Star Therapeutics announced an oversubscribed $125 million Series D financing round to support the continued clinical advancement of VGA039, its first-in-class monoclonal antibody targeting Protein S for bleeding disorders. The financing was co-led by Sanofi Ventures and Viking Global Investors, with participation from new investors including Janus Henderson Investors, Frazier Life Sciences, and GordonMD Global Investments.
The proceeds will primarily fund the advancement of VGA039, which has recently initiated a pivotal Phase 3 clinical trial in patients with von Willebrand disease (VWD). VGA039 represents a novel approach to treating bleeding disorders by targeting Protein S to restore balance in blood clotting processes.
Novel Therapeutic Approach for Bleeding Disorders
VGA039 is being developed as a universal hemostatic therapy with the potential to treat multiple bleeding disorders, starting with VWD. The monoclonal antibody therapy offers a subcutaneous, once-monthly dosing regimen that could dramatically reduce treatment burden for patients compared to current standard of care.
"VGA039 has the potential to be transformative for VWD patients and could meaningfully reduce the treatment burden, given its once monthly subcutaneous dosing regimen, in comparison to factor replacement prophylaxis which requires two to three IV infusions per week," said Adam Rosenthal, Ph.D., CEO and Founder of Star Therapeutics.
The therapy has received Fast Track and orphan drug designations from the FDA, highlighting its potential to address significant unmet medical needs in the bleeding disorder space.
Addressing the Most Common Inherited Bleeding Disorder
Von Willebrand disease is the most common inherited bleeding disorder, caused by absent or defective von Willebrand factor (VWF). The condition affects blood clotting ability, leading to excessive bleeding that can vary in severity and frequency, negatively impacting patients' daily lives.
More than 50,000 people in the United States are estimated to be receiving treatment for VWD. Current therapies for VWD prophylaxis include factor replacement therapies requiring multiple intravenous infusions every week, creating a significant treatment burden for patients.
VGA039 is designed to address all types of VWD and all types of bleeds, positioning it as the first subcutaneous therapy with once-monthly dosing for this patient population.
Clinical Development Progress
The company has initiated VIVID-6 (NCT07115004), a global single-arm crossover Phase 3 study designed to investigate the safety and efficacy of subcutaneous VGA039 administration as prophylaxis for bleeding in patients with every type of VWD.
Previous clinical data supporting the Phase 3 advancement includes interim positive results from VIVID-2, a Phase 1 single ascending dose study of VGA039 in VWD patients, which were reported at the Annual Meeting of the American Society of Hematology in December 2024. Additionally, a Phase 1/2 multidose study, VIVID-3, is currently ongoing (NCT05776069).
Strategic Investment and Leadership
The financing round included participation from both new and existing investors. Existing investors include Agent Capital, Blue Owl Capital, Catalio Capital Management, Cormorant Asset Management, New Leaf Venture Partners, NYBC Ventures, OrbiMed, Qatar Investment Authority (QIA), RA Capital Management, Redmile Group, Sofinnova Investments, Soleus Capital, and Westlake BioPartners.
In conjunction with the financing, Jason Hafler, Ph.D., from Sanofi Ventures will join Star's board of directors, and Maneka Mirchandaney of Viking Global Investors will join as a board observer.
"VWD represents a compelling opportunity, with a sizable patient population and significant unmet need," said Jason Hafler, Ph.D., Managing Director at Sanofi Ventures. "With VGA039 advancing into Phase 3 for VWD, Star is well-positioned to deliver both substantial patient impact and long-term value."
Company Background and Pipeline
Star Therapeutics is a clinical-stage biotechnology company focused on discovering and developing best-in-class antibodies for bleeding disorders and other diseases in hematology and immunology. The company's leadership team has deep expertise in novel antibody drug development, having invented four first-in-class antibodies including the first approved drug (ENJAYMO®) for cold agglutinin disease.
With this Series D financing, Star has raised more than $300 million from leading life sciences investors. The company applies its expertise in antibody innovation to interrogate areas of biology that have been overlooked and have the potential to address multiple diseases with a single therapy.
