Biomaterial Database

Michaelis-Menten kinetics determine cyclosporine steady-state concentrations: a population analysis in kidney transplant patients. 1993

J Grevel, and B K Post, and B D Kahan

Department of Surgery, University of Texas Medical School.

Dosage adjustments of cyclosporine are confounded with an unexpected degree of variability, thus invalidating a direct proportionality between the oral dose rate and the steady-state concentration. In 1033 observations of dose rate and average steady-state concentration collected during therapeutic monitoring (area under the curve method) in 134 adult kidney transplant patients, a population pharmacokinetic analysis showed that a Michaelis-Menten model fitted the data better than a linear clearance model. It was further shown that the Michaelis-Menten constant (Km) parameter of the Michaelis-Menten model (the average steady-state concentration at half-maximal dose rate) increased during the first 4 months after transplantation whereas the maximal dose rate of the Michaelis-Menten model (Vmax) remained constant. The following parameters with interindividual variation in parenthesis were estimated: Vmax = 852 mg/24 hr (43%) and Km at 114 days after transplantation = 349 ng/ml (117%). An algorithm was derived from this population model that guides the clinician during the adjustment of oral cyclosporine dose rates.

UI	MeSH Term	Description	Entries
D008657	Metabolic Clearance Rate	Volume of biological fluid completely cleared of drug metabolites as measured in unit time. Elimination occurs as a result of metabolic processes in the kidney, liver, saliva, sweat, intestine, heart, brain, or other site.	Total Body Clearance Rate,Clearance Rate, Metabolic,Clearance Rates, Metabolic,Metabolic Clearance Rates,Rate, Metabolic Clearance,Rates, Metabolic Clearance
D011159	Population Surveillance	Ongoing scrutiny of a population (general population, study population, target population, etc.), generally using methods distinguished by their practicability, uniformity, and frequently their rapidity, rather than by complete accuracy.	Surveillance, Population
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D015233	Models, Statistical	Statistical formulations or analyses which, when applied to data and found to fit the data, are then used to verify the assumptions and parameters used in the analysis. Examples of statistical models are the linear model, binomial model, polynomial model, two-parameter model, etc.	Probabilistic Models,Statistical Models,Two-Parameter Models,Model, Statistical,Models, Binomial,Models, Polynomial,Statistical Model,Binomial Model,Binomial Models,Model, Binomial,Model, Polynomial,Model, Probabilistic,Model, Two-Parameter,Models, Probabilistic,Models, Two-Parameter,Polynomial Model,Polynomial Models,Probabilistic Model,Two Parameter Models,Two-Parameter Model
D016030	Kidney Transplantation	The transference of a kidney from one human or animal to another.	Grafting, Kidney,Renal Transplantation,Transplantation, Kidney,Transplantation, Renal,Kidney Grafting,Kidney Transplantations,Renal Transplantations,Transplantations, Kidney,Transplantations, Renal
D016572	Cyclosporine	A cyclic undecapeptide from an extract of soil fungi. It is a powerful immunosupressant with a specific action on T-lymphocytes. It is used for the prophylaxis of graft rejection in organ and tissue transplantation. (From Martindale, The Extra Pharmacopoeia, 30th ed).	Cyclosporin A,Ciclosporin,CsA-Neoral,CyA-NOF,Cyclosporin,Cyclosporine A,Neoral,OL 27-400,Sandimmun,Sandimmun Neoral,Sandimmune,CsA Neoral,CsANeoral,CyA NOF,OL 27 400,OL 27400