Gunnar Tepe, professor of Radiology, Department of Diagnostic and Interventional Radiology, Klinikum Rosenheim, Rosenheim, Germany, was involved in the development of the first drug-coated balloons for the treatment of peripheral arterial disease. Principal investigator in the THUNDER trial, in 2007 he presented the first-in-man results with a paclitaxel-eluting device. Tepe, who is also principal investigator of the IN.PACT SFA trial, tells Vascular News about his career, drug-eluting balloons research and interests outside medicine including the refurbishment of an old farm house in the German countryside.
When did you decide you wanted a career in medicine? Why did you choose interventional radiology?
When I was young I thought of different possibilities such as architecture and biochemistry but medicine was also in my mind. In order to test if medicine would be something to be considered, I worked in a hospital during school holidays. Later, during military service I worked in a hospital and became an ambulance man. During all this time I became more and more aware that I had to go to a medical school.
Who has inspired you in your career and what advice of theirs do you remember today?
When I finished the medical school in Berlin I did not think of becoming an interventional radiologist—in the beginning my idea was to specialise in paediatrics. Nevertheless it was very difficult do get a job in this area. In addition, I was told that it was not wise to go into such an overcrowded speciality. Therefore I started internal medicine at the University Hospital in Tübingen. However, the circumstances in the department I started were not satisfactory. At that time I had some contact with radiology. I was impressed by the huge range of possibilities and also by the great team around Prof Claussen and Prof Duda. In fact, Prof Duda asked me if I would consider joining their team. He offered me to do basic research in a lab followed by clinical work. That was the best decision I have taken. Before I started in the lab I was not sure if I would be good enough for science work but just a few weeks later I realised that science would change my life. I have learnt a lot form Prof Duda who was always perfectly organised. I learnt to raise the right questions and the possible solutions that might be interesting in the future. Furthermore, he taught me how to perform endovascular therapy. After he left for a major position in Berlin, I took his role at the University of Tübingen leading interventional radiology.
What have your proudest moments been?
The far most moving moment was the day our daughter Zoé was born. She is now five years old and the most important thing in our lives. In my medical career I remember two major moments. In 2003 I received the Wilhelm Conrad Roentgen Prize of the German Roentgen Society for the development of a radioactive stent for prevention of restenosis. In the development of other devices for the prevention of restenosis that were easier to use I had the honour to work with Prof Speck, Dr Muschik and Prof Scheller. We had the idea to develop drug-coated balloons. No major company was interested in our proposal and it was very difficult to raise the money for a clinical study which I called the THUNDER trial. In 2007, I got the opportunity to present these first-in-man data as a late-breaking trial in front of several thousand delegates at TCT. A few months later the data were published in the New England Journal of Medicine. In the meantime, therapy with drug-coated balloons has become a standard of care.
How has interventional radiology evolved since you began your career?
When I started interventional radiology, endovascular therapy was used for simple lesions only. At that time the first self-expanding stents were introduced. Nowadays, endovascular therapy is a stand-alone therapy in most patients. Also, because of further development in terms of devices, success rates and long-term results are much better compared to the first days.
What have been your most memorable clinical cases?
There are many. I remember a patient who received an aortic prosthesis due to a rupture after an accident while paragliding in the Alps. He was brought to our hospital at Rosenheim a few months after I started to work here. At that time we had no aortic stent grafts stored in our hospital. The devices for the case were despatched to us on a taxi from Munich—and the patient survived. Another case was of a patient who received one of the first drug-coated balloons used in Rosenheim. During a follow-up angiography he told me that he was very lucky that he could again do the things that were so important in his life: walk on the mountains and stay in a hut. Because this type of statement was repeated by a lot of other patients, we started an event: a walking tour with all our patients to a mountain hut—those patients who were not able to walk before. For the past five years, each end of summer, we have walked with a group of approximately 150 patients. This is an important event for all of us.
You were the principal investigator of THUNDER and also of IN.PACT SFA, which had the results presented for the first time in April. How do you compare the results with drug-eluting balloons in these two trials?
THUNDER was the first study which could show the safety and efficacy of drug-coated balloons in peripheral arterial disease. This was a first-in-man study done in a few centres in one country only. IN.PACT SFA has also shown great results. Because of the study design, with more than 50 centres involved, and the way the study was undertaken with 100% source data verification, a safety monitoring board and core labs analysing all data, the level of evidence reached in this trial was even higher.
What have you seen so far in patients treated in the DEFINITE AR trial? Does debulking before drug-eluting balloon have a role?
I cannot completely answer this question because the one-year data have not been fully analysed yet. Nevertheless, I personally think that there is a need to prepare vessels for drug uptake especially in heavy calcified vessels. Because at least in the randomised arms in DEFINITIVE AR heavily calcified arteries were excluded, it might not be possible to draw a final conclusion from this study.
The results of IN.PACT SFA were very positive, but the results of IN.PACT DEEP led to the discontinuation of the Medtronic device below the knee. Is there a future for drug-eluting balloons below the knee?
I strongly believe that there is a need for drug-coated balloons in below-the-knee arteries because the restenosis rate is very high, especially below the knee. However, several issues for the use of drug-coated balloons in patients with below-the-knee disease and ulcerations have to be addressed. First of all, devices with a sufficient drug transfer to the vessel wall are needed—high paclitaxel concentrations due to loss of the coating in patients with non-healing ulcers might be an issue. In addition, because of the diffuse calcification of these arteries, a preparation for drug uptake might be mandatory.
You are involved in a trial comparing the use of drug-eluting balloons and drug-eluting stents in long femoropopliteal lesions. What have the results shown?
This study was led by the group of Prof Zeller. We have showed that drug-eluting balloons might be as effective as drug-eluting stents in long superficial femoral artery lesions.
What other topics are you researching at the moment?
My special interest is in further development of local drug delivery for prevention of restenosis. Another interesting approach is the use of resorbable stents.
What is the most interesting paper you have come across recently?
Because if my interest in drug-coated balloons I am very impressed by a lot of studies which have been recently published in this area.
What skills does the interventionalist of the 21st century need to develop?
Because the development is very rapid, everybody working in this field has to update their knowledge on a constant basis. Besides that, interdisciplinary work is fundamental.
Outside of medicine, what are your interests?
Outside medicine my family comes first. Together with my wife Sabine, seeing our daughter Zoé growing and learning is a tremendous luck. Beside this we have currently a huge project. We are rebuilding an old farm house from the 15th century. We had to learn also that this is not all fun. Besides this we like to go hiking on the Alps which are really near to us. Since childhood I love skiing and I used to jog on a regular basis. I hope that this will be possible again in the future. In addition, travelling is always fun. We go long-distance, but we also love driving around with our camper van and staying wherever we feel like stopping.
Professor of Radiology, Department of Diagnostic and Interventional Radiology, Klinikum Rosenheim, Rosenheim, Germany
Education and professional training
1972–1985 Gymnasium Am Barkhof in Bremen, “Allgemeine Hochschulreife” (A-level) 13.06.1985 St Bede’s College, Upper Dicker, Sussex, UK (Jan–Mar 1985)
1986–1993 Medicine at the University of the Saarland in Homburg/Saar (1986–88) and the Free University Berlin (1988–1993), Germany. Practical training at the University of Maryland, USA, Department of Pediatrics-Cardiology (Jul–Sep 1990), and the University of Sydney, Australia, The Childrens Hospital (Oct 1992–Jan 1993)
1993–1994 Internal Medicine at the University of Tuebingen, Germany (Gastroenterology, Prof Dr med G Gregor),
1995 Approbation date (4th January)
1995– Radiology at the University of Tuebingen, Germany (Prof Dr med C D Claussen)
1995 Medical Thesis “Characterization of IgE Epitopes on Ovalbumin in Children with Egg Allergy” (Prof Dr med U Wahn, Free University of Berlin, Germany)
2001 Master’s Degree in Diagnostic Radiology
2003 “Habilitation”; Assistant Professor of Radiology “Prevention of restenosis with radioactive labeled stents in a rabbit model of atherosclerosis and thrombogenicity tests”, Oberarzt
1997 Head of the Laboratory of Experimental Interventional Radiology, University of Tuebingen, Germany
Study chairman of several clinical prospective multicenter trails (PROMPT, APART, BELOW, Thunder, Napa-2*) and co-investigator in the RELAX*, SIROCCO, and FAST TRIAL (*FDA)
2006Professor of Radiology, Leitender Oberarzt
2009– Head, Department of Diagnostic and Interventional Radiology, Rosenheim
2010– General principal investigator of clinical trials eg. SFA 1 (FDA), In.Pact Global (FDA), Copa Cabana, Advance-18, Biolux PIII, DEFINITIVE AR, Consequent, and local principal investigator in studies such as STANCE, Biolux P1, Sprint and Illuminate
Konrad Wilhelm Roentgen Prize 2003
Fortschritte auf dem Gebiet der Roetgenstrahlen und der bildgebenden Verfahren (ROEFO), Investigative Radiology, Journal of Endovascular Therapy and CVIR
Deutsche Roentgengesellschaft (German Roentgen Society)
Cardiovascular and Interventional Radiology Society of Europe (CIRSE)
Bavarian Roetgen Society
Participant or principal investigator in more than 50 clinical studies over the past 18 years