Sriraj
☆    

India,
2010-02-26 15:23
(5949 d 03:31 ago)

Posting: # 4825
Views: 8,278
 

 BA/BE [Design Issues]

Dear all,

Please help me regarding the following:

Difference between Bioavailability and Bioequivalence studies – not the definitions. Answeres required - Regarding the study conduct, analysis, sample size estimation, 90% CI etc.,

Thanks in advance,
SriKanth *SriRaj*
Helmut
★★★
avatar
Homepage
Vienna, Austria,
2010-02-26 18:10
(5949 d 00:44 ago)

@ Sriraj
Posting: # 4828
Views: 7,433
 

 Difference between BA and BE

Dear SriKanth!

For basics of bioequivalence see this post. For planing, conduct, evaluation, etc. see my lectures.

BE studies are always confirmatory (i.e., you want to demonstrate something with given alpha- and beta-errors), whereas BA studies are exploratory (i.e., the results are descriptive only).
Since in BA we don't test a statistical hypothesis, sample size generally is based on rules-by-thumb. Most regulations require a minimum of 12 subjects, but 24-36 are commonly used. Results are generally reported as geometric means (AUC, Cmax), median (tmax) together with their 95 % confidence intervals. In BA we are interested in understandig the drug/formulation, therefore the entire arsenal of PK-metrics may be applied (MRT, Cmax/AUC, :blahblah:).
There is a fuzzy border between simple BA- and more complex PK-studies. Whereas the former will be evaluated by NCA-methods only, the latter may call for classical PK-modeling, physiology-based PK and/or population PK.

Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz
[image]

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes
Sriraj
☆    

India,
2010-03-01 06:29
(5946 d 12:24 ago)

(edited on 2010-03-01 11:52)
@ Helmut
Posting: # 4836
Views: 7,102
 

 Difference between BA and BE

Dear Helmut,

Nice to see reply from you, I was also thinking the same, thanks for the confirmation. My understanding is that, in BA and BE the presentation of the results would be same but the interpretation is different, I mean in BA studies we evaluate geometric ratio and 90% CI from the same model as we do for BE studies but in BA we say that no hypothesis is involved hence there wont be any power as well.

Could you please also answer to my posting #4826 Sample Size BA/BE.

Many thanks,
SriKanth


Edit: Full quote removed. Please delete anything from the text of the original poster which is not necessary in understanding your answer; see also this post! [Jaime]
Helmut
★★★
avatar
Homepage
Vienna, Austria,
2010-03-01 14:52
(5946 d 04:02 ago)

@ Sriraj
Posting: # 4839
Views: 7,102
 

 Second try

Dear SriKanth!

❝ [...] in BA studies we evaluate geometric ratio and 90% CI


I did not say that. In BA you should report 95 % confidence intervals.

❝ [...] but in BA we say that no hypothesis is involved hence there wont be

❝ any power as well.


Yes.

❝ Could you please also answer to my posting #4826 Sample Size BA/BE.


Since there are no hypotheses to test - no power, no sample size calculation; it's up to you. Please read my previous post again.

Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz
[image]

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes
UA Flag
Activity
 Admin contact
23,653 posts in 4,991 threads, 1,570 registered users;
135 visitors (0 registered, 135 guests [including 36 identified bots]).
Forum time: 19:54 CEST (Europe/Vienna)

There are no dangerous thoughts;
thinking itself is dangerous.    Hannah Arendt

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz
HTML5