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RegisterNew guidance on Statistical Approaches to Establishing Bioequivalence [BE/BA News]
Dear All
The FDA Generic Drugs Advisory Committee recommended in 1991 that the primary comparison of interest in a BE study is the ratio, rather than the difference, between average PK parameter data from the T and R formulations. Using logarithmic transformation, the general linear statistical model employed in the analysis of BE data allows inferences about the difference between the two means on the log scale, which can then be retransformed into inferences about the ratio of the two averages (geometric means) on the original scale. Logarithmic transformation thus achieves a general comparison based on the ratio rather than the differences.
Under lognormal data for PK paramertes ratio of geometric means the same as ratio of medians
However, situations with different within-subject variances of drugs may often occur in practice. BE tests cannot be easily transformed back from the log scale to the original scale under unequal within-subject variances.
The FDA Generic Drugs Advisory Committee recommended in 1991 that the primary comparison of interest in a BE study is the ratio, rather than the difference, between average PK parameter data from the T and R formulations. Using logarithmic transformation, the general linear statistical model employed in the analysis of BE data allows inferences about the difference between the two means on the log scale, which can then be retransformed into inferences about the ratio of the two averages (geometric means) on the original scale. Logarithmic transformation thus achieves a general comparison based on the ratio rather than the differences.
Under lognormal data for PK paramertes ratio of geometric means the same as ratio of medians
However, situations with different within-subject variances of drugs may often occur in practice. BE tests cannot be easily transformed back from the log scale to the original scale under unequal within-subject variances.
Complete thread:
- New guidance on Statistical Approaches to Establishing Bioequivalence Relaxation 2022-12-02 15:53 [BE/BA News]
![[Mix]](https://static.bebac.at/img/mix.png "open in Mix view")
- A first look Helmut 2022-12-02 16:43
- A first look jag009 2022-12-02 17:58
- A first look BRB 2022-12-02 18:20
- SAS strikes back mittyri 2022-12-02 20:38
- SAS strikes back Helmut 2022-12-02 22:30
- Outliers? mittyri 2022-12-02 22:52
- Outliers? Helmut 2022-12-02 23:11
- SAS strikes back Achievwin 2023-02-07 07:23
- Outliers? mittyri 2022-12-02 22:52
- SAS strikes back Helmut 2022-12-02 22:30
- model-based BE? mittyri 2022-12-07 16:26
- model-based BE? Helmut 2022-12-10 10:13
- Hooker, Moellenhoff et al. are moving MBBE forward mittyri 2023-01-11 15:32
- model-based BE? SMA 2023-01-17 09:41
- model-based BE? Helmut 2022-12-10 10:13
- A first look PharmCat 2022-12-21 19:30
- A first look Rayhope 2023-01-06 06:56
- A first look jag009 2022-12-02 17:58
- Groups, sites… Helmut 2022-12-03 13:09
- SxF ElMaestro 2022-12-04 06:34
- SxF Helmut 2022-12-10 10:37
- New guidance on Statistical Approaches to Establishing BioequivalenceMahmoud 2022-12-10 14:08
- Webinar: A Deep Dive: FDA Draft Guidance on Statistical Approaches to Establishing Bioequivalence SMA 2023-02-06 09:07
- Webinar: A Deep Dive: FDA Draft Guidance on Statistical Approaches to Establishing Bioequivalence Achievwin 2023-02-07 07:13
- Multi-group studies ad nauseam Helmut 2023-02-07 11:30
- Multi-group studies ad nauseam Achievwin 2023-02-25 16:18
- Webinar: Recording available Helmut 2023-04-01 10:38
- Multi-group studies ad nauseam Helmut 2023-02-07 11:30
- Speed kills Helmut 2023-02-07 13:02
- Webinar: A Deep Dive: FDA Draft Guidance on Statistical Approaches to Establishing Bioequivalence Achievwin 2023-02-07 07:13
- A first look Helmut 2022-12-02 16:43
Ing. Helmut Schütz