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Dear All,
Will any one please help me in solving my problem. I am using
Winnonlin software for the prediction of bid data from single dose
data. How it has to be done and steady state concentration can be
predicted from this. It is reported that drug is following linear
kinetics and i am using non compartmental analysis for the same, but
unable to do the same.
With Regards,
Tushar Nahata
Tushar Nahata
Deptt of Pharmacy
Shri G S Institute of Technology and Science
Indore (MP)
[Have a look at
http://www.boomer.org/c/p4/c14/c1401.html
and
http://www.boomer.org/c/p4/c15/c1501.html
- db]
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The following message was posted to: PharmPK
Dear Dr Nahata,
I'm not clear exactly what you want to achieve/demonstrate in
your analysis. If you are confident your drug is following linear
kinetics then the option "Nonparametric Superposition" wizard under the
Tools menu in WinNonlin. You have two options, regular dosing will
assume steady state is reached at 10 half-lives (which is probably
erring on the cautious side as most people work on 5-7) and give you a
full dosing interval profile on that day.
Or if you use the variable dosing you can specify the period
over which you want to see the output which is nice to see the full
profile over all days and will match some of the Graphs that David
linked to. Either of these tools will give you an output sheet you can
run an NCA on.
Alternatively you could actually fit a compartmental model and
then simulate from that. If you want to hear more about this then
please be aware we have reserved a couple of places at a special rate
for academics at our course next month in India. Please contact Lindsay
Keane (lkeane.-a-.pharsight.com) if you would like to register or find out
more soon as there are only a few places left.
WinNonlin v5.2 Hands-on Training
DATE: December 9-10, 2008
LOCATION: Hyderabad Marriott Hotel and Convention Center, Hyderabad,
India
The objective of this course is to acquaint the attendees with the key
features and functions of WinNonlin, a state of the art software tool
for analysis of PK and PD data. This course emphasizes hands-on
experience, and all software features are learned in the context of
typical problems faced by pharmacokinetic scientists.
**** Pharsight will also be participating in the Bioavailability,
Bioequivalence, Pharmacokinetics & Beyond workshop being held 1-3
December 2008 at The Pride Hotel in Ahmedabad, India. This conference
is sponsored by the Shivrath Centre for Excellence in Clinical Research,
Ahmedabad, India
http://www.pharsight.com/events/events_calendar.php
India is emerging as the fastest growing market for contract research,
predominantly in the area of bioavailability and bioequivalence. This
3-day workshop will provide you with an invaluable opportunity to
exchange experiences through interactive discussions and case studies
presented by the industry's leading professionals, consultants and
academic leaders.
Simon Davis, Senior Scientific Consultant at Pharsight, will be
presenting a talk at this workshop titled Using WinNonlin(r)
AutoPilot(tm) and PKS(tm) to generate TFLs rapidly and effectively in
BA/BE studies.
For more information, please contact the Shivrath Centre for
Excellence in Clinical Research, Ahmedabad, India
Best regards,
Simon.
--
Simon Davis
Senior Scientific Consultant
http://www.linkedin.com/in/simondavis
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Dear Tushar,
Start with opening a workbook which contains a data set for one or
more subjects with subject ID, time (in h), and concentration in
adjacent columns. Subject ID must be filled out for all rows that have
a time and concentration.
Open 'tools' in the Top Bar of WinNonlin and click 'non parametric
superposition'.
Click the tab Variable dosing and fill in 0 for time and fill in the
dose on the first row, then 12 (for BID dosing) and the dose etc.
Continue this till you have reached the time that corresponds to 6 or
7 terminal half-lives of the drug to ensure that you are in SS for
some time.
Let's assume you thalf is 12 hours, then your last line could be time:
72 and the dose.
Then fill in for output time range for instance 132 h, which would be
the total dosing time plus 5 times the half-life, so your output will
show the decline in concentration after the last dose.
Click define terminal phase and fill in the timepoints in your data
set that you wish WinNonlin to use for calculating the half-life which
it uses to superimpose concentrations of each next dose onto the
previous one.
If your data set has values for several subjects, then you can sort by
subject; for time of first dose drag time to that box, and drag
concentration to the box.
For number of output data points, you need to do a bit of
calculating...If your drug has a steep rise with Cmax at for instance
0.5 hours, and you want to see it in the output, then you can decide
on a data point every half hour over the 132 h interval that you have
specified before, so that makes 264 plus 1 for the end of the last
half hour interval. If the original curve is more gradual, you can
decide on one data point every hour, so that would make 133. You can
save your settings, sometimes handy should you wish to do it later on
with a different data set or dose.
Then click Calculate! WinNonlin will produce a wkbk with the estimated
concentrations for the entire 132 h period, and plot them as well.
The tab regular dosing works in a similar way, but I do not like it as
much because it does to show the process of attaining steady state.
Have a go at it, and play with it, for various data sets, it is not
that difficult!
Good luck,
Frieda
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Dear Tushar,
WinNonlin can be used to simulate Multiple Dose (MD) profiles given PK
parameters calculated from Single Dose (SD) data. There is simulate
checkbox in de DATA dialogbox. You should provide data on the regimen
(e.g. BID for x Days) in the dosing submenu/dialog box. for all
profiles you would like to simulate. However, I don't think you can
use use PK parameters calculated bij non compartmental analysis (NCA).
You should try compartmental modeling to calculate the necessary
parameters and then run the simulations (i.e. predictions).
Hope this helps a bit,
Jan Hartstra
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