Sean Hennessy, PharmD, PhD
Professor of Epidemiology in Biostatistics and Epidemiology
Senior Fellow, Leonard Davis Institute of Health Economics, University of Pennsylvania
Fellow, Institute on Aging, University of Pennsylvania
Senior Scholar, Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania Perelman School of Medicine
Founding Director, Center for Real-World Effectiveness and Safety of Therapeutics, University of Pennsylvania Perelman School of Medicine
Member, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine
Department: Biostatistics and Epidemiology
Contact information
University of Pennsylvania
3600 Civic Center Boulevard
4W-105C
Philadelphia, PA 19104-3413
3600 Civic Center Boulevard
4W-105C
Philadelphia, PA 19104-3413
Office: 215-898-9112
Email:
hennessy@upenn.edu
hennessy@upenn.edu
Graduate Group Affiliations
Publications
Education
BS (Pharmacy)
Philadelphia College of Pharmacy and Science, 1989.
PharmD (Clinical Pharmacy)
Philadelphia College of Pharmacy and Science, 1990.
MSCE (Clinical Epidemiology)
University of Pennsylvania School of Medicine, 1996.
PhD (Epidemiology with Biostatistics minor)
University of Pennsylvania, 2002.
BS (Pharmacy)
Philadelphia College of Pharmacy and Science, 1989.
PharmD (Clinical Pharmacy)
Philadelphia College of Pharmacy and Science, 1990.
MSCE (Clinical Epidemiology)
University of Pennsylvania School of Medicine, 1996.
PhD (Epidemiology with Biostatistics minor)
University of Pennsylvania, 2002.
Links
Search PubMed for articles
Department of Biostatistics, Epidemiology & Informatics faculty page
Center for Pharmacoepidemiology Research and Training (CPeRT)
CCEB Faculty Page
NCBI Bibliography
Twitter
Permanent linkSearch PubMed for articles
Department of Biostatistics, Epidemiology & Informatics faculty page
Center for Pharmacoepidemiology Research and Training (CPeRT)
CCEB Faculty Page
NCBI Bibliography
> Perelman School of Medicine > Faculty > Details
Description of Research Expertise
Sean Hennessy leads Penn's Center for Real-world Effectiveness and Safety of Therapeutics (CREST). His research evaluates the real-world effectiveness and safety of prescription drugs using healthcare data. His research program studies serious health consequences of drug-drug interactions involving high-risk drugs including anticoagulants, treatments for diabetes, and medications used for opioid use disorder, and is widely cited in clinical compendia of drug-drug interactions. He and his colleagues identified a survival benefit of potassium supplements in users of loop diuretics, and found that this survival benefit increases with hotter outdoor temperatures. They also found that the survival benefit of statin drugs increases with hotter outdoor temperatures. His team also evaluated an early approach, known as drug utilization review, to using health insurance data to improve prescribing, finding it ineffective despite its federal mandate. This contributed to the omission of a requirement for drug utilization review programs in Medicare Part D. He co-led a pair of studies that demonstrated the effectiveness and safety of the SA14-14-2 vaccine for Japanese encephalitis (JE), which subsequently led to the immunization of millions of children per year in populous countries including Cambodia, India, Malaysia, Nepal, Sri Lanka, and Thailand. Use of that vaccine has been credited with reducing the worldwide incidence of JE. He and his colleagues also developed the instrumented difference-in-differences research design for studying the effects of exposures with marked time trends. He was the senior author of one of two citizen petitions to the US Food and Drug Administration that led to re-labeling of metformin, the best-proven therapy for type 2 diabetes at the time, to permit its use in the millions of persons with both diabetes and mild-to-moderate renal insufficiency. He has served as chair of NIH's Health Services and Organizational Delivery study section and its Health Services Quality and Effectiveness study section.Description of Other Expertise
Dr. Hennessy has served as scientific program chair and president of the International Society for Pharmacoepidemiology, regional editor for the journal Pharmacoepidemiology and Drug Safety, as a member of FDA’s Drug Safety and Risk Management Advisory Committee, and on the board of directors of the American Society for Clinical Pharmacology and Therapeutics. He is a co-editor of the books Pharmacoepidemiology, 6th edition and Textbook of Pharmacoepidemiology, 3rd edition.Additional Positions:
Director, Center for Real-World Effectiveness and Safety of Therapeutics
Director, Division of Epidemiology
Senior Scholar, Center for Clinical Epidemiology and Biostatistics
Senior Fellow, Leonard Davis Institute of Health Economics
Fellow, Institute on Aging
Member, Pharmacy and Therapeutics Committee, University of Pennsylvania Health System
Special Government Employee, US FDA
Member, Council for International Organizations of Medical Sciences (CIOMS) Work Group XIII on Real-World Data & Evidence in Regulatory Decision Making
Courses Led:
EPID 7050 Grant Writing & Scientific Writing
Honors:
1998 Stanley A. Edlavitch Award for Best Abstract Submitted by a Student, International Society for Pharmacoepidemiology
2002 Saul Winegrad Award for Outstanding Dissertation in Epidemiology and Biostatistics, University of Pennsylvania
2005 Young Alumnus Award, University of the Sciences in Philadelphia
2008 Leon I Goldberg Young Investigator Award, American Society for Clinical Pharmacology & Therapeutics
2013 Samuel Martin Health Evaluation Sciences Research Award, University of Pennsylvania Perelman School of Medicine
2014 Julius W. Sturmer Memorial Lecture Award, Alpha Tau Chapter of the Rho Chi Society, Philadelphia College of Pharmacy, University of the Sciences
2015 Elected Member, National Academy of Medicine
2024 William B. Abrams Award in Geriatric Clinical Pharmacology, American Society for Clinical Pharmacology & Therapeutics
Selected Publications
Chu PY, Kelly A, Hennessy S, Vajravelu ME, Huang J, Amaral S: GLP-1RA dispensing in youth With type 2 diabetes: 2020 to 2023. Pediatrics Page: e2025071971, 2026.Hsu Y-C, Thakrar AP, Leonard CE, Lowenstein M, Brensinger CM, Bilker WB, Bogar KF, Hennessy S: Trends in methadone use for pain and opioid use disorder among Medicaid enrollees. JAMA Health Forum 6: e244023, 2025.
Srivastava T, Harris RA, Bettigole C, Zhang H, Brensinger CM, Bogar K, Wang F, Nesoff ED, Bilker WB, Hennessy S: Stimulant overdose prediction model for Medicaid-insured persons. JAMA Health Forum 6: e253489, 2025.
Vo T-T, Ye T, Ertefaie A, Roy S, Flory J, Hennessy S, Vansteelandt S, Small DS: Structural mean models for instrumented difference-in-differences. European Journal of Statistics 18: 5132-55, 2024.
Bonnesen K, Heide-Jørgensen U, Christensen DH, Lash TL, Hennessy S, Matthews A, Pedersen L, Thomsen RW, Schmidt M: Comparative cardiovascular effectiveness of empagliflozin versus dapagliflozin in adults with treated type 2 diabetes: a target trial emulation. Circulation 150: 1401-11, 2024.
Chen C, Miano TA, Brensinger CM, Leonard CE, Bilker WB, Hennessy S: Risk of opioid overdose associated with concomitant use of methadone and statins. Clinical Pharmacology and Therapeutics 117: 421-26, 2024.
Torgersen T, Mezochow AK,Newcomb CW, Carbonari DM, Hennessy S, CT Rentsch, Park LS, Tate JP, Bräu N, Bhattacharya D, Lim JK, Mezzacappa C, Njei B,Roy JA, Taddei TH, Justice AC, Lo Re III V: Rates of severe acute liver injury after hepatotoxic medication initiation in real-world data. JAMA Internal Medicine 184: 943-52, 2024.
Golder S, Medaglio D, O'Connor K, Hennessy S, Gross R, Gonzalez Hernandez G: Reasons for discontinuation or change of selective serotonin reuptake inhibitors in online drug reviews. JAMA Network Open 6: e2323746, 2023.
Steinkamp J, Hecht TWH, Hennessy S, Leonard CE, Shu D, Airan-JCI S: Off-brand: A six-year study of medication brand and generic name usage in a multi-facility academic healthcare system. Journal of Hospital Medicine 18: 812-821, 2023.
Lo Re III V, Dutcher SK, Connolly JF, Perez-Vilar S, Carbonari DM, DeFor TA, Djibo DA, Harrington LB, Hou L, Hennessy S, Hubbard RA, Kempner ME, Kuntz JL, McMahill-Walraven CN, Mosley J, Pawloski PA, Petrone AB, Pishko AM, Rogers Driscoll M, Steiner CA, Zhou Y, Cocoros NM: Risk of admission to hospital with arterial or venous thromboembolism among patients diagnosed in the ambulatory setting with covid- 19 compared with influenza: retrospective cohort study. BMJ Medicine 2: e000421, 2023.
