Bioequivalence and Bioavailability Forum • Pilot or Two-Stage

Pilot or Two-Stage [Design Issues]

posted by Helmut – Vienna, Austria, 2013-02-18 14:53 (4879 d 00:59 ago) – Posting: # 10049
Views: 8,114

Dear Ken!

❝ Then, how do we estimate the sample size to achieve at least 80% power for BE study on this drug ?

The 30years old paper does not help. After 5mg in five (!) subjects CV_total of C_max 93% and of AUC_t 51%… You need CV_intra from a cross-over study.

IMHO you have two options:

Perform a pilot study which will (after drop-outs) > the minimum sample size in your regulation (Malaysia: 12). State in the protocol that if you are able to show BE already in the pilot the study will act as the pivotal study.
Perform a Two-Stage Sequential Design (see e.g., this presentation). Ask your authority whether such a design is acceptable. The Malaysian GL from 2000 of course does not cover such a design.

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

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Complete thread:

Trifluoperazine Ken Peh 2013-02-16 16:26 [Design Issues]
- Trifluoperazine drgunasakaran1 2013-02-17 08:53
  - Trifluoperazine Ken Peh 2013-02-18 07:28
    - Pilot or Two-StageHelmut 2013-02-18 13:53
      - Pilot or Two-Stage Ken Peh 2013-02-18 18:19
        
        Pilot or Two-Stage Helmut 2013-02-19 13:37
        
        Pilot or Two-Stage Ken Peh 2013-02-20 03:34
        
        Post hoc power & other things… Helmut 2013-02-20 20:11
        
        Post hoc power & other things… Ken Peh 2013-02-22 08:17
        
        Post hoc power & other things… Helmut 2013-02-22 14:15
        
        Post hoc power & other things… Ken Peh 2013-02-24 09:08
        
        estimation ≠ calculation Helmut 2013-02-24 17:09