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The following message was posted to: PharmPK
I would like to do analysis of dissolution test with Win Nolin. I would
like to know the better fit for several different dissolution profile.
I
wonder if somebody have already employed this program in this task, and
if
is there any library of models for WinNonlin for dissolution test
profiling.
Thanks in advance
Benjamin Santos Ph.D.
Pharmacokinetics and Metabolism Dept.
Ferrer Internacional S.A.
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Hi,
we have used more than 16 models for in vitro dissolution data (both
mechanistical and empirical models). All of these with both Kinetica
and WNL.
What kind of data do you have? There is a dissolution profile of an
immediate release dosage form (you need empirical models) or of a
modified release dosage form (mechanistical)?
If you need empirical models, try Hill (works very good), Weibull (the
same) - there are 2 Wb models, Logistic (2 models), Morgan, ...
For mechanistical models, there are: release by 0, 1st order kinetics,
Peppas (semiempirical), Hopfenberg (1,2,3), Hixson-Crowel, Higuchi.
Usually,
is better
to use complex kinetic models, for example models including at least 2
parallel or consecutive kinetic processes (e.g. 1st order and 0 order).
These models can be built taking account on how you have prepared the
pharmaceutical form (e.g. matrix, reservoir...)
Regards,
vlase
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The following message was posted to: PharmPK
Dear Benjamin,
You might want to consider our DDDPlus(TM) ("Dose Disintegration and
Dissolution Plus") program, which will be released shortly after about
two years in development.
DDDPlus is a full simulation of in vitro dissolution, including particle
size distributions, excipient and API dissolution prediction/fitting,
continuous calculation of ionic balance, and effects of experiment fluid
volume, instrument speed, initial pH, selected buffers and surfactants.
It provides Parameter Sensitivity Analysis as well as the ability to fit
models to observed dissolution data.
Best regards,
Walt Woltosz
Chairman & CEO
Simulations Plus, Inc. (AMEX: SLP)
1220 W. Avenue J
Lancaster, CA 93534-2902
U.S.A.
http://www.simulations-plus.com
Phone: (661) 723-7723
FAX: (661) 723-5524
E-mail: walt.aaa.simulations-plus.com
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Dear Dr. Santos,
There are several compiled models available in WinNonlin which could be
used for dissolution analysis, depending upon the dissolution profile.
For example, if your profile indicates that saturating conditions are
reached, you could fit one of the Emax models (simple or sigmoid) and
use your dissolved drug as the Y variable with time as the X variable.
Alternatively, if the dissolution process is first order, you could
consider fitting a compartmental PK model to the undissolved drug data
(obtained from Total - dissolved).
Analysis of your data using other models including the Makoid-Banakar
equation is also possible, but would require writing a user-defined
model.
With Best Regards,
Christopher Mehl
Software Support Engineer
support.at.pharsight.com
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