Bioequivalence and Bioavailability Forum

❝ Is it requrie to perofrm full validation in case of the range is expanded to cover unknown samples. The method is already validated and during the study only it's comes to knwo that the reange is narrow and ULOQ is need to be expand.

• If only a few samples are affected and you have already validated the dilution integrity (see EMA’s draft, Section 4.1.7) only samples above the ULOQ have to be reanalysed.
  
• If dilution integrity was not validated, do it now. Continue as above.
  
• If the entire range is to be ‘stretched’ (many samples above the old ULOQ), perform a partial validation of the new range (accuracy, precision). Consider either adding a higher upper QC sample or keeping only the low QC and adjust the intermediate and upper QC to the new range. IMHO you can only skip storage (short term, long-term, bench-top, stock solution).