Bioequivalence and Bioavailability Forum • Sample Size for Drugs Interaction studies

Lara
☆

Mexico,
2015-11-04 00:19
(3463 d 13:07 ago)

Posting: # 15610
Views: 8,026

Sample Size for Drugs Interaction studies [Power / Sample Size]

Hi Helmut,

Question: Is it correct to use BE sample size estimation for Drugs interaction studies? If not, What should we do to estimate the sample size for this type of studies? I want to estimate the sample size for two drugs and their combination (3x3 crossover) and for two drugs, their combination and two drugs together (4x4 crossover) as William's design.

Thanks!

Lara

Edit: Category changed. [Helmut]

d_labes
★★★

Berlin, Germany,
2015-11-04 12:12
(3463 d 01:14 ago)

@ Lara
Posting: # 15611
Views: 6,197

Sample Size for Drugs Interaction studies

Post reply

Dear Lara!

❝ Hi Helmut,

Not interested in the opinion of other forum members? :no:

❝ Question: Is it correct to use BE sample size estimation for Drugs interaction studies?

Some readings:
- Guidances FDA and EMA.
- Book:
STEVEN A. JULIOUS, SAY BENG TAN, DAVID MACHIN
"An Introduction to Statistics in Early Phase Trials"
Chapter 10

After diving into this literature you will detect "It is correct to use BE sample size estimation also for Drugs interaction studies". At least as standard case.
Eventually you have to adapt the BE acceptance range, aka no-effect margin in the context of drug-interaction studies. Quote from the above recommended book: "Depending on the drug(s), a no-effect margin wider (or narrower) than (0.80, 1.25) may be justified ...".
Don't ask me about the justification :-D

—
Regards,

Detlew

Helmut
★★★

Vienna, Austria,
2015-11-04 12:17
(3463 d 01:09 ago)

@ Lara
Posting: # 15612
Views: 6,240

Sample Size for Drugs Interaction studies

Post reply

Hi Lara,

❝ Hi Helmut,

▲ Not interested in opinions of other members of the forum? :-D

❝ Question: Is it correct to use BE sample size estimation for Drugs interaction studies?

Absolutely. A similar statistical model as for BE is applicable.*

H₀: Drug interaction
H₁: Lack of drug interaction

The design of DDI studies is more demanding than the statistics (steady state, different half lives, …).
Search the forum to get some impressions.

Steinijans VW, Hartmann M, Huber R, Radtke HW
Lack of pharmacokinetic interaction as an equivalence problem
Int J Clin Pharm Ther Toxicol 1991;29(8):323–8
PMID 1601534

—
Dif-tor heh smusma 🖖🏼 Довге життя Україна!
Helmut Schütz

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

Lara ☆ Mexico, 2015-11-04 19:28 (3462 d 17:58 ago) (edited on 2015-11-04 22:36) @ Helmut Posting: # 15613 Views: 6,017	Sample Size for Drugs Interaction studies Post reply
	Thank you both, I will check the documents Edit: Full quote removed. Please delete everything from the text of the original poster which is not necessary in understanding your answer; see also this post! [Ohlbe]