Published in Bioanalysis
The 13th GCC Closed Forum for Bioanalysis was held in New Orleans, Louisiana, USA on April 5th, 2019. This GCC meeting was organized to discuss the contents of the 2019 ICH M10 Bioanalytical Method Validation Draft Guideline published in February 2019 and consolidate the feedback of the GCC members. In attendance were 63 senior-level participants f...
Published in Bioanalysis
Internal standards (ISs) are essential for the development and use of reliable quantitative bioanalytical LC-MS/MS methods, because they correct for fluctuations in the analytical response that are caused by variations in experimental conditions. Sample-to-sample differences in the IS response are thus to be expected, but a large variability often ...
Published in Bioanalysis
Internal standard (IS) response has been an active topic of discussion within the bioanalytical community. Initial discussions focused on developing criteria for anomalous responses. Recently, understanding the cause and potential impact of variable IS response has been emphasized. Following a review of recommendations from industry discussions reg...
Published in Bioanalysis
Aim: Monitoring the internal standard (IS) response is common practice in bioanalysis by LC-MS/MS. IS response variation may raise questions on assay quality and should trigger investigations into the root cause. Results: In two case studies with IS variability, re-analysis of diluted samples and spiking predose study samples revealed no effect of ...
Published in Bioanalysis
Published in Bioanalysis
The guidelines for immunogenicity studies by the European Medicines Agency and the US FDA are based on different legislations and regulatory philosophies. In spite of the different background, the main guidelines are compatible on the scientific level, especially for new innovative therapeutic protein products. The importance of sensitive and drug-...
Published in Bioanalysis
Internal standards are essential to ensure the reliability of chromatographic bioanalytical methods. However, this only holds true if the response of the internal standard is adequately monitored. A difference needs to be made between isolated variations in a limited number of samples, which can be easily handled using objective criteria triggering...
Published in Bioanalysis
Published in Bioanalysis
Two case studies are presented of validated assays where the internal standard showed high variability, and there was a clear response difference between study samples and standards and quality controls. In the first case a co-eluting peak boosted the stable isotope labeled internal standard response in samples from hepatically impaired subjects. I...
Published in Bioanalysis
Internal standard response is routinely monitored in regulated studies to accept or reject individual samples with outlier results due to potential sample processing or instrumentation errors, and processes are typically governed by standard operating procedures. However, acceptance or rejection of individual samples is not always sufficient. Inter...
