Bioequivalence and Bioavailability Forum • LLOQ “low enough”?

LLOQ “low enough”? [Bioanalytics]

posted by Helmut – Vienna, Austria, 2013-01-10 21:46 (4521 d 12:14 ago) – Posting: # 9821
Views: 8,063

Hi John,

❝ Do you consider 1ng/mL LLoQ sufficient with the current state of art equipments? I think it's too high (Sciex 5500+ can do better).

Can’t tell. The lowest level one possibly can reach depends on the molecule, ionisation sites, clean-up/trace-enrichment, blah blah. I have seen a validated method for formoterol with an LLOQ of 400 fg/mL already eight years ago. That’s 2500times lower than your 1 ng/mL – but likely another drug, right? :-D

❝ With the drug I am working with, based on pilot data, will be like 120 ng/mL for Cmax (the highest Cmax, the study was 200 mg so assuming 2x200mg). The range now is 1ng/mL - 200 ng/mL. I think I can push down the ULoQ to 100 ng/mL and do dilution for higher conc samples.

Sounds OK, but didn’t you see no values >LLOQ in ~40% of the subjects?

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Helmut Schütz

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Complete thread:

FDA definition of non-accurately and reliably jag009 2013-01-09 22:20
- Experiences with EU submissions Helmut 2013-01-10 14:03
  - Experiences with EU submissions jag009 2013-01-10 16:36
    - Experiences with EU submissions Helmut 2013-01-10 16:56
      - Experiences with EU submissions jag009 2013-01-10 20:07
        
        LLOQ “low enough”?Helmut 2013-01-10 20:46
        
        LLOQ “low enough”? jag009 2013-01-11 15:20
        
        LLOQ “low enough”? Ohlbe 2013-01-11 19:16
        
        LLOQ “low enough”? jag009 2013-01-11 20:14