Transformative times, transformative leaders: An oral history of Penn Medicine’s pivotal path to prominence

Now—this exact instant—is a remarkable moment in the history of medicine. If you talk to any adult anywhere, any person in their 20s or older, about some of the real treatments available to patients today, then much of what you’re describing—gene therapy for blindness, making tumors glow for more precise removal, and re-engineering patients’ own immune cells to cure cancer—is something that was the stuff of science fiction when they were born.

Penn Medicine—this particular institution rooted in Philadelphia as home to both the nation’s first medical school and first hospital, now united as the University of Pennsylvania Health System and Penn’s Perelman School of Medicine—is an equally remarkable place, as the modern birthplace of so many of these spectacular biomedical firsts. Penn Medicine research has substantially contributed to 45 new U.S. Food and Drug Administration approvals for new disease treatments (and counting) since 2013. Among these were the first mRNA vaccines, which quelled a global pandemic, saved millions of lives, and earned the Nobel Prize.

Why here, and what ingredients did it take to make this avalanche of recent breakthroughs? Part of the answer is seen as an almost inevitable part of the ethos of Penn Medicine today—that the institution is united in purpose across all of the functions of academic medicine. Excellence in medical education and training uplifts excellence in research, and research drives innovation in the best care for patients, all in an ongoing virtuous cycle.

Another part of the answer, though, is that this unity in excellence at Penn Medicine owes a great deal to what came just a couple of decades before.

“Penn Medicine has emerged as a preeminent academic medical system over the past several decades largely because of the foundations laid by two of our former deans, Bill Kelley and Arthur Rubenstein,” said Jonathan A. Epstein, MD, dean of the Perelman School of Medicine and executive vice president of the University of Pennsylvania for the Health System. “Their vision set the stage for breakthrough therapies that have transformed the world, and created an expectation of excellence that continuously draws the brightest medical students and research trainees to learn at Penn and go back out to make an impact everywhere.”

On November 12, 2025, Epstein announced the rededication and naming of Penn’s Biomedical Research Building in honor of William (Bill) N. Kelley, MD, who led the institution from 1989 to 2000, and his late wife, Lois; and the rededication and naming of Penn’s Clinical Research Building in honor of Arthur H. Rubenstein, MBBCh, who led Penn Medicine from 2001 through 2011, who shares the building name with his late wife, Dr. Denise Rubenstein. Rubenstein received an additional honor when he was named this month as the winner of the 2026 Research!America Herbert Pardes Family Award for National Leadership in Advocacy for Research. This award recognizes individuals who have demonstrated distinguished academic leadership and sustained commitment to public engagement and advocacy for research.

For those who know Penn Medicine as it is today, it may look preordained or inevitable as a place that was home to such pivotal “firsts” in American medicine even before the nation’s founding. But those who lived through the past several decades and worked with these leaders say otherwise: There were crucial choices and turning points. There were investments and opportunities seized. There was a vision and a movement among people joining together to make that vision come to life.

“Bill Kelley believed that health care could be stronger if it worked as one. That belief became the foundation of Penn Medicine as we know it today,” said Kevin B. Mahoney, CEO of the University of Pennsylvania Health System. “And Arthur Rubenstein took that foundation and gave it life; he led, but more importantly, he inspired. He reminded us that excellence is not just about science, but also about people.”

In the following oral history, longtime faculty and other leaders from across the medical landscape reflect in their own words on the transformative times from the 1990s through early 2000s, and the key leadership choices that grew Penn Medicine into the eminent institution that it is today.

The late 1980s were a time at the precipice of massive change in medicine when the traditional healing arts, while already modern and evidence-based, began to converge with more basic biological discoveries of the underlying mechanisms of disease. By the late 1990s, scientists knew substantially more about the biology underlying many diseases than ever before, but questions of how to apply that knowledge to create new treatments, still constituted a so-called “valley of death” that was rarely bridged. In the 1990s, Penn Medicine skyrocketed from 10^th place in National Institutes of Health funding up to 2^nd, it has remained in the upper echelon of competitively funded research institutions ever since. The timing mattered—when crucial decisions to invest in the leading edges of medicine helped Penn Medicine position itself at the forefront of, and ultimately as a driver of, these rapid transformations.

Glen Gaulton, PhD (vice dean for global health who previously served as chief scientific officer for 15+ years): I was in graduate school in the early 1980s, and at that point, one human gene had been isolated and described. Only one. And yet by the ‘90s, dozens and dozens of genes had been described…. then as we started to understand the molecular structure of genes and the basis of how genes control cell and organismal function, that opened up an entirely new field of medicine.

Jean Bennett, MD, PhD (pioneering gene therapy researcher in ophthalmology): It was a really early time in the field which is now known as gene therapy. We didn’t know most of the genes. We didn’t have models for the genes. We didn’t know how to deliver them or what the safety parameters were.

Michael Parmacek, MD (cardiologist, researcher, and director of the Penn Cardiovascular Institute since 2005 and chair of Medicine since 2015): Bill [Kelley] really lit the fire under Penn. Bill recognized that Penn had a rich history. It was the first school of medicine and had many, many years of achievement. But it wasn’t the institution he wanted it to be.

William N. Kelley, MD: I truly believed at that time that gene therapy in the 21^st century was going to be as important as antibiotics were in the 20^thcentury.

Gail Morrison, MD (nephrologist and vice dean of medical education from 1995 through 2018): [Bill Kelley] was very innovative. He was very creative. He was very visionary. He was very inspirational. He recognized when things had to change, and he did not let anything stand in his way in order to make those changes.

Gaulton: It was like somebody grabbed you by the collar and dragged you into a new era—the era of molecular medicine.

Bennett: [Dr. Kelley] realized that this was going to be a long process and wanted to invest in it. And it's because of his interest in promoting this research that there has been so much progress in treating diseases from a genetic perspective.

Gaulton: Arthur [Rubenstein]’s great strength was in advancing what is now popularly called translational science. This was built on Penn’s growing prominence in molecular biology paired with the inherent synergy of our school and health system.

Arthur H. Rubenstein, MBBCh: I never thought that we should be known primarily for our basic science. We should have great basic science, but basic science in a medical center should inform research for patients. How do we cure disease? How do we make things better for patients? I always had that as the integrated dream to have basic science and clinical research in the same area where they were not separate entities.

Francis S. Collins, MD, PhD (former director of the National Institutes of Health and former mentee of Kelley): Penn saw [a focus on molecular biology and its applications to therapies] as the sweet spot for the era that we’re [now] in the middle of. And building skills and capabilities in that space provided a magnet for trainees and other junior faculty to come and be part of that. That’s kind of the signature of Penn Medicine, in the minds of many of us: the focus on molecular biology, cell therapy, gene therapy taken from the bench to the clinic. And then what you learn at the clinic, you take back to the bench and you make it better…. [Bill Kelley and Arthur Rubenstein] building that together made this whole pipeline from basic science discovery to [now 45] FDA approvals of therapeutics, a reality. I don't know any other institution that had that kind of coherent, synergistic plan about how to advance human medicine the way that Penn did under their leadership.

Victoria Mulhern (longtime leader of faculty affairs): My position gave me the opportunity to be part of the faculty recruitment and appointment process. They numbered probably around a thousand when I started [in 1996], and about 4,500 when I retired [in 2021]. So it became an absolutely booming center for discovery, across clinical areas, research areas, and also in innovative teaching areas.

Bennett: [Bill Kelley] attracted a very large number of talented people who had the same really incredible, dazzling ambitions to try to develop treatments which would stop a disease at its root, i.e. the genetic basis of the disease. There really was no precedent for this. This was way out there and almost science fiction-y. But he believed that this was possible and allowed people like me, and many others, to try it out.

Parmacek: It’s the resilience. It’s the vision. It’s the boldness in their vision. And that’s what the two of them were exceptionally good at recognizing in people.

Gaulton: Arthur tended to recruit individuals who were more collegial, and individuals that could weave the fabric of what we did together, which was a reflection of his vision for the entire institution.

Rubenstein: I always wanted to say we could be the best there was, and that was irrespective of me. It was just that I recognized [the best people to recruit]. And so when they came, there was no credit to me; the credit was all theirs. But they felt part of this culture we created and most of them thrived in that kind of atmosphere. Everybody felt they could contribute to the best of their ability, and most of them did. And that made the place, which was very good—that made it really great.

Morrison: For those of us that came into medicine in the 1970s, nobody could ever have dreamt about doing some of the things that we are now doing related to genes, to CRISPR, to CAR T, to mRNA vaccines… None of this would have happened without [Kelley and Rubenstein both] bringing in the kinds of people they brought in. And they stood by things even when people told them it wasn’t going to be successful.

Bennett: It took 17 years from the point where we had proof of concept in an animal model in the laboratory, [until we showed] that we could actually reverse blindness in children and adults with an inherited form of blindness. Then it encouraged other groups to take off. And now there are more than half a dozen FDA-approved treatments for different genetic diseases.

Rubenstein: [My father, a Jewish refugee,] landed up in South Africa before the First World War, speaking only Polish. His mother had died in a pogrom in Warsaw. He wanted to be a doctor, but he didn’t have the money or the language ability to do that. So he became a pharmacist because he could work at night and learn English during the day. He was a great role model for me because I saw what hard work and commitment looked like, and he really believed in education.

Kelley: Our mission was to promote, simultaneously, the three pillars of the academic health system: education, research, and patient care…. [I always list them] in that order, recognizing that the first mission of any academic medical institution is to educate and train the next generation of leaders in medicine and science.

Morrison: Having basic researchers come into the school and show students what they're doing and why they're doing it, and how really exciting it is, was critical [among Curriculum 2000 innovations]. The same thing goes for clinicians… [Now] everybody has some role in the School of Medicine teaching, even if you are a clinician full-time or a researcher full-time. And that's why having the Penn Medicine integrated system was so critical.

Parmacek: Bill and Arthur really understood that what made Penn special was the integration of science with medicine, with education. And it was the sum of those three different missions that really distinguished Penn Medicine from other top-tier organizations.

Kelley: I often used the phrase, “You cannot educate and train students, residents, and fellows on empty beds,” nor can you effectively conduct clinical research. That understanding was the rationale for the Health System.

Rubenstein: How do you integrate the missions of a complex organization so that they enhance each other? Education, clinical patient care, basic science, and clinical research, those four modalities in many, many places, they are very separate or they only interplay a little bit. But I had the belief that if we could integrate them really fully, that would make each of them uniquely better. And that was a dream I had [since I was a medical student]. And when I came to Penn, I thought there was a chance to do that. It wasn’t obvious we could do it, but there was a chance we could do it.

Kathryn Griffo (Penn vice president for Development and Alumni Relations, formerly chief advancement officer for Penn Medicine): That ambitious goal of integrating research, education, and patient care missions attracted many donors who had a new opportunity to make a gift that was truly meaningful and impactful to them. Our donors and alumni felt engaged as partners in shaping Penn Medicine’s future.

Rubenstein: Ralph Muller’s role [as CEO of the Health System from 2002 to 2019] was really, really important, and our partnership was very special. He had the same vision as I had in terms of what made a health system, with science and education together with great clinical care. We gradually put the finances back in order, and then after that the health system thrived, and we were able to send all the money back to the university that they had loaned, with interest, and we were happy to do that because we were a great part of a great university.

Bennett: I think one of the most amazing aspects of Penn Medicine is that there is so much talent here that it's really easy to find collaborators in different fields, and even working with people in the law school or the dental school or the vet school.

Rubenstein: I wanted us to be an integral part of the university where both the university would be proud of us, and we would contribute in a positive way, not just financially, but more intellectually and as a partner. And the two university presidents who I worked under, President [Judith] Rodin and President [Amy] Gutmann, they believed in that implicitly.

Gaulton: Arthur’s legacy is a baseline expectation that we’re all together in this and that we work seamlessly between the academic and the clinical side. It’s something that we now all take for granted. His legacy is the cohesiveness of our institution, which is a fundamental property and identity of Penn Medicine.

Rubenstein: We had very strong basic science which Bill Kelley was a leader in recruiting. But I took that basic science, which was excellent, and tried to focus it on patient care, and disease-oriented research. Things like CAR T cells, David Fajgenbaum’s work on Castleman’s disease. These have all come out of science related to patients and patients’ diseases, and that’s what I think a medical center can do as opposed to a research institute. We developed institutes to take advantage of that: We already had the great Abramson Cancer Center, and then the Institute for Diabetes, Obesity, and Metabolism, the Institute for Translational Medicine and Therapeutics (ITMAT), and the Cardiovascular Institute, they were integrated as an expression of that goal, connecting basic science to treating disease. And that’s what I think we have become known for.

Collins: When I was NIH director, for 12 years, I could look around and see which of the institutions that are really just focused on themselves, and which are the ones that are really interested in being part of a network [and learning collaboratively with peers across the country]. The way that Garret FitzGerald managed ITMAT was a golden example of how to take that resource and turn it into a leader on the national scene. All of the other [NIH-funded] clinical [translational research] centers linked up and many of them [are] learning things from Penn, because Penn really had thought about how to do the boldest and the most significant clinical research.

Kelley: Resources in the form of first-rate educational, research, and clinical space and facilities were required to attract those [world-leading] teachers, scientists, and physicians to Penn. It took a total team effort to achieve this.

Griffo: Bringing new life and excitement to our historic campus attracted outstanding faculty and a growing forward-thinking community interested in supporting their work—Leonard and the late Madlyn Abramson’s landmark gift to create the Abramson Family Cancer Research Institute immediately comes to mind. Arthur’s vision and commitment to translational medicine then changed how our philanthropic partners thought about biomedical research. You could begin to see tremendous possibility and power at the intersections of our missions.

Gaulton: Under Arthur’s leadership, the literal foundations, the structural facilities that were created to support translational science, were laid during his time. And the best examples are what we see now on Civic Center Boulevard.

Rubenstein: The first thing I wanted to do was build an outpatient building. I think the Rhoads building, which was an inpatient building, was the last one built, which was great for inpatients. But outpatients were being done in the Hilton Hotel relic, and scattered throughout different floors of HUP. And I always believed that the heart of patient care was a beautiful outpatient building.

Griffo: Our donors appreciated and wanted to be part of this comprehensive vision taking shape, starting with the Ruth and Raymond Perelman Center for Advanced Medicine, Roberts Proton Therapy Center, and their many programs.

Rubenstein: Then they wanted to build an education building further down Convention Ave. And I said, no, no, no, no, we can't do that. We have to have it right in the middle of research and patient care. And so then we raised money from Barrie Jordan, and Ralph Muller and [now Health System CEO, then executive vice president] Kevin Mahoney and I worked out, we’d put it right in the middle of everything. And then I thought: This is my dream, patient care, research, and education all together. What could be more great?

Griffo: The power of Penn Medicine’s integrated missions set the stage for the connectedness of our growing campus, from the Henry A. Jordan, M’62 Medical Education Center to the Smilow Center for Translational Research and capped by The Clifton Center for Medical Breakthroughs. Donors and alumni were excited by this historic moment to help build and sustain everything Penn Medicine could become.

Parmacek: If you look up and down University Avenue now, you really see one of the major academic medical centers in the country with world-class facilities that really weren’t here 20 years ago.

Rubenstein: We were also working alongside the greatest children’s hospital in the country, Children’s Hospital of Philadelphia. It was important to me that we work to integrate ourselves, and now Penn and CHOP are not just neighbors, but powerhouses around the country in so many shared discoveries and impacts.

Griffo: This campus is such a powerful symbol of the Penn Medicine approach—and it also represents the partnerships across faculty, health care teams and researchers, students and trainees, and the donor and alumni community who are transforming that symbol into world-class medicine.

Rubenstein: It doesn’t often happen that you can expedite your vision, but having all the young people run around next to research and patients in the same building where doctors didn't have to go too far to do [research and care for patients], and then we added The Clifton Center. It was unique. We were able to do that because of the great university presidents we had, both Judith Rodin and Amy Gutmann, and also the structure that Bill Kelley had set up, which I give him enormous credit for, in which the EVP was head of the health system as well as research and education. Most places aren’t like that, bringing everyone together by design.

The people, the places, and the connectedness of purpose across Penn Medicine’s missions: Together, these principles represent a major foundation of why Penn Medicine has been the home to such profound benefits to the world through lifesaving discoveries. Penn Medicine today also embraces a fourth interconnected mission area, which is to improve the health and well-being of the communities we serve. But in the continued pursuit of making the world a better place, there is one more key element in how Penn has sustained its place at the forefront. That is a culture of collaboration and a shared belief in that purpose among the people whose work continues, day after day.

Mulhern: My whole tenure here at Penn Medicine, there was an electricity in the air. You can even tell who works for Penn Medicine. When you go over to the medical center, you’ll see who’s walking the fastest, because those are the people working for Penn Medicine.

Gaulton: Many of the faculty who are here now, weren’t here under either Dr. Kelley or Dr. Rubenstein. And yet they’re benefitting from the legacy that Bill and Arthur set in terms of highest quality care matched with highest quality research—all of that underpinned by the expectation that we should continually expect more of ourselves to generate an exceptional institution producing meaningful impact.

Rubenstein: What I’ve always tried to do, going back to my days at the University of Chicago and even in South Africa, I’ve tried to build a culture of support, kindness, and respect for people of all levels in the organization. Whether it's the cleaning staff or the students, faculty, administrators and board of trustees, I always try to create an atmosphere where everybody could feel comfortable and thrive.

Gaulton: It’s wrong to think about Arthur just as a healer, which I think is how most people see him. He was an incredible strategist…. Yes, he brought us together as individuals, but from a strategic perspective he catapulted the institution into the world leader of translational science.

Griffo: Arthur’s talent as a leader—and especially his character, as a human being—helped grow this singular, remarkable Penn Medicine culture that everyone could feel was different and special. It’s inspiring and creates so much hope, and I think it’s why Penn Medicine has the longevity and breadth of the donor and alumni relationships we enjoy today. It’s why [the late] Ruth and Ray Perelman chose to grow their support of our institution over the years, culminating in the extraordinarily generous act of naming the Perelman School of Medicine. Our donors and alumni are proud to be part of a positive force for the health of the world.

Rubenstein: Collaboration brings out the best in everyone, in my opinion. Whether it was between clinicians and scientists, students and faculty, the administrative staff, nurses and doctors, collaboration makes an institution great. We were able to create that culture where that was rewarded.

Collins: It’s always hard to say exactly what factors play out in achievements that lead to massive scientific advances, because people are always standing on the shoulders of others. But when you look at, for instance, what’s happened with CAR T cells, the way in which Carl June’s leadership in that space has created a whole field of cancer research and cancer clinical practice that has now saved countless lives, that’s a Penn contribution for the ages. And, of course, right there at Penn, the development over 25 years of hard work on the mRNA approach to vaccines, which we believe saved something in the neighborhood of 3.1 million lives in the United States alone from COVID-19 and maybe 14 or 20 million worldwide…. [That work led to] Nobel Prizes, well-deserved for [Katalin] Karikó and [Drew] Weissman,and something that I think history will look back on as potentially the most significant example of scientific contributions to humanity and to humanity’s survival.

Rubenstein: And here we are in Philadelphia with, I would say, one of the greatest medical systems and universities in the world. It’s pretty quick and pretty amazing. I’m pretty proud of all that.