SynOx Therapeutics announces $75m Series B round to fund Phase 3 trial of potential best-in-class treatment for TGCT

  • Financing co-led by Forbion, HealthCap and new investor Bioqube Ventures
  • Funds will be used for pivotal trial of potential best-in-class, next-generation treatment for Tenosynovial Giant Cell Tumour

 Dublin, Ireland and Oxford, UK, 22 April 2024: SynOx Therapeutics Limited (“SynOx” or the “Company”), the late-stage clinical biopharmaceutical company, is pleased to announce the close of a $75m Series B financing. The financing was co-led by Forbion, HealthCap and new investor Bioqube Ventures.

The proceeds will be used to generate registrational Phase 3 clinical and CMC data for emactuzumab, SynOx’s potentially best-in-class CSF-1(R) inhibiting monoclonal antibody (mAb) for the treatment of Tenosynovial Giant Cell Tumour (TGCT).

TGCT is a type of tumour that affects the soft tissue lining of joints and tendons and is a highly debilitating disease often impacting large, important joints such as the knee, hip and ankle.

TGCT is a chronic disease which often impacts patients throughout their lives.  It seriously impacts quality of life by causing significant loss of function of the affected joints, pain, stiffness, and limiting range of motion. While most patients receive surgical intervention, more than 50% of patients with diffuse disease experience tumour recurrence within three years of surgery1..

Emactuzumab is a novel, next-generation CSF-1R mAb with a potentially best-in-class profile.  In earlier clinical work in TGCT2. emactuzumab demonstrated substantial clinical activity with an objective response rate (ORR) of 71%, rapid and robust tumour reduction, a long duration of effect, and significant improvements in functional ability. Importantly, these studies also indicated that emactuzumab has good tolerability and a manageable safety profile. SynOx is initiating a Phase 3 trial (TANGENT) to assess the efficacy and safety of emactuzumab in patients with localized and diffuse TGCT.

As part of the Series B financing both Dr Carlo Incerti, M.D., and Jon Edwards, PhD, have joined the Board of Directors. Dr Incerti has more than three decades of experience in the biopharmaceutical industry and brings an extensive track record in global drug development, including from his time at Sanofi Genzyme where he played a leading role in pioneering therapies for rare and genetic diseases. Jon Edwards brings a decade of therapeutic investment expertise and company creation experience, which includes several public listings and multi-billion-dollar acquisitions.

Ray Barlow, Chief Executive Officer of SynOx Therapeutics, said: “This is a transformational time for SynOx. This substantial funding will allow us to generate registrational data for emactuzumab in TGCT. As a highly effective, next-generation therapy with a short treatment cycle, rapid onset and long duration of response, we believe that emactuzumab is differentiated from other agents in development and will provide a much needed and valuable option for patients suffering from this grievous disease.”

Dirk Kersten, General Partner at Forbion, commented: “We are pleased to continue to support the SynOx team as it moves emactuzumab through to BLA and MAA submissions in TGCT. As a late-stage company with a clinically de-risked asset, focused on an attractive and underserved market, SynOx is a good example of the type of company Forbion Growth would typically invest in.”

Jon Edwards, Bioqube Ventures commented: We are excited to join the SynOx syndicate and work with this fantastic team and board. We believe this asset has the potential to generate best-in-class data and are excited to help the team develop the product through approval and launch.

Ton Logtenberg, Non-Executive Chair of SynOx Therapeutics, added: “The support of our existing and new investors is validation of SynOx’s strategy and its great potential as a company. I would like to welcome Carlo Incerti and Jon Edwards to the Board of Directors. Their broad experience and knowledge, particularly in driving forward cutting-edge therapies for rare diseases, and executing deals at the highest level, complement the expertise of our existing directors and will be instrumental as we accelerate the late-stage clinical development of emactuzumab.”

For the full press release, please see SynOx Series B Press Release.


  1. Lin F, et. al. JHEOR, 2022.
  2. Cassier et al. “Long-term clinical activity, safety and patient-reported quality of life for emactuzumab-treated patients with diffuse-type tenosynovial giant-cell tumour” European Journal of Cancer 141:162-170, 2020