Bioequivalence and Bioavailability Forum 01:43 CET

Main page Policy/Terms of Use Abbreviations Latest Posts

 Log in |  Register |  Search

Sundar.M
Junior

India,
2018-09-27 11:11

Posting: # 19330
Views: 665
 

 RSABE - Sequence [RSABE / ABEL]

Dear all,

What would be the advantages/disadvantages of following 6 sequences (TRR, RTR, RRT, RTT, TRT and TTR) in a RSABE design, instead of 3 sequences as per FDA recommendations. Your comments are highly appreciated.


Thanks
Sundar. M
Helmut
Hero
avatar
Homepage
Vienna, Austria,
2018-09-28 13:15

@ Sundar.M
Posting: # 19337
Views: 554
 

 Suggested: TRT|RTR

Hi Sundar,

» […] advantages/disadvantages of following 6 sequences (TRR, RTR, RRT, RTT, TRT and TTR) in a RSABE design, instead of 3 sequences as per FDA recommendations.

Advantages
  • Additionally to the estimate of CVwR you get the one of CVwT (good to know esp. if your study is a pilot and you want to design a pivotal study where CVwR ≠ CVwT). In the partial replicate you have to assume that CVwR = CVwT.
  • If swR <0.294 (only ABE acceptable) no convergence issues in the mixed-effects model with the FDA’s covariance-specification.
Disadvantages
  • Sample size is a multiple of six (instead of three in the partial replicate and two in the three-period full replicate).
  • Design currently not implemented in PowerTOST’s function sampleN.RSABE().
If you want to kill two birds with one stone I recommend the three-period two-sequence full replicate design (TRT | RTR) instead.

Cheers,
Helmut Schütz
[image]

The quality of responses received is directly proportional to the quality of the question asked. ☼
Science Quotes
Sundar.M
Junior

India,
2018-09-28 13:36

@ Helmut
Posting: # 19338
Views: 540
 

 Suggested: TRT|RTR

Thank you HS!
Activity
 Thread view
Bioequivalence and Bioavailability Forum |  Admin contact
19,154 posts in 4,080 threads, 1,308 registered users;
online 8 (0 registered, 8 guests [including 5 identified bots]).

One can show the following: given any rule, however “fundamental”
or “necessary” for science, there are always circumstances
when it is advisable not only to ignore the rule,
but to adopt its opposite.    Paul Feyerabend

The BIOEQUIVALENCE / BIOAVAILABILITY FORUM is hosted by
BEBAC Ing. Helmut Schütz
HTML5 RSS Feed