Bioequivalence and Bioavailability Forum

Hi all,

As per new health canada guideline, two strategies for collecting data in stages are Group Sequential Designs and Adaptive Designs.

1. Group sequential design - Currently, we are planning to use group sequential design for BE studies. But i having query regarding the sample size (i.e. no. of subjects) used for Stage 1 and Stage 2.

we provide the sample size for stage 1 as per intra cv calculation (i.e. N=60).
My query is
i) do we have to proposed stage 2 sample size in the sample protocol (i.e. N1 + N2) or
ii) after completion of stage 1 analysis we calculate sample size by using stage 1 ISCV (i.e. N= 80)
iii) therefore stage 2 sample size is (N1 + N2 i.e. 60+80 = 140).


Please provide which method to be use for calculation of stage 2 sample size.

Thanks & Regards,

Sandy