Back to the Top
The following message was posted to: PharmPK
What would be considered a "common" duration of sampling for BE
determination (ANDA) for an immediate release capsule of a rapidly
absorbed
drug with a half-life of about 1.2 hours (low variability).
I know that the FDA guidance says that sampling (12 to 18 samples)
should
proceed for 3 or more half-lives.
In this particular case, samples in a BE study were carried out to 8
hours
post dosing.
In most all cases at least 3 samples were obtained during the presumed
terminal log-linear phase (total of 15 samples after dosing, 6 in the
first
hour). All samples at 8 hours were 2 or more times the lower limit of
assay
quantitation. Early exposure was well described by the early samples.
I don't doubt that the PK parameters are adequately described by the
data
given this duration of sampling, but it seems to me that even for a drug
with a short half-life such as this one, that it would be more "common"
to
extend out the sampling to 12 or more hours (or more likely it has just
been
a while since I have looked at a BE study for a short half-life drug
and my
memory is failing me :-).
Thanks for any commentary.
Peter U
Back to the Top
The following message was posted to: PharmPK
Peter,
From your description, it sounds like your drug may be a BCS Class I, in
which case you might be able to avoid a BE trial altogether (by showing
that it meets the requirements for Class I).
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.-at-.simulations-plus.com
PharmPK Discussion List Archive Index page
Copyright 1995-2010 David W. A. Bourne (david@boomer.org)