SS indication for dataset with BID dose and AM dose different from PM dose.

4 messages 4 people Latest: Jul 11, 2006
From: "Stuyckens, Kim [PRDBE]" KSTUYCK1@PRDBE.JNJ.COM Subject: [NMusers] SS indication for dataset with BID dose and AM dose different from PM dose. Date: Tue, 11 Jul 2006 17:46:43 +0200 Dear Colleagues, I have a flexible dosing BID study where the AM dose is different from PM dose. At the time PK samples are collected, we are at the steady state condition. Is there anyone familiar with the use of SS and II in this situation? If so, could you show me how SS and II would be implemented in the dataset (please use the example I put below)? In the example below we know that the AM dose is 0.5 and PM dose is 0.8 for more than 10 days (SS is reached after 5 days for this compound) ID DV AMT DATE TIME SS II 1 0 0.8 01/01/2006 20:00 1 0 0.5 01/02/2006 08:00 1 15 0 01/01/2006 08:01 Thanks in advance for the input. Kind regards, Kim
From: "Bill Bachman" Subject: RE: [NMusers] SS indication for dataset with BID dose and AM dose different from PM dose. Date: Tue, 11 Jul 2006 12:12:20 -0400 I think that all you are missing is the ss=1 and ii=24 for lines 1 and 2 (0 for both on line 3). Like anything else you get for free, test it to be sure it does what you expect. (I am hedging because, I have done this with ADDL before, but not SS. Looks like it would work.) J
From: Mark Sale - Next Level Solutions mark@nextlevelsolns.com Subject: RE: [NMusers] SS indication for dataset with BID dose and AM dose different from PM dose. Date: Tue, 11 Jul 2006 09:31:01 -0700 Kim, This is pretty easy (which is the only reason I know the answer). You give two doses, with different doses, as you have, each with II = 24. The only issue is that you have to use a value of 2 for the second SS dose. Normally (SS = 1), it basically erases all previous doses, and uses only and infinite series of doses (backwards not forwards), So, the first dose (probably) has SS=1, erasing all previous doses, and the second has SS=2, giving this dose, on top of the previous dose. But, you will also have to put them in chronological order. (or is the date on the DV record of 1/1/2006 incorrect - it is before the first dose?) ID DV AMT DATE TIME SS II 1 15 0 01/01/2006 08:01 . . 1 0 0.8 01/01/2006 20:00 1 24 1 0 0.5 01/02/2006 08:00 2 24 SS labels PREDPP's steady-state (SS) data item. The steady-state data item is optional. It can take one of three values in any event record. 0 indicates that the dose is not a steady state dose. 1 indicates that the dose is a steady state dose, and that the com- partment amounts are to be reset to the steady-state amounts resulting from the given dose. Compartment amounts resulting from prior dose event records are "zeroed out," and infusions in progress or pending additional doses are cancelled. The system is not totally reset: the on/off status of the compartments remains as it was at the time of the prior event record (if any), and the value of time must be greater than or equal to its value on the prior event record (if any). 2 indicates that the dose is a steady state dose and that the com- partment amounts are to be set to the sum of the steady-state amounts resulting from the given dose plus whatever those amounts would have been at the event time were the steady-state dose not given. I.e., letting t be the time on the event record, then the amounts in the compartments are updated to amounts valid for time t, and next, these amounts are added to the steady-state amounts. This is meaningful when kinetics are linear and the superposition principle holds. Mark Sale MD Next Level Solutions, LLC www.NextLevelSolns.com
From: Paul Hutson prhutson@pharmacy.wisc.edu Subject: RE: [NMusers] SS indication for dataset with BID dose and AM dose different from PM dose. Date: Tue, 11 Jul 2006 13:36:17 -0500 Mark: Like Bill, I have only used ADDL in the past. I would expect, though, to set up SS before the non-zero DV, and then to add doses if needed for subsequent DV values. Do I understand correctly then, that the infinite number of prior doses inferred by SS=1 or =2 is understood when preceding DV items are evaluated? Thanks for your insight. Paul -- Paul R. Hutson, Pharm.D. Associate Professor UW School of Pharmacy 777 Highland Avenue Madison WI 53705-2222 Tel 608.263.2496 Fax 608.265.5421 Pager 608.265.7000, p7856 _______________________________________________________