Diagonal Therapeutics Secures $125M to Propel Innovative Antibody Therapies
January 11, 2026, 9:38 pm
Location: United States, California, Menlo Park
Employees: 51-200
Founded date: 2000
Diagonal Therapeutics secured $125M Series B funding. This advances DIAG723, a first-in-class clustering antibody. It targets hereditary hemorrhagic telangiectasia (HHT) and pulmonary arterial hypertension (PAH). The Watertown biotech corrects dysregulated signaling, offering disease-modifying therapy. Its DIAGONAL Product Engine drives innovative antibody discovery, expanding a pipeline for severe genetic diseases. Sanofi Ventures and Janus Henderson Investors co-led, boosting clinical progress.
Watertown, MA – Diagonal Therapeutics has made significant strides. The biotechnology company announced a major financial boost. It secured $125 million in an oversubscribed Series B financing round. This capital infusion accelerates its mission. It funds the advancement of its pioneering therapeutic pipeline. The company focuses on disease-modifying clustering antibodies. These address dysregulated signaling in severe genetic diseases.
Investor confidence is high. The Series B round saw robust participation. Sanofi Ventures and Janus Henderson Investors co-led the financing. Both played pivotal roles. New investors joined the effort. Deep Track Capital, EcoR1 Capital, and Logos Capital committed funds. Balyasny Asset Management and Woodline Partners also invested. Existing backers reaffirmed their support. Atlas Venture, BVF Partners, and Lightspeed Venture Partners participated. RA Capital Management, Frazier Life Sciences, and Viking Global Investors continued their involvement. RV Invest, Velosity Capital, Biovision Ventures, and Checkpoint Capital also contributed. This broad support underscores Diagonal’s potential.
Leadership expands with the new funding. Paulina Hill, Ph.D., now joins Diagonal’s Board of Directors. Dr. Hill is a Partner at Sanofi Ventures. Her expertise will guide strategic development. This appointment signifies a deeper collaboration. It strengthens governance and vision.
The funds primarily target DIAG723. This is Diagonal’s lead program. DIAG723 is a first-in-class clustering antibody. It represents a novel therapeutic approach. The antibody corrects underlying causes of disease. It specifically addresses hereditary hemorrhagic telangiectasia (HHT). It also targets pulmonary arterial hypertension (PAH). These are severe, often debilitating conditions.
DIAG723 works by restoring ALK1 signaling. This signaling pathway is crucial. It is impaired in endothelial cells for HHT and PAH patients. Genetic mutations disrupt receptor function. DIAG723 intervenes directly. It aims to restore normal cellular communication. This offers a disease-modifying strategy. It moves beyond symptomatic relief.
Preclinical data for DIAG723 are compelling. Studies show robust disease-modifying activity. The antibody prevents disease pathology. It also reverses existing pathology. This was observed across multiple preclinical models. It includes HHT and PAH models. Signalling was restored in cells derived from patient donors. These results build strong clinical anticipation.
The company plans to move DIAG723 into the clinic. A first-in-human study is slated for the first half of 2026. This initial trial will focus on HHT patients. The goal is to demonstrate safety and efficacy. It marks a critical milestone for the program.
HHT represents a significant unmet medical need. This rare genetic disorder affects over 330,000 individuals. Patients reside across the U.S. and EU. Currently, no approved therapies exist. The disease causes abnormal, fragile blood vessels. These are prone to rupture and bleeding. Complications are severe. They include chronic anemia, stroke, heart failure, and hemorrhage. DIAG723 offers a glimmer of hope. It could transform patient lives.
PAH is another devastating condition. This progressive disorder impacts approximately 200,000 patients globally. It is often fatal. Impaired signaling contributes to vascular hyperproliferation. This elevates pulmonary arterial pressure. Effective treatments are desperately needed. DIAG723 targets these fundamental dysfunctions.
DIAG723 has earned significant regulatory recognition. It received Orphan Drug Designation from the U.S. Food and Drug Administration (FDA). The European Medicines Agency (EMA) also granted this designation. Both recognitions are for the treatment of HHT. Orphan Drug status facilitates development. It offers incentives for therapies targeting rare diseases. This accelerates the path to patients.
Diagonal Therapeutics’ innovation stems from its platform. The DIAGONAL Product Engine is proprietary. It combines advanced computational methods. It integrates cutting-edge experimental techniques. This engine overcomes challenges inherent in antibody drug discovery. It streamlines the identification process. It efficiently delivers optimized therapeutic candidates. The platform is key to the company’s broad pipeline.
Beyond DIAG723, the pipeline is expanding. Diagonal is developing additional clustering antibodies. These target various therapeutic areas. Efforts span hematology, hepatology, and nephrology. The company aims to address a spectrum of severe genetic diseases. Each program seeks to correct underlying signaling defects. This commitment reflects a comprehensive approach to patient care.
Alex Lugovskoy, Ph.D., leads Diagonal Therapeutics. As Founder and CEO, he drives the company’s vision. His team possesses deep experience in drug development. They are dedicated to translating scientific breakthroughs into treatments. The company's focus remains on delivering life-changing therapies.
This $125 million Series B financing fuels Diagonal’s ambitions. It provides critical resources. It enables rapid clinical advancement. It supports platform innovation. The biotech community watches closely. Diagonal Therapeutics stands poised to redefine treatment paradigms. Its clustering antibodies hold profound promise for patients worldwide. The journey to delivering novel, disease-modifying therapies continues.
Watertown, MA – Diagonal Therapeutics has made significant strides. The biotechnology company announced a major financial boost. It secured $125 million in an oversubscribed Series B financing round. This capital infusion accelerates its mission. It funds the advancement of its pioneering therapeutic pipeline. The company focuses on disease-modifying clustering antibodies. These address dysregulated signaling in severe genetic diseases.
Investor confidence is high. The Series B round saw robust participation. Sanofi Ventures and Janus Henderson Investors co-led the financing. Both played pivotal roles. New investors joined the effort. Deep Track Capital, EcoR1 Capital, and Logos Capital committed funds. Balyasny Asset Management and Woodline Partners also invested. Existing backers reaffirmed their support. Atlas Venture, BVF Partners, and Lightspeed Venture Partners participated. RA Capital Management, Frazier Life Sciences, and Viking Global Investors continued their involvement. RV Invest, Velosity Capital, Biovision Ventures, and Checkpoint Capital also contributed. This broad support underscores Diagonal’s potential.
Leadership expands with the new funding. Paulina Hill, Ph.D., now joins Diagonal’s Board of Directors. Dr. Hill is a Partner at Sanofi Ventures. Her expertise will guide strategic development. This appointment signifies a deeper collaboration. It strengthens governance and vision.
The funds primarily target DIAG723. This is Diagonal’s lead program. DIAG723 is a first-in-class clustering antibody. It represents a novel therapeutic approach. The antibody corrects underlying causes of disease. It specifically addresses hereditary hemorrhagic telangiectasia (HHT). It also targets pulmonary arterial hypertension (PAH). These are severe, often debilitating conditions.
DIAG723 works by restoring ALK1 signaling. This signaling pathway is crucial. It is impaired in endothelial cells for HHT and PAH patients. Genetic mutations disrupt receptor function. DIAG723 intervenes directly. It aims to restore normal cellular communication. This offers a disease-modifying strategy. It moves beyond symptomatic relief.
Preclinical data for DIAG723 are compelling. Studies show robust disease-modifying activity. The antibody prevents disease pathology. It also reverses existing pathology. This was observed across multiple preclinical models. It includes HHT and PAH models. Signalling was restored in cells derived from patient donors. These results build strong clinical anticipation.
The company plans to move DIAG723 into the clinic. A first-in-human study is slated for the first half of 2026. This initial trial will focus on HHT patients. The goal is to demonstrate safety and efficacy. It marks a critical milestone for the program.
HHT represents a significant unmet medical need. This rare genetic disorder affects over 330,000 individuals. Patients reside across the U.S. and EU. Currently, no approved therapies exist. The disease causes abnormal, fragile blood vessels. These are prone to rupture and bleeding. Complications are severe. They include chronic anemia, stroke, heart failure, and hemorrhage. DIAG723 offers a glimmer of hope. It could transform patient lives.
PAH is another devastating condition. This progressive disorder impacts approximately 200,000 patients globally. It is often fatal. Impaired signaling contributes to vascular hyperproliferation. This elevates pulmonary arterial pressure. Effective treatments are desperately needed. DIAG723 targets these fundamental dysfunctions.
DIAG723 has earned significant regulatory recognition. It received Orphan Drug Designation from the U.S. Food and Drug Administration (FDA). The European Medicines Agency (EMA) also granted this designation. Both recognitions are for the treatment of HHT. Orphan Drug status facilitates development. It offers incentives for therapies targeting rare diseases. This accelerates the path to patients.
Diagonal Therapeutics’ innovation stems from its platform. The DIAGONAL Product Engine is proprietary. It combines advanced computational methods. It integrates cutting-edge experimental techniques. This engine overcomes challenges inherent in antibody drug discovery. It streamlines the identification process. It efficiently delivers optimized therapeutic candidates. The platform is key to the company’s broad pipeline.
Beyond DIAG723, the pipeline is expanding. Diagonal is developing additional clustering antibodies. These target various therapeutic areas. Efforts span hematology, hepatology, and nephrology. The company aims to address a spectrum of severe genetic diseases. Each program seeks to correct underlying signaling defects. This commitment reflects a comprehensive approach to patient care.
Alex Lugovskoy, Ph.D., leads Diagonal Therapeutics. As Founder and CEO, he drives the company’s vision. His team possesses deep experience in drug development. They are dedicated to translating scientific breakthroughs into treatments. The company's focus remains on delivering life-changing therapies.
This $125 million Series B financing fuels Diagonal’s ambitions. It provides critical resources. It enables rapid clinical advancement. It supports platform innovation. The biotech community watches closely. Diagonal Therapeutics stands poised to redefine treatment paradigms. Its clustering antibodies hold profound promise for patients worldwide. The journey to delivering novel, disease-modifying therapies continues.