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The Effects of Cyproheptadine on Severe COVID-19 From the I-SPY COVID Adaptive Platform Trial
Sara C Auld1, Fady A Youssef1, Timothy E Albertson1
1Division of Pulmonary, Allergy, Critical Care and Sleep Medicine (S. C. A.), Department of Medicine, Emory University, Atlanta, GA; the Pulmonary Division (F. A. Y.), Department of Internal Medicine, Long Beach Memorial Medical Centre, Long Beach; the Division of Pulmonary, Critical Care and Sleep Medicine (T. A.), Department of Medicine, University of California, Davis, Sacramento; the Division of Pulmonary Diseases and Critical Care Medicine (R. A. L.), Department of Medicine, University of California, Irvine, Irvine; the Hoag Memorial Hospital Presbyterian Center for Research and Education (P. R.), Newport Beach; the Department of Pulmonary and Critical Care Medicine (K. K. W.), Kaiser Permanente Los Angeles Medical Center, Los Angeles; the Division of Pulmonary, Critical Care, Allergy and Sleep Medicine (C. S. C. and M. A. M.), Department of Medicine, the Divisions of Nephrology and Critical Care Medicine (K. D. L.), Department of Medicine, the Department of Surgery (L. J. E.), University of California, San Francisco, San Francisco, CA; the Centre for Acute Respiratory Failure (J. R. B.), Columbia University, New York; the Department of Pulmonary and Critical Care Medicine (C. Q.), University of Rochester, Rochester, NY; the Department of Critical Care (P. A. B.), Sanford Health, Sioux Falls, SD; the Department of Medicine (E. L. B.), University of Colorado, Denver, CO; the Department of Pulmonary and Critical Care (N. C.), Georgetown University Medical Centre, Washington, DC; the Department of Medicine (E. F.), Main Line Health, Wynnewood; the Department of Medicine (N. J. M.), University of Pennsylvania Perelman School of Medicine, Philadelphia, PA; the Department of Pulmonary, Allergy, and Critical Care Medicine (S. G. and D. W. R.), University of Alabama at Birmingham, Birmingham, AL; the Department of Pulmonary Critical Care, Allergy and Immunologic Disease (K. W. G.), the Department of Internal Medicine (D. C. F.), Wake Forest University, Winston-Salem, NC; the Department of Cardiovascular and Thoracic Surgery (J. H.), Heart and Vascular Institute, West Virginia University, Morgantown, WV; the Division of Pulmonary and Critical Care Medicine (R. H.), Department of Medicine, University of Michigan, Ann Arbor; the Department of Pulmonary and Critical Care (M. M. H. S. K.), Spectrum Health, Grand Rapids, MI; the Section of Pulmonary, Critical Care, and Sleep Medicine (J. L. K.), Department of Medicine, Yale University, New Haven, CT; the Department of Critical Care Medicine (T. O.), Logan Health Research Institute, Kalispell, MT; the Department of Critical Care Medicine (S. S.), Mercy Hospital, Springfield, MO; the Pulmonary and Critical Care Division (R. G. W.), Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL; and the Department of Medical Epidemiology and Biostatistics (M. E.), Karolinska Institutet, Stockholm, Sweden.
Background:
Severe COVID-19 has been associated with hypercoagulability and platelet activation, which is known to result in excessive accumulation of serotonin. However, few studies have evaluated whether serotonergic blockade may improve clinical outcomes among those with COVID-19.
Research Question:
Does cyproheptadine, an antiserotonergic drug most commonly used to treat serotonin syndrome, improve time to clinical recovery in patients with severe COVID-19?
Study Design And Methods:
The Investigation of Serial Studies to Predict Your Therapeutic Response With Imaging and Molecular Analysis in COVID (I-SPY COVID) study is a phase 2, multicenter, adaptive, open-label randomized controlled trial designed to screen potential therapeutic agents rapidly to identify those with a high probability of improving outcomes for hospitalized critically ill patients with COVID-19. For this report, participants randomized to receive cyproheptadine 8 mg enterally every 8 hours for 10 days or until hospital discharge were compared with concurrently enrolled control patients who were treated with the standard of care regimen of dexamethasone and remdesivir and did not receive an investigational agent. Bayesian survival regression models were used to model the hazard functions for the 2 events of interest: (1) recovery (treating death as a competing event) and (2) overall death as a function of randomization arm and baseline COVID-19 level.
Results:
From September through December 2021, 35 participants were randomized and consented to receive cyproheptadine and 61 concurrent control patients were eligible for analysis. At that point, futility criteria were met and the data monitoring committee halted further enrollment into the cyproheptadine arm. The posterior probability that cyproheptadine would increase the rate of recovery was 0.1% and the posterior probability that cyproheptadine would improve survival was 16.3%.
Interpretation:
In an open-label phase 2 trial of adults critically ill with severe COVID-19, cyproheptadine did not improve recovery or survival compared with the standard of care.
Clinical Trial Registration:
ClinicalTrials.gov; No.: NCT04488081; URL: www.clinicaltrials.gov.
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