From: Johan.Rosenborg@astrazeneca.com
Subject: [NMusers] Urinary excretion
Date: Tue, September 28, 2004 3:18 am
All,
I would like to fit a model simultaneously to plasma and urine data on a
substance that is almost exclusively eliminated via the kidneys - the
preliminary estimate using the F0 parameter is 98%.
My problem: urine recovery in some subjects is larger than the actually
administered dose
My question: How should I take into account the mass balance discrepancy?
/ Johan
Urinary excretion
From: "Bachman, William (MYD)" bachmanw@iconus.com
Subject: RE: [NMusers] Urinary excretion
Date: Tue, September 28, 2004 7:36 am
1. You could set these people up as drug factories - might be cheaper than
manufacturing overhead.
2. Incorporate a bioavailability factor, which in this case, would be
greater than one. Then get creative about explaining why it is.
From: Michael.J.Fossler@gsk.com
Subject: RE: [NMusers] Urinary excretion
Date: Tue, September 28, 2004 9:00 am
Our colleagues at Wyeth know a little about getting horses to "manufacture" drugs in this way :^))
Mike
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Michael J. Fossler, Pharm. D., Ph. D., F.C.P.
Principal Clinical Pharmacokineticist
Clinical Pharmacokinetics, Modeling & Simulation
GlaxoSmithKline
(610) 270 - 4797
FAX: (610) 270-5598
Cell: (443) 350-1194
Michael_J_Fossler@gsk.com
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From:"Alice Nichols" NICHOLA2@wyeth.com
Subject: RE: [NMusers] Urinary excretion
Date: Tue, September 28, 2004 10:42 am
Johan,
I would think you could model this as part of the residual error
for urine data since presumably this is due to combination of assay
variability as well as potential inaccuracies in the urine volume measurements.
Alice
Alice I Nichols, PhD
Sr Director, Clinical Parmacology
Wyeth Research
500 Arcola Rd
Collegeville, PA 19426
tel: 484-865-8741/ fax: 484-865-9075
nichola2@wyeth.com
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