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Drew Weissman, M.D., Ph.D.

Roberts Family Professor in Vaccine Research, Director of the Penn Institute for RNA Innovation, Director of Vaccine Research in the Infectious Diseases Division
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Dr. Weissman is the Roberts Family Professor in Vaccine Research at the Perelman School of Medicine, University of Pennsylvania and Director of the Penn Institute for RNA Innovations. He received his B.A. and M.A. from Brandeis University in Waltham, Massachusetts in 1981 and his M.D./Ph.D. from Boston University in 1987 before completing his medical Residency at Beth Israel Hospital in Boston, Massachusetts in 1990. He completed his Fellowship in Immunology at the Lab of Immunoregulation in the National Institute of Allergy and Infectious Disease of the National Institutes of Health, serving in the lab of Dr. Anthony Fauci. Following his Fellowship, Dr. Weissman became an Assistant Professor in the Division of Infectious Disease at the University of Pennsylvania in 1997. In 2005, he was promoted to Associate Professor, and to full Professor in 2012.
His major contributions to the scientific field include the identification of the mechanism by which RNA activates the innate immune system, and that naturally occurring modified nucleosides were the mechanism used by the cell to distinguish foreign RNA from self RNA. Further, Dr. Weissman and his colleagues identified that nucleoside modified mRNA not only did not cause inflammation, but that it was also more stable and efficiently translated than conventional mRNA and went on to develop nucleoside modified mRNA as a delivery system for therapeutic proteins. Building on this work, Dr. Weissman and his colleagues began using nucleoside modified mRNA complexed to lipid nanoparticles to deliver therapeutic mRNA as a vaccine platform, resulting in high titers of neutralizing antibodies against many different pathogens with minimal doses. In addition, Dr. Weissman and his collaborators analyzed the mechanisms that HIV envelope uses to suppress the immune system and proceeded to alter the envelope immunogen to improve responses against it when used in an encoding vaccine.
Dr. Weissman’s work has resulted in the publication of more than 100 papers. He holds many patents, including the ones which detail the modifications required to make mRNA suitable for vaccines and other therapies. In 2022, he was inducted into the National Academy of Medicine.
Hamideh Parhiz, PharmD, Ph.D.

Research Assistant Professor of Medicine
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Dr. Parhiz is a Research Assistant Professor in the Division of Infectious Diseases, Perelman School of Medicine at the University of Pennsylvania. She leads the targeted mRNA-LNP delivery program. Her research is mainly focused on developing a new generation of targeted mRNA-LNP therapeutics for a variety of non-vaccine applications such as acute inflammatory conditions, fibrosis, and cancer. She received her PharmD/Ph.D. in Pharmaceutical Biotechnology from Mashhad University of Medical Sciences in Mashhad, Iran, where she developed optimized Polyethyleneimine-based carriers for gene delivery. She joined Dr. Muzykantov’s lab at the University of Pennsylvania as a NIH T32 postdoctoral fellow in 2016 before joining Dr. Weissman’s lab in 2018. Her work has resulted in the publication of more than 40 papers and patents. Dr. Parhiz and her team’s main research goal is to provide safe and effective mRNA therapeutics for acute and chronic pathological complications.
Elena Atochina-Vasserman, M.D., Ph.D.

Adjunct Assistant Professor of Medicine
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Dr. Atochina-Vasserman is an Adjunct Assistant Professor of Medicine in the School of Medicine at the University of Pennsylvania. An expert in pulmonary therapeutics, Dr. Atochina-Vasserman joined the laboratory of Dr. Weissman in 2018, where she leads the project on novel delivery system to targeting mRNA therapeutics to the lung in vivo. She is also leading the project on developing mRNA vaccine for Norovirus.
Dr. Atochina-Vasserman began her research career focusing on targeting delivery of therapeutics to the pulmonary angiotensin-converting enzyme. She then completed her post-doctoral training at the Institute for Environmental Medicine at University of Pennsylvania under supervision of Dr. Aron B. Fisher and Dr. Vladimir Muzykantov, studying selective targeting of enzyme therapeutics to the lung for containment of oxidative stress and inflammation during ischemia-reperfusion. Following three years as a Research Associate in the laboratory of Dr. Michael F. Beers, Dr. Atochina-Vasserman was appointed as a Senior Research Investigator at the Pulmonary, Allergy and Critical Care Division at the University of Pennsylvania where her work was focused on lung host defense, inflammation, and innate immunity.
Dr. Atochina-Vasserman earned her M.D. from Tomsk Medical School, Russia and a Ph.D. from Cardiology Research Center, Moscow, Russia. Dr. Atochina-Vasserman is a peer reviewer in multiple scientific journals and grant applications (AHA, CEET at UPENN and Asthma UK Grants), her work has resulted in the publication of more than 60 papers (h-index 31) and several patents.