Biotech veteran will lead clinical development of Diagonal’s clustering antibody pipeline, including DIAG723 for hereditary hemorrhagic telangiectasia (HHT) and pulmonary arterial hypertension (PAH)

WATERTOWN, Mass., July 08, 2025 (GLOBE NEWSWIRE) -- Diagonal Therapeutics, a biotechnology company focused on correcting dysregulated signaling with clustering antibodies that address the underlying cause of intractable genetic diseases, today announced the appointment of John Lee, M.D., Ph.D., as Chief Medical Officer. Dr. Lee brings over 25 years of combined experience in the pharmaceutical industry, academic medicine, and clinical practice, and has led worldwide drug development strategy and execution for numerous therapeutics.

Dr. Lee will oversee Diagonal’s clinical development programs, providing strategic direction and operational leadership as the company advances its pipeline into the clinic.

“We are thrilled to welcome John as our Chief Medical Officer,” said Alex Lugovskoy, Ph.D., Chief Executive Officer of Diagonal. “He brings a rare combination of clinical insight, scientific rigor, and compassionate leadership that will be incredibly impactful as we accelerate the development of DIAG723 for HHT and PAH. John’s extensive experience treating patients with these conditions will be valuable as we advance disease-modifying therapies that target the root cause of serious conditions, with the goal of transforming outcomes for individuals and families affected by these serious and underserved diseases.”

“Diagonal’s innovative receptor clustering approach unlocks new, high-impact opportunities to expand the utility of antibody drugs to directly address the underlying cause of historically challenging diseases,” said Dr. Lee. “The groundbreaking preclinical profile of DIAG723 in disease-relevant models of HHT and PAH, coupled with Diagonal’s bold vision and strong partnerships with the patient and physician communities, paves the way for a new generation of disease-modifying therapeutics to treat complex conditions. I look forward to collaborating with Diagonal's exceptional team to deliver meaningful medicines to patients who need them most.”

Dr. Lee is a physician-scientist who brings more than two decades of experience in the industry and as a practicing cardiologist. Before joining Diagonal, Dr. Lee served as Chief Medical Officer at Nuevocor, spearheading the development of a gene therapy program for genetic cardiomyopathies. Prior to Nuevocor, Dr. Lee served as Chief Medical Officer at PhaseBio Pharmaceuticals, where he led drug development across a broad pipeline of small-molecule and biologic candidates. Dr. Lee also held leadership roles at Quintiles Transnational Corp. as Vice President of Cardiovascular Innovation, Bristol-Myers Squibb as Executive Director and Therapeutic Area Head, and Merck & Co., where he began his career as Director of Global Medical Affairs. Dr. Lee previously practiced as a faculty cardiologist at the University of Pennsylvania Health System, completing his training in Internal Medicine and Cardiovascular Disease. He holds an M.D. and Ph.D. in Biochemistry from the Boston University School of Medicine and an undergraduate degree from Harvard University.

About Diagonal Therapeutics
Diagonal Therapeutics is a biotech company advancing novel disease-modifying clustering antibodies that repair dysregulated signaling implicated in a range of illnesses. The Company's DIAGONAL Product Engine combines proprietary computational and experimental techniques to overcome historical challenges associated with antibody drug discovery and efficiently deliver optimized therapeutic assets. Diagonal's pipeline comprises clustering antibodies designed to selectively address the underlying cause of disease across hematology, hepatology, and nephrology, offering the potential to deliver life-changing therapies for patients. For more information, please visit www.diagonaltx.com.

About DIAG723
‍DIAG723 is a bispecific antibody designed to address HHT and PAH, in which dysregulated ALK1 signaling in endothelial cells drives the formation of fragile arteriovenous malformations or vascular hyperproliferation, respectively. DIAG723 restores signaling lost due to mutations that impair receptor function. In multiple HHT preclinical studies, DIAG723 prevented and reversed arteriovenous malformations—a hallmark of HHT that can cause a host of bleeding-related complications in various organs. In addition, DIAG723 was found to restore signaling in multiple HHT patient donor samples. In preclinical models of PAH, DIAG723 prevented disease development, cardiac remodeling, and improved hemodynamics. DIAG723 also restored normal signaling in pulmonary microvascular endothelial cells derived from multiple PAH donors. DIAG723 has received orphan drug designation from the US FDA and the EMA for the treatment of HHT.

Media Contact
Marites Coulter
marites.coulter@deerfieldgroup.com