Medicine care team

Dr. Bjarnason received his medical degree from the University of Iceland in 1979. He moved to Canada in 1983, completing internal medicine training at Queen's University followed by medical oncology and clinical pharmacology at the University of Toronto.

He has been a medical oncologist at Sunnybrook since 1990 and is currently an associate professor at The University of Toronto and a senior scientist in the Cancer Research Program.

Dr. Bjarnason's basic research has focused on circadian rhythms in human biology and their potential implications for the timing of cancer therapy in the clinic. For the past 20 years, his clinical work and clinical research has focused on patients with kidney cancer.

Education:

• MD, 1979, University of Iceland
• FRCPS(C), 1987, Certification in Internal Medicine, Royal College of Physicians and Surgeons, Canada
• FRCPS(C), 1988, Certification in Medical Oncology, Royal College of Physicians and Surgeons, Canada

Appointments and Affiliations:

• Senior scientist, Biological Sciences, Odette Cancer Research Program, Sunnybrook Research Institute
• Associate professor, faculty of medicine, University of Toronto
• Anna-Liisa Farquharson Chair in Renal Cell Cancer Research

Research Foci:

• Potential clinical applications of chronobiology and chronopharmacology in oncology
• Kidney cancer therapy

Research Summary:

For over 20 years, Dr. Bjarnason has focused his clinical work and research on kidney cancer (renal cell cancer). He was recently appointed the inaugural Anna-Liisa Farquharson Chair in Renal Cell Cancer Research. He is considered one of the leading experts on kidney cancer in Canada and collaborates extensively nationally and internationally on clinical trials and research projects. He works with scientists in biological sciences and physical sciences at Sunnybrook Research Institute, and recently found a method to optimize how anti-angiogenic drugs (drugs that block blood flow to cancer cells) are given to patients with renal cancer.

Dr. Bjarnason's basic and translational research focuses on the potential clinical applications of chronobiology and chronopharmacology in oncology. Most physiological and metabolic processes in the body are ordered in time (that is, they have a circadian rhythm). Therefore, the time of day a drug is delivered may have an impact on how it is handled in the body. Several clinical trials have confirmed that the timing of chemotherapy can have an impact on a drug's side effects profile, and in some cases, improve activity. Based on his data on cell cycle progression in oral mucosa, Dr. Bjarnason has shown that the timing of radiotherapy can have an impact on the severity of oral mucositis in patients with head and neck cancer. 

The new drugs that are being introduced for cancer are aimed at molecular targets (including angiogenesis) that are much more specific than those of conventional chemotherapy. The expression of many of these molecular targets varies significantly through the 24-hour day. Dr. Bjarnason is working to define the 24-hour variation of these new cancer therapy targets at the gene level and protein level in human tissue to allow for the design of intelligent clinical trials to optimize the effect and minimize the toxicity of these drugs. 

When the sleep-activity rhythm is disturbed in animals and humans, cancer grows faster. Dr. Bjarnason has contributed to this important field of research and is conducting clinical trials aimed at normalizing the circadian rhythm in patients.

Selected Publications:

See current publications list at PubMed.

Book chapters (not in PubMed):

1. Kollmannsberger C, Bjarnason GA, Ravaud A. Toxicity management of renal cell cancer patients on targeted therapies. In:
Lara PN, Jonasch E, editors. Kidney cancer: principles and practice. New York: Springer Heidelberg Dordrecht; 2012. p. 265–284.
2. Bjarnason GA, Giacchetti S, Mormont C, Levi F. Aspects cliniques de la chronothérapie du cancer. In: Labrecque G, Sirois-Labrecque M editors. Chronopharmacologie: rythmes biologiques et medicaments. Montreal: Les Presses de l'Université de Montréal; 2002. p. 346–374.
3. Vyzula R, Bjarnason GA, Hrushesky WJM. Chronopharmacology and avoidance of anticancer drug toxicity. In: Sweetenham JW, Williams CJ, editors. Supportive care of the cancer patient. London: Edward Arnold Publishers; 1996. p. 74–86. 
4. Bjarnason GA, Hrushesky WJM. Preclinical trials of cancer chronotherapy. In: Hrushesky WJM, editor. Circadian cancer therapy. Boca Raton: CRC press; 1994. p. 211–239. 
5. Bjarnason GA, Hrushesky WJM. Cancer chronotherapy. In: Hrushesky WJM, editor. Circadian cancer therapy. Boca Raton: CRC press; 1994. p. 241–263.
6. Hrushesky WJM, Bjarnason GA, Vyzula R. Circadian cancer chronotherapy. In: Cvitkovic E, Droz JP, Armand JP, Khoury S, editors. Handbook of chemotherapy in clinical oncology. Jersey: Scientific Communication International Ltd.; 1993. p. 109–119. 

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• Overcoming treatment resistance in cancer: Therapy can simply stop working, to devastating end. New research gets closer to why (SRI Magazine, 2016)
• A tapestry of clinical trials: High-impact findings: greater effectiveness, more precision, less harm and cost-conscious—this is what the cancer care of tomorrow looks like, emerging from the clinical trials of today (SRI Magazine, 2016)
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