Biomedical Graduate Studies

Description of Research Expertise

Sean Hennessy leads Penn's Division of Epidemiology and its 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, 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