Helmut
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Vienna, Austria,
2015-06-08 14:35
(3216 d 21:45 ago)

Posting: # 14925
Views: 8,663
 

 LLOQ/2 for BQLs not suggested [PK / PD]

Dear all,

just found an interesting statement in an EPAR of 2013:

The CHMP raised questions about the appropriateness of calculations using below limit of quanti­ta­tion (BLQ) and exclusion of data. The applicant provided re-evaluated PK parameters and statis­tical analysis not replacing BLQ with the half value of lower limit of quantitation (LLOQ).

(my emphasis)

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d_labes
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Berlin, Germany,
2015-06-08 15:31
(3216 d 20:48 ago)

@ Helmut
Posting: # 14926
Views: 7,221
 

 Zero suggested?

Dear Helmut!

Using 0 (zero) instead for that BLOQ?
Or exclude (the text names exclusion of data)?

Regards,

Detlew
Helmut
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Vienna, Austria,
2015-06-08 16:02
(3216 d 20:18 ago)

@ d_labes
Posting: # 14927
Views: 7,413
 

 Interpolate?

Dear Detlew!

❝ Using 0 (zero) instead for that BLOQ?


Do you remember this thread?

❝ Or exclude (the text names exclusion of data)?


I’m not sure which data were originally presented. From the wording in the EPAR I guess that the applicant set BQLs between two measurable samples to LLOQ/2. Duno what they have done with the first BLQ in the elimination. Some people set this value to LLOQ/2 as well.
  • I would never ever use LLOQ/2 in the elimination.
  • “Embedded BQLs” (© Simon Davis) are a topic of endless debates. Personally I use the lin-up / log-down trapezoidal (which interpolates). Luckily I never saw embedded BQL in my studies for years. ;-)

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ElMaestro
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Denmark,
2015-06-08 16:37
(3216 d 19:42 ago)

@ Helmut
Posting: # 14928
Views: 7,206
 

 Impute?

Haha,

strictly speaking this one still applies, no?

But they forgot that BE trials are confirmatory as well, and that the conservative population in BE is the PP population and not the ITT populaton.

Go ahead, try and claim you are compliant with LOCF :-D

Pass or fail!
ElMaestro
d_labes
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Berlin, Germany,
2015-06-08 16:51
(3216 d 19:28 ago)

@ Helmut
Posting: # 14929
Views: 7,240
 

 "embedded BLOQ" aka "triangular points"

Dear Helmut!

❝ Do you remember this thread?


Yesss Sir.
Oh! That nasty "triangular points" again!

My habit up to now was to take a value of zero for them. Contrary to what ANVISA expects (exclude = identical with interpolate) and what you do (interpolate) if I remember it right from the above mentioned post.

Of course only until tlast.

Regards,

Detlew
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