Back to the Top
Please suggest, if a pilot BE study is underpowered (45%) but T/R
ratio is approx 102% with intrasubject variability is more that 45%
would it be correct to derive decision that it is not formulation
effect but study is poorly controlled. Based on this data can we go
ahead for pivotal study with more number of subject.
Regards
Anuj Saini
Back to the Top
The following message was posted to: PharmPK
Hi Anuj,
You probably can go ahead to design the pivotal study. You may not even
need to call the 1st study as poorly controlled since it was a pilot
study and it sounds you probably have got the information you needed
from it (T/R delta/ratio and hopefully inter-sub variability in addition
to intra-sub variability as you mentioned below) to design the pivotal
study.
Jinshan
Back to the Top
The following message was posted to: PharmPK
Hi Anuj,
Just another thought - depending on your study design and power
calculation, it might be conservative/prudent to assume a little bigger
T/R delta than 0.02 for the pivotal study, although this may change the
location of the stiff portion of the power curve.
Regards,
Jinshan
Back to the Top
The following message was posted to: PharmPK
How is in vitro data looks like. If dissolution profile is similar,
then it is ok to prceed with pivotal with more number of subjects.
Masood Bhatti
BioPharma Services
Torontol
Back to the Top
The following message was posted to: PharmPK
Dear Anuj,
Ideally the pilot study should be designed to obtain sufficient
predictive information for the Pivotal Biostudy. Please check the
whether you have the intrasubject CV close to the reported. If the T/
R ratios and 90% C. I are very much with in 80-125% then only a
increase (almost double of the pilot study) in sample size would be
advisable. You must also look into the factors which may have
contributed to such a large variability eliminate them in your
Pivotal study to have better control.
Regards
Manojkv
Back to the Top
Dear Anuj,
If we see then practically it is not happening very rarely.
Just check the p value in ANOVA of formulation effect and go ahead
with more sample size, your formulation is well developed.
regards.....
Want to post a follow-up message on this topic?
If this link does not work with your browser send a follow-up message to PharmPK@boomer.org with "Underpowered BE study" as the subject | Support PharmPK by using the |
Copyright 1995-2011 David W. A. Bourne (david@boomer.org)