-dependent Cushing’s syndrome, conditions with limited targeted treatment options. Achieving clinical proof for two differentiated programmes from internal discovery would strengthen the case for UK-origin small-molecule drug discovery and could attract more international life sciences capital into the Oxford cluster.
The deal also highlights a broader trend: larger international funds are participating directly in UK biotech financings rather than only following in later rounds. That influences how startups plan development timelines and board composition as they scale clinical programmes.
Inside the product
OMS1620 is described by the company as a potential best-in-class antagonist of the MC2 (melanocortin-2) receptor. OMass says the molecule is designed to increase receptor residency time and retain activity when endogenous ACTH rises, which the company expects could let more patients with CAH achieve androgen normalisation on physiologic doses of glucocorticoids.
The earlier-stage programme targets SLC15A4, a transporter implicated in interferon overproduction and pathogenic B-cell activation, and is being advanced toward initial clinical data for lupus and related indications.
OMass’s discovery engine, called OdyssION, combines native mass spectrometry with bespoke biochemistry and chemistry to interrogate targets in their native molecular ecosystems. The company was spun out of Professor Dame Carol Robinson’s lab at the University of Oxford and emphasises in-house discovery rather than external licensing for its pipeline.
Who are the investors?
The round was co-led by Bain Capital Life Sciences, Forbion and Novo Holdings, with participation from Janus Henderson Investors, SV Health Investors and Jefferson Life Sciences. Existing backers that participated included Syncona, Oxford Science Enterprises, GV, Northpond Ventures, Sanofi Ventures, British Business Bank and the University of Oxford.
Bain Capital Life Sciences, Forbion and Novo Holdings are established life sciences investors with international portfolios; their co-lead roles bring both capital and governance influence. Syncona and Oxford Science Enterprises are well-known UK investors that often back translational science and university spinouts. GV and Northpond Ventures add US-based venture capital weight, while Sanofi Ventures represents corporate strategic interest.
In conjunction with the financing, Evan Greif of Bain Capital Life Sciences and Audrey Cacaly of Forbion will join the OMass board; Max Klement of Novo Holdings and Ali Jazayeri of SV Health Investors will join as board observers.
In the announcement, Evan Greif, Principal at Bain Capital Life Sciences, said:
OMass leverages an experienced team and a clear vision for building a leading therapeutics company that translates complex biology into differentiated medicines for patients with significant unmet needs. The Company is executing against that vision by advancing OMS1620 and applying its proprietary discovery approach to build a broader pipeline across endocrinology and immunology. We see meaningful potential for OMS1620 to improve the treatment for patients with CAH and look forward to partnering with Ros and the team to support the Company’s strategic and patient-first approach.
In the announcement, Audrey Cacaly, Principal at Forbion, said:
This financing has the potential to deliver clinical data for two differentiated programs, OMS1620 and SLC15A4, providing important opportunities to demonstrate their therapeutic potential. These programs are part of a pipeline built entirely through internal discovery, underscoring the productivity and breadth of OMass’ platform and its potential to generate meaningful new medicines across endocrine and immunologic diseases. We look forward to working closely with the talented OMass team as they advance these programs.
In the announcement, Max Klement, Partner, Venture Investments at Novo Holdings, said:
We are pleased to join a premier investor syndicate supporting OMass as the Company advances its breakthrough programs into the clinic. Each of these candidates has the potential to address substantial unmet patient needs in their respective areas of endocrinology and immunology, and we look forward to the Company’s continuing progress.
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Founder perspective
In the announcement, Ros Deegan, Chief Executive Officer of OMass Therapeutics, said:
This financing comes at an exciting point in OMass’ evolution as we advance OMS1620 into the clinic, with our SLC15A4 inhibitor poised to follow. We have demonstrated the ability of our team and approach to discover and deliver a pipeline of first- and best-in-class programs in endocrinology and immunology into the clinic. With the backing of an outstanding group of new and existing investors, we are entering our next phase of growth with the resources to translate that progress into a portfolio of clinically differentiated medicines for patients.
Deegan’s comment frames the round as both confirmation of the platform’s productivity and a resource step-change for derisking clinical hypotheses.
The bigger picture
This financing underscores continued appetite among biotech investors for UK-founded discovery platforms that can generate small-molecule candidates against challenging targets. It also reflects a pattern where large crossover and specialist life sciences funds are willing to lead sizable Series C rounds for companies demonstrating clear translational progress.
For the Oxford ecosystem, the deal is another example of university-linked spinouts progressing to later-stage financings while retaining strong academic ties. If OMS1620 and the SLC15A4 programme deliver positive data, it could reinforce investor confidence in platform-driven small-molecule discovery and encourage further capital flows into UK and European biotech.
They've invested in OMass Therapeutics
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