TRexBio Closes the Final Tranche of $59 Million Series A Financing to Advance Innovation in Tissue Immunobiology for the treatment of Cancer and Inflammatory Diseases

in Portfolio News

  • Industry veteran Johnston Erwin appointed as Chief Executive Officer
  • Ovid Trifan, M.D., Ph.D., appointed as Chief Medical Officer

June 22, 2021 08:00 AM Eastern Daylight Time

SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)--TRexBio, a discovery stage company decoding human tissue immune biology to create revolutionary therapeutics, announced the successful close of the final tranche of a $59 million Series A financing. Proceeds from the financing will be used to expand the company’s unique discovery platform that maps human tissue regulatory T cell (Treg) behavior to dysregulation in disease, and to advance its six preclinical therapeutic programs. Investors include Eli Lilly and Company (Lilly), SV Health, Johnson & Johnson Innovation, Pfizer Ventures, and Alexandria Venture Investments.

“The continued support from our investors further validates our approach to creating breakthrough therapeutics,” said Carol Gallagher, Pharm.D., Executive Chair of TRexBio, and former President and CEO of Calistoga Pharmaceuticals. “We look forward to working with our investors and our academic and industry collaborators as we continue to create and advance a robust pipeline that addresses serious illnesses including cancer and auto-immune diseases.”

TRexBio also announced the appointment of Johnston Erwin as Chief Executive Officer, and Ovid Trifan, M.D., Ph.D., as Chief Medical Officer, as part of the company’s plan to accelerate growth. Johnston, a seasoned industry veteran with experience in business development, venture investment, collaboration management, and clinical and regulatory development, joins TRexBio after a 36 year career with Lilly. He most recently served as VP of Corporate Business Development leading Lilly’s internal venture portfolio.

“TRex is at the forefront of one of the most exciting new areas in immunobiology and tissue homeostasis,” said Johnston. “The company has a significant foundation in place, with a compelling vision, dedicated team and robust science. I am excited to lead the company into its next stage of development and ultimately transform the lives of patients by bringing a new generation of immune-based therapies to the world.”

Dr. Trifan brings more than 20 years of medical research experience to TRexBio. Most recently he was the Chief Medical Officer and VP of Development at Apexigen, a clinical stage biotech company focused on immuno-oncology. Prior to Apexigen he held senior roles in clinical research at leading pharmaceutical companies including Bristol Myers Squibb and Johnson & Johnson, where he contributed to the development of multiple successful oncology drugs. Dr. Trifan will lead the advancement of TRexBio’s oncology programs into the clinic by the end of next year.

Mr. Erwin and Dr. Trifan are joined on the management team by Chief Scientific Officer Melanie Kleinschek, DVM, Ph.D., who has led the development of TRexBio’s unique ‘deep biology’ discovery platform. The platform uses high-resolution profiling of human tissue, modern computational biology tools, a proprietary system to generate tissue-like Tregs and disease-relevant phenotypic assays to generate novel insights into human tissue biology.

TRexBio’s accomplishments to date include:

  • Foundational collaborations with Lilly and the University of California San Francisco.
  • Advancement of six preclinical therapeutic programs across immuno-oncology and inflammation, two of which are on track to name development candidates in the next 12 months.
  • Identification of more than 20 novel tissue-focused targets from its proprietary ‘deep biology’ platform

The company works with an internationally recognized team of founding scientific advisors, including

  • Michael D. Rosenblum, M.D., Ph.D., Professor of Dermatology, Vice Chair of Research UCSF, and Co-Founder of Delinia Therapeutics;
  • Houman Ashrafian, BM Bch, DPhil, Managing Partner at SV Health Investors and former VP, Head of Clinical Science at UCB;
  • Adil Daud, M.D., Professor, Department of Medicine, Hematology/Oncology Director Melanoma Clinical Research, UCSF;
  • Diane Mathis, Ph.D., Professor in the Department of Immunology at Harvard Medical School, and holder of the Morton Grove-Rasmussen Chair in Immunohematology; and
  • Allison Simmons, M.D., Ph.D., Professor of Gastroenterology and Director of the MRC Human Immunology Unit at the University of Oxford.

About TRexBio

TRexBio is a discovery stage biotechnology company leveraging cutting edge computational biology tools, a focus on human tissue, and expertise in immunobiology to develop revolutionary therapeutics for cancer and inflammatory diseases. Our powerful ‘deep biology’ discovery engine maps human tissue Treg behavior to disease processes, allowing us to identify and characterize novel targets for therapeutic intervention. Leveraging this platform, we are building a broad portfolio of novel therapies that modulate the immune system to restore human tissue immune homeostasis. TRexBio is headquartered in South San Francisco, California. For more information, please visit or follow us on LinkedIn.


Heidi Chokeir, Ph.D.
Canale Communications

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