# BLQ handling in BE study where all values in one profile are BLQ

**URL:** <https://forum.certara.com/t/blq-handling-in-be-study-where-all-values-in-one-profile-are-blq/3456>\
**Category:** Phoenix WNL basics\
**Created:** [November 28, 2019, 12:39pm UTC](https://forum.certara.com/t/blq-handling-in-be-study-where-all-values-in-one-profile-are-blq/3456 "2019-11-28T12:39:46Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![simon.hutchings](https://avatars.discourse-cdn.com/v4/letter/s/a88e4f/32.png) [@simon.hutchings](https://forum.certara.com/u/simon.hutchings)\
**Post date:** [November 28, 2019, 12:39pm UTC](https://forum.certara.com/t/blq-handling-in-be-study-where-all-values-in-one-profile-are-blq/3456/1 "2019-11-28T12:39:46Z")

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_\<Apologies if this is not in the correct subforum - I could not find a ‘regulatory’ option!\>_

I am analyzing a ‘simple’ 2 way cross bioequivalence study of a generic oral capsule.

Our standard approach for BE studies is to replace BLQs with zero.

However, one subject has a profile for test product where all values are BLQ; their reference product profile is relatively in line with the rest of the dataset. If this was the other way around (reference profile all BLQ) the EMA BE guidelines would allow exclusion from the analysis; alas we are not in that position.

There are no other clinical/medical reasons to exclude this subject from the PK analysis set, however the zero values for Cmax and AUC cannot be log transformed and therefore this subject’s data cannot included in the statistical analysis.

My initial thought would be to replace BLQ with half LLOQ for this subject only.

Does that seem like a logical solution? Very grateful for anyone’s thoughts/experiences from a regulatory acceptability perspective.

Simon

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**Author:** ![SimonDavis](https://avatars.discourse-cdn.com/v4/letter/s/d9b06d/32.png) [@SimonDavis](https://forum.certara.com/u/SimonDavis)\
**Post date:** [November 28, 2019, 12:47pm UTC](https://forum.certara.com/t/blq-handling-in-be-study-where-all-values-in-one-profile-are-blq/3456/2 "2019-11-28T12:47:56Z")

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This is a tricky one, are you familiar with the BEBAC forum, you may get more guidance on regulatory experiences there;

[https://forum.bebac.at/mix\_entry.php?id=7701&page=0](https://forum.bebac.at/mix_entry.php?id=7701&page=0)

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**Author:** ![simon.hutchings](https://avatars.discourse-cdn.com/v4/letter/s/a88e4f/32.png) [@simon.hutchings](https://forum.certara.com/u/simon.hutchings)\
**Post date:** [November 28, 2019, 12:58pm UTC](https://forum.certara.com/t/blq-handling-in-be-study-where-all-values-in-one-profile-are-blq/3456/3 "2019-11-28T12:58:34Z")

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> [@sdavis](#):
>
> This is a tricky one, are you familiar with the BEBAC forum, you may get more guidance on regulatory experiences there;
> 
> [https://forum.bebac.at/mix\_entry.php?id=7701&page=0](https://forum.bebac.at/mix_entry.php?id=7701&page=0)

Thank you Simon - I was not aware of the BEBAC forum, I’ll try there!