OMass Therapeutics Announces $310 Million Series C Financing to Advance Portfolio of Small Molecule Therapeutics in Endocrinology and Immunology

Financing co-led by new investors Bain Capital Life Sciences, Forbion and Novo Holdings, with strong participation from additional new and existing investors 

Proceeds to advance MC2 receptor antagonist OMS1620 through Phase 2 development and generate early clinical data for SLC15A4 inhibitor

Oxford, United Kingdom – 15 October 2026 – OMass Therapeutics (‘OMass’ or ‘the Company’), a biotechnology company developing small molecule therapeutics against highly validated target ecosystems, today announced an oversubscribed $310 million (£230 million) Series C financing round. Proceeds from the financing will support the advancement of the Company’s lead program, OMS1620, a potential best-in-class MC2 (melanocortin-2) receptor antagonist, through Phase 2 clinical development in congenital adrenal hyperplasia (CAH), as well as ACTH-dependent Cushing’s syndrome.

The round was co-led by new investors Bain Capital Life Sciences, Forbion and Novo Holdings, with additional participation from Janus Henderson Investors, SV Health Investors and Jefferson Life Sciences. Each of the Company’s existing investors also participated in the round, including Syncona, Oxford Science Enterprises, GV, Northpond Ventures, Sanofi Ventures, British Business Bank and University of Oxford.

OMS1620 has been designed to increase receptor residency time and maintain activity in the presence of rising endogenous ACTH levels. This can allow more patients with CAH to achieve androgen normalization while on physiologic doses of glucocorticoids.

The financing will also support OMass’ earlier-stage pipeline, including generation of initial clinical data for a potential first-in-class SLC15A4 inhibitor for lupus and other diseases associated with interferon overproduction and pathogenic B-cell activation.

“This financing comes at an exciting point in OMass’ evolution as we advance OMS1620 into the clinic, with our SLC15A4 inhibitor poised to follow,” said Ros Deegan, Chief Executive Officer of OMass Therapeutics. “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.”

In conjunction with the financing, Evan Greif of Bain Capital Life Sciences and Audrey Cacaly of Forbion will join the Company’s Board of Directors. Max Klement of Novo Holdings and Ali Jazayeri of SV Health Investors will receive Board observer seats.

“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,” said Evan Greif, Principal at Bain Capital Life Sciences. “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.”

“This financing has the potential to deliver clinical data for two differentiated programs, OMS1620 and SLC15A4, providing important opportunities to demonstrate their therapeutic potential,” said Audrey Cacaly, Principal at Forbion. “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.”

“We are pleased to join a premier investor syndicate supporting OMass as the Company advances its breakthrough programs into the clinic,” said Max Klement, Partner, Venture Investments at Novo Holdings. “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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About OMass Therapeutics

OMass Therapeutics is a biotechnology company developing small molecule therapeutics against highly validated target ecosystems. Its proprietary OdyssION™ drug discovery platform combines next-generation native mass spectrometry, novel biochemistry techniques and custom chemistry to interrogate drug targets within their native ecosystems, providing cell-system fidelity with cell-free precision.

OMass’ lead program, OMS1620, is a best-in-class MC2 (melanocortin-2) receptor antagonist for congenital adrenal hyperplasia (CAH) and ACTH-dependent Cushing’s syndrome, designed to maintain efficacy in the presence of elevated ACTH levels. OMass is also advancing a broader preclinical pipeline including an SLC15A4 inhibitor for lupus and other indications related to interferon overproduction and pathogenic B-cell activation.

Headquartered in Oxford, UK, OMass was founded as a spin-out from Professor Dame Carol Robinson’s lab at the University of Oxford to translate pioneering native mass spectrometry research into novel small molecule therapeutics against historically challenging targets. The Company is backed by a top-tier international investor syndicate.

To learn more, please visit www.omass.com. Follow us on LinkedIn.