Brad Urquhart

Brad Urquhart

Associate Professor

PH.D. University of Western Ontario
B.Sc. University of Western Ontario
Office:  Dental Science Building, Room 2011C
p. 519.661.2111 x. 83756
f. 519.661.3827
See Publications by Brad Urquhart on PubMed

The focus of my laboratory is studying the mechanisms responsible for variation of response to medications in the setting of kidney disease.

It is estimated that there are currently 2 million Canadians who either have or are at high risk of developing kidney disease. Approximately 35,000 Canadians are currently on renal replacement therapy (i.e. dialysis) and this number is expected to double over the next 10 years. Patients with chronic kidney disease require several prescription medications to control co-morbidities such as diabetes, hypertension and various types of infection. In fact, dialysis patients often receive 6-12 medications concurrently.

Although the effect of kidney failure on the renal excretion of drugs is well documented, emerging evidence suggests that absorption, distribution and metabolism of many drugs are significantly altered leading to variable pharmacokinetics and efficacy. The objective of my laboratory is to gain a better understanding of the processes that govern the response to drugs in kidney failure. In particular, we study the activity and regulation of drug metabolizing enzymes and drug transport proteins in the setting of kidney failure. The vision of the lab is to use molecular biology combined with clinical investigation in order to appreciate both the mechanistic basis for variable drug response along with providing useful clinical data to optimize drug therapy in patients.


Down-regulation of hepatic CYP3A and CYP2C mediated metabolism in rats with moderate chronic kidney disease. Velenosi TJ, Fu AY, Luo S, Wang H, Urquhart BL. Drug Metabolism and Disposition (2012)40(8):1508-1514

Intestinal CYP3A4 and midazolam disposition in vivo associate with VDR polymorphisms and show seasonal variation. Thirumaran RK, Lamba JK, Kim RB, Urquhart BL, Gregor JC, Chande N, Fan Y, Qi A, Cheng C, Thummel KE, Hall SD, Schuetz EG. Biochemical Pharmacology (2012)84(1)104-112.

Disposition of atorvastatin, rosuvastatin and simvastatin in oatp1b2-/- mice and intraindividual variability in human subjects. Degorter MK, Urquhart BL, Gradhand U, Tirona RG, Kim RB. Journal of Clinical Pharmacology (2012)52(11):1689-1697.

In vitro and in vivo assessment of renal drug transporters in the disposition of mesna and dimesna. Cutler MJ, Urquhart BL, Velenosi TJ, Meyer zu Schwabedissen HE, Dresser GK, Leake BF, Tirona RG, Kim RB, Freeman DJ. Journal of Clinical Pharmacology (2012)52(4)530-542.

Human skeletal muscle drug transporters determine local exposure and toxicity of statins. Knauer MJ, Urquhart BL, Meyer zu Schwabedissen HE, Schwarz UI, Lemke CJ, Leake BF, Kim RB, Tirona RG. Circulation Research (2010)106(2)297-306.

Breast cancer resistance protein (ABCG2) and drug disposition: intestinal expression, polymorphisms and sulfasalazine as an in vivo probe. Urquhart BL, Ware JA, Tirona RG, Ho RH, Leake BF, Schwarz UI, Zaher H, Palandra J, Gregor JC, Dresser GK, Kim RB. Pharmacogenetics and Genomics (2008)18(5):439-448.

Mesna for treatment of hyperhomocysteinemia in hemodialysis patients:a placebo-controlled, double-blind, randomized trial. Urquhart BL, Freeman DJ, Cutler MJ, Mainra R, Spence JD, House AA. Clinical Journal of the American Society of Nephrology (2008)3(4):1041-1047.

The effect of mesna on plasma total homocysteine concentration in hemodialysis concentration. Urquhart BL, Freeman DJ, Spence JD, House AA. American Journal of Kidney Diseases (2007)49(1):109-117.