Imbria Pharmaceuticals Secures $57.5 Million Series B to Advance Ninerafaxstat in Cardiovascular Disease Trials
Imbria Pharmaceuticals, a Boston-area clinical-stage biotechnology company focused on developing novel therapies for cardiometabolic and cardiovascular diseases, has successfully closed and expanded a major Series B financing round to support the continued clinical advancement of its lead therapeutic candidate, ninerafaxstat. The financing underscores strong investor confidence in the company’s scientific strategy and its potential to address significant unmet needs in cardiovascular medicine while progressing toward later-stage clinical milestones.
In April 2025, Imbria announced the closing of a $57.5 million Series B financing round led by new investor Deep Track Capital. This round brought together a top-tier syndicate of life science investors, combining fresh and existing backers to fuel the company’s mission of advancing ninerafaxstat through pivotal mid-stage clinical trials. Participation in the round included AN Ventures, Catalio Capital Management, Cytokinetics, Inc., RA Capital Management and SV Health Investors.
Imbria plans to use the proceeds from the Series B financing to support the ongoing global, multicenter FORTITUDE-HCM Phase 2b clinical trial of ninerafaxstat in non-obstructive hypertrophic cardiomyopathy (nHCM), a serious heart condition with no currently approved treatments. The Phase 2b study, initiated in mid-2025, is designed to evaluate the efficacy and safety of ninerafaxstat in improving disease symptoms and cardiac function, with topline data anticipated in late 2026. Beyond nHCM, the company has also explored ninerafaxstat’s potential in other cardiometabolic indications, including heart failure with preserved ejection fraction (HFpEF), with positive Phase 2a results previously reported.
Under the terms of the financing earlier in 2025, Imbria also made key leadership appointments, with Alvin Shih, MD stepping into the role of Chief Executive Officer. Dr. Shih, previously the company’s Executive Chair, brings extensive experience in biopharmaceutical leadership, having held senior roles across biotech organizations with expertise in clinical development and corporate strategy. Additionally, Rebecca Luse, Managing Director at Deep Track Capital, was appointed to the company’s Board of Directors, strengthening investor involvement at the governance level.
Later in November 2025, Imbria announced an extension of its Series B financing, bringing in AXA IM Alts as a new investor committed to expanding the depth and global reach of support for the company’s cardiovascular therapeutic development. The extended round reaffirmed commitment from the existing investor group, including Deep Track Capital, AN Ventures, Catalio Capital Management, RA Capital Management, SV Health Investors and Cytokinetics, Inc. As part of this expanded financing, Dr. Zina Affas Besse, Partner and Deputy Head of Healthcare Private Equity at AXA IM Alts, joined Imbria’s Board of Directors, contributing decades of healthcare investment expertise. Ken Horne, Managing Partner at AN Ventures, was also appointed to the board, enhancing strategic leadership as Imbria advances its clinical programs.
The addition of AXA IM Alts to the investor syndicate highlights growing interest from global healthcare investors in Imbria’s approach to treating cardiovascular diseases by targeting cellular energy metabolism. Ninerafaxstat, the company’s lead compound, is designed to improve cardiac energetics by shifting substrate utilization in the heart’s mitochondria—an innovative mechanism that could offer benefits in multiple cardiometabolic disorders.
Imbria’s Series B financing success comes at a time when the biotech industry continues to prioritize breakthroughs in heart disease therapeutics, with cardiovascular disease remaining a leading cause of death worldwide. The extended capital raise and strategic investor expansions position Imbria to sustain its clinical momentum, scale operational capabilities and pursue data generation that may support eventual regulatory submissions.
By assembling a syndicate of specialized life science investors and expanding its board with seasoned healthcare capital leaders, Imbria Pharmaceuticals is strengthening its bridge from mid-stage clinical development toward potential late-stage programs and broader therapeutic impact. The funding efforts illustrate both investor confidence in ninerafaxstat’s clinical promise and the company’s strategic positioning within the competitive landscape of cardiovascular drug development.
