For a healthier world

What does Quercis Pharma do?

Quercis Pharma AG is leveraging its novel antithrombotic, anti-inflammatory and antiviral platform to deliver innovative, safe, and broadly accessible treatments to patients with potentially life-threatening conditions.


Our focus is on prevention of venous thrombosis and pulmonary embolism in high risk cancer patients with our drug candidate Kinisoquin™, containing our patented Isoquercetin formulation.


The safety of our investigational drug has been proven in various studies, with no serious side effects having been identified, in particular our drug shows no increased bleeding risk.


A clinical Phase 2 study has shown that Kinisoquin™ reduced hypercoagulability in cancer patients at high risk for thrombosis with an improved benefit/risk ratio.


Our novel pathway is based on a new mechanism of action, in order to arrest and/or reverse platelet aggregation with a profile that conveys vastly lowered bleeding risk compared to current standard of care.


We control both the raw material production and the Active Pharmaceutical Ingredient (API) manufacture for our investigational drug Kinisoquin™.


The humanitarian aspect of the Company is to look at treating global diseases in less privileged populations and to work with Governments and NGOs to improve healthcare in countries where they find it difficult to pay for development or production of new drugs to combat critical health threats such as Sickle Cell Disease and viruses such as Ebola and Zika.



Quercegen Pharma LLC is formed and enters into many research collaborations with DARPA, AFFRI, CFD (U.S. Army), THE COCA COLA COMPANY, PEPSICO and leading institutions, universities and hospitals around the world.

Merck KGaA’s Natural Products business, farms and production units purchased and integrated.

Nutravail purchased 2009 in JV with PepsiCo.

More than a decade of research and development focusing on flavonoid extraction, manufacture and naturally occurring small molecule formulations.

2019 onwards

Quercis Pharma AG is formed and based in Zug, Switzerland.

Quercegen Pharma Pharmaceutical Assets, Clinical Programs and Patents assigned to Quercis.

Quercis takes ownership of FDA IND of the successfully completed Phase 2 trial in VTE prevention in advanced metastatic cancers.

Successful End-of Phase 2 / Phase 3 protocol discussion with FDA and FDA SPA achieved for first Phase 3 Program.

Preparation of API and Clinical Materials for Phase 3 Clinical Trials.

Journal of Clinical Investigation

Kinisoquin™ (our Isoquercetin-based drug candidate) reduces coagulation markers in patients at risk of thrombosis

Drug Development


  • Isoquercetin patented formulation (Kinisoquin™)
  • Isoquercetin prevents platelet activation and initiation of the thrombotic cascade.
  • Over 20’000 publications referencing Isoquercetin and Quercetin in multiple indications
  • Safety profile of Kinisoquin™ (our main investigational drug) is well established. It has been shown not to increase bleeding risk – a significant advantage over Heparins and Direct Oral Anticoagulants

Lead indication: VTE prevention in cancer

  • Venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE), is an important cause of morbidity and mortality among patients with cancer.
  • Besides increased risk of VTE, advanced cancer patients have a significantly increased bleeding risk.
  • Major bleeds are a side effect of today’s anti-coagulants (ACs).
  • As a result, Venous thromboembolism (VTE) prevention remains limited for advanced cancer patients, despite these patients being at a high risk of VTE.
  • Currently, anticoagulant use is not recommended prophylactically to cancer patients due to significantly increased bleeding risk.
  • Kinisoquin™ is expected to prevent VTE effectively without increased risk of bleeding in advanced cancer patients.

Pipeline indications

  • Reduction of tumor metastasis
  • Treatment of Ovarian Cancer
  • Treatment of Ebola
  • Treatment of COVID-19 and related Viral Illness
  • Treatment of Sickle Cell Disease (SCD)
  • Treatment of Amyotrophic Lateral Sclerosis (ALS)
  • Test for Thrombosis Risk


Scientific Advisory Board

Dr Jean-Pierre Bizzari is a world-renowned oncology expert with over 35 years of broad experience in oncology drug development. He is former CMO of Celgene where he presided over the registration of drugs including Abraxane, the frontline therapy for pancreatic cancer, Revilimid, Vidaza, Istodax, and Taxotere. Dr. Bizzari is a member of the European Organization of Research and Treatment of Cancer (EORTC), Chairman of EORTC’s New Drug Advisory Committee, and a member of the Scientific Advisory Board of the French National Cancer Institute. He is Professor emeritus of Pathology at Harvard Medical School, and he was a member of National Institute of Health (NIH) expert panels, and of the medical Board of the American Asthma Foundation in the USA.

Dr Flaumenhaft is Division Chief of Hemostasis and Thrombosis and Professor at Harvard Medical School. Dr Flaumenhaft’s laboratory has subsequently made major contributions to the understanding of the mechanism of platelet granule release and its role in thrombus formation. He holds dual board qualifications from the American Board of Internal Medicine.

Dr Barbeito is a former director of the Pasteur Institute in Uruguay. He directs the Laboratory of Neurodegeneration at Pasteur, Montevideo and performs research on the cellular and molecular mechanisms of brain aging.

Dr Hidalgo is a world renowned oncologist and specialist in pancreatic cancer. He is Professor of Medicine at Cornell Medical School and Chief of the Division of Hematology and Medical Oncology at Weill Cornell Medicine and New York-Presbyterian/Weill Cornell Medical Center. He also is Deputy Associate Director for Clinical Sciences at the Dana-Farber, Harvard Cancer Center, and a Member of the Board of PANCAN. He has authored more than 220 articles in top tier peer-reviewed journals.

Board of Directors

Ilias joined Quercis Pharma AG in 2019 as co-owner, CEO and Chairman. After advancing the company for two years, he stepped out of the operational leadership role in April 2021. Before Quercis, Ilias was a partner at Cevian Capital, Europe’s largest public equity activist fund, and before that, he had been with McKinsey & Company. Ilias holds a MSc in Electrical and Business Engineering from ETH Zurich, a Ph.D. in Corporate Finance from the University of Zurich, and a Certificate in Corporate Governance form INSEAD.

Thomas founded Quercis and its predecessor company Quercegen Pharmaceuticals, which acquired the Merck Natural Products Division 2009. He has been the driving force behind the successful development of Quercis’ drug development program. Thomas is a serial entrepreneur, scientist and successful inventor, who has registered multiple drug patents and trademarks. He is the world’s leading expert on naturally occurring small molecules as disease prevention agents with a specific emphasis on Flavonoids.

Philippe is the former French Minister for Health, a former member of the European Parliament and a United Nations official who has served as Under-Secretary-General of the United Nations and chairman of UNITAID. He studied medicine in Toulouse, became Professor of Medicine at Toulouse Sciences University in 1988, and since 2016, he has also been a visiting Professor at the Harvard T.H. Chan School of Public Health.

Simone is professor at ETH Zurich, where she heads the Responsive Biomedical System Lab, developing diagnostic and therapeutic systems at the nano-scale with the aim of tackling challenging problems in medicine. She researched at MIT on nanosensors for in vivo tumor profiling and on methods to wirelessly enhance drug transport. She is a recipient of several awards, such as the Prix Zonta in 2019 for Women in Science, and was honored with the distinction of “Young Scientist” by the World Economic Forum (WEF) for her scientific contributions to society. She earned her PhD degree in microrobotics at ETH Zurich and holds a masters in industrial engineering from the Karlsruhe Institute of Technology.

Executive Team

Thomas founded Quercis and its predecessor company Quercegen Pharmaceuticals, which acquired the Merck Natural Products Division 2009. He has been the driving force behind the successful development of Quercis’ drug development program. Thomas is a serial entrepreneur, scientist and successful inventor, who has registered multiple drug patents and trademarks. He is the world’s leading expert on naturally occurring small molecules as disease prevention agents with a specific emphasis on Flavonoids.

Stefan has over 35 years of experience in the pharmaceutical and biotech industry. Before joining Quercis he was Chief Medical Officer and Head of R&D at Vifor Pharma with responsibility for preclinical and clinical R&D, regulatory and medical affairs as well as drug safety. Prior to that he was Head of Clinical Research at Novartis OTC and worked 20 years at Bayer in R&D. Stefan holds a Medical Doctor’s degree from the University of Düsseldorf, Germany.


Lead indication: VTE prevention in cancer

Zwicker JI, Schlechter BL, Stopa JD, et al. Targeting protein disulfide isomerase with the flavonoid isoquercetin to improve hypercoagulability in advanced cancer. JCI insight 2019;4.

Wang TF, Zwicker JI, Ay C, et al. The use of direct oral anticoagulants for primary thromboprophylaxis in ambulatory cancer patients: Guidance from the SSC of the ISTH. J Thromb Haemost 2019.

Stopa JD, Neuberg D, Puligandla M, Furie B, Flaumenhaft R, Zwicker JI. Protein disulfide isomerase inhibition blocks thrombin generation in humans by interfering with platelet factor V activation. JCI insight 2017;2:e89373.

Abu Saadeh F, Norris L, O’Toole S, Gleeson N. Venous thromboembolism in ovarian cancer: incidence, risk factors and impact on survival. Eur J Obstet Gynecol Reprod Biol. 2013 Sep;170(1):214-8.

Shafabakhsh R, Asemi Z Quercetin: a natural compound for ovarian cancer treatment. J Ovarian Res. 2019 Jun 15;12(1):55. doi: 10.1186/s13048-019-0530-4. Review.

Ay C, Simanek R, Vormittag R, et al. High plasma levels of soluble P-selectin are predictive of venous thromboembolism in cancer patients: results from the Vienna Cancer and Thrombosis Study (CATS). Blood 2008;112:2703-8.

Pipeline indications

Yi L, Li Z, Yuan K, Qu X, Chen J, Wang G, Zhang H, Luo H, Zhu L, Jiang P, Chen L, Shen Y, Luo M, Zuo G, Hu J, Duan D, Nie Y, Shi X, Wang W, Han Y, Li T, Liu Y, Ding M, Deng H, Xu X. Small molecules blocking the entry of severe acute respiratory syndrome coronavirus into host cells. J Virol. 2004 Oct;78(20):11334-9.

Lili Chen et al. 2006. Binding interaction of quercetin-3-b-galactoside and its synthetic derivatives with SARS-CoV 3CLpro: Structure–activity relationship studies reveal salient pharmacophore features. Bioorganic & Medicinal Chemistry 14 (2006) 8295–83.

Khaerunnisa, S.; Kurniawan, H.; Awaluddin, R.; Suhartati, S.; Soetjipto, S. Potential Inhibitor of COVID-19 Main Protease (Mpro) From Several Medicinal Plant Compounds by Molecular Docking Study. Preprints 2020, 2020030226 (doi: 0.20944/preprints202003.0226.v1).

Nguyen et al 2012. Flavonoid-mediated inhibition of SARS coronavirus 3C-like protease expressed in Pichia pastoris. Biotechnol Lett 2012;34:831–8.

Press releases

Press Release – 04 May 2021

Press Release – 12 April 2021

ZUG, SWITZERLAND, March 5, 2021 – Quercis Pharma AG will participate in the upcoming HC Wainwright Global Life Sciences Conference taking place virtually from March 9-10, 2021. Ilias Läber (CEO) and Stefan Wohlfeil (CM) will deliver a corporate overview in a webcast presentation that will be available on-demand as of 6:00 a.m. EST, Tuesday, March 9, 2021 through 5:00 p.m. EST, Wednesday, March 10, 2021. Please register here to view the webcast.

Press Release – 5 March 2021

Press Release – 21 January 2021

Press Release – 11 November 2020


Quercis Pharma AG is a private, biopharmaceutical company based in Zug, Switzerland. Quercis Pharma is advancing a development pipeline of late-stage clinical studies that focus on the prevention of VTE in cancer patients. In addition, Quercis targets other diseases associated with thrombotic events, such as sickle cell disease (SCD), Ebola and COVID-19. The Company’s lead drug candidate acts as an antithrombotic with significantly lower risk of adverse events than existing treatments.


Quercis Pharma AG


Quercis Pharma AG

Nordstrass 5
6300 Zug