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Cardurion Pharmaceuticals Announces Dosing of Patients in CARDINAL-HF, a Phase 2 Clinical Trial of its PDE9 inhibitor in Heart Failure

  • CARDINAL-HF is the first Phase 2 proof-of-concept trial of a PDE9 inhibitor in heart failure
  • Large-scale trial builds upon encouraging data generated in Cardurion’s Phase 1b trial
  • CARDINAL-HF will examine the effects of CRD-740, Cardurion’s PDE9 inhibitor, in both types of heart failure and in key subsets of these patients


BOSTON – July 19, 2022 – Cardurion Pharmaceuticals, Inc. (“Cardurion” or “the Company”), a clinical-stage biotechnology company developing next-generation therapeutics for the treatment of cardiovascular diseases, today announced it has opened multiple sites and commenced dosing patients in a Phase 2 clinical trial of CRD-740, a phosphodiesterase-9 (“PDE9”) inhibitor for the treatment of heart failure. Initiated in May 2022, CARDINAL-HF is the first Phase 2 proof-of-concept trial of a PDE9 inhibitor in heart failure, and will assess the effects of CRD-740 on key subsets of these patients. Based on the mechanism of PDE9 action, inhibition by CRD-740 is expected to have benefit both alone and in combination with all standard of care heart failure treatments.

CARDINAL-HF is a randomized, placebo-controlled trial that will enroll over 650 patients at more than 100 trial sites around the world. The trial will include chronic, stable patients with both reduced (HFrEF) and preserved ejection fraction heart failure (HFpEF). In addition, CRD-740 is being tested on a background of standard of care therapies to provide important information on the potential for benefit of CRD-740 when combined with guideline-directed treatments.

The target of CRD-740 is PDE9, the enzyme that metabolizes cardiac cGMP generated by the natriuretic peptide receptor (NPR) pathway. Activation of this pathway is of proven clinical benefit in both forms of heart failure. PDE9 activity is increased in heart failure patients, which limits the beneficial effects of the NPR pathway. PDE9 inhibition with CRD-740 is a novel approach capable of maximizing NPR pathway activation and the beneficial effects of cGMP generated by this pathway, by blocking its breakdown by the PDE9 enzyme.

“The launch of this large-scale trial is a significant milestone for Cardurion and for millions of patients who suffer from heart failure and are underserved by currently available therapies. We are gratified to have assembled a world-class group of cardiovascular experts to help oversee its execution,” said Peter Lawrence, Chief Executive Officer of Cardurion Pharmaceuticals. “We believe that CARDINAL-HF will rigorously test CRD-740 in both HFrEF and HFpEF, allowing us to assess the value of PDE9 inhibition in these patient populations, including important subgroups of patients who are on other heart failure medications. The data from this trial will be extensive and allow for robust decision-making for Phase 3.”

The Executive Committee for the trial includes Dr. James Udelson, Principal Investigator and Chief of Cardiology at Tufts Medical Center; Dr. Scott Solomon, Professor of Medicine at Harvard Medical School; and Dr. John McMurray, Professor of Medical Cardiology and Deputy Director of the Institute of Cardiovascular and Medical Sciences at the University of Glasgow. Drs. Udelson, Solomon and McMurray, along with Dr. Eugene Braunwald, the Distinguished Hersey Professor of Medicine at Harvard Medical School, also lead Cardurion’s Clinical Advisory Board. The CARDINAL-HF Steering Committee is further comprised of leading international heart failure trialists.

“CARDINAL-HF has been carefully designed to evaluate how a broad range of heart failure patients will respond to this novel drug candidate, which has the potential to address significant unmet medical need when added to the current standard of care,” said Dr. Jim Udelson, Principal Investigator for the CARDINAL-HF trial. “The design will also provide a rich data set to inform the structure of a Phase 3 program and help evaluate a potential patient selection biomarker.”

About Cardurion Pharmaceuticals

Heart failure is a prevalent and growing condition that is responsible for substantial morbidity and mortality. Approximately 6.5 million people in the U.S. suffer from heart failure, and 50 percent of these patients die from the condition within five years of diagnosis. One in five patients are hospitalized annually, and 25% of hospitalized heart failure patients will be admitted again within a month of discharge. Approximately half of heart failure patients have reduced ejection fraction and half have preserved ejection fraction. Despite the availability of drugs indicated to reduce morbidity and mortality in both types of heart failure, substantial unmet medical need remains.


About Cardurion Pharmaceuticals

Cardurion Pharmaceuticals is a clinical-stage biotechnology company focused on the discovery and development of novel, next-generation therapeutics for the treatment of heart failure and other cardiovascular diseases. Founded by physician-scientist Michael E. Mendelsohn, M.D., and built by a team of physician-scientists and industry leaders with extensive experience in cardiovascular science, drug development and business development, Cardurion Pharmaceuticals is pursuing unique drug discovery and development programs to target major unmet needs in cardiovascular medicine. Cardurion Pharmaceuticals has facilities in Boston and Burlington, Massachusetts and Shonan, Japan. For more information, please visit the company’s website at

Media Contact:

Scott Lessne



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