Singlicate Gyrolab immunoassays prove their worth (again)
In a previous post, ‘How to get it right first time’, we looked at the reliability and reproducibility of Gyrolab™ assays that lead to the idea of running singlicates instead of duplicates (Clark et al, 2016). This publication inspired Hao Jiang and colleagues in a group based at Bristol-Myers Squibb in Princeton, USA to apply Gyrolab technology to run assays of their monoclonal antibody in singlicate in a clinical study. They were encouraged by the results.
Three Gyrolab assays, from discovery to the clinical stage
The team at Bristol-Myers Squibb developed three Gyrolab assays to measure their therapeutic human IgG1 monoclonal antibody, BMS-986207, thus ensuring method continuity through three development stages: discovery (PK/TK) and GLP-toxicology, both run in Cynomolgus monkey, and the clinical phase. A very thorough analysis of assay performance and validation according to current guidelines indicated that all three assays met all acceptance criteria.
Clinical assay performance
The team was encouraged by the performance of the Gyrolab assays. For example, the quantification range of the clinical assay, 150–50,000 ng/mL, would minimize sample dilution and maximize operational efficiency. The total error, bias, and coefficient of variation for this assay were 6.1 – 19.7%, -0.3 – 3.3%, and 3.5 – 18.2%, respectively. The assay was linear up to a dilution of 1:5000. Selectivity and specificity were high, with no anti-drug antibody interference up to 100 ng/mL and no drug interference of administered nivolumab at physiological levels. Carryover was eliminated using Gyrolab Wash Buffer pH 11.
Negligible risk and significant benefit
Based on early experience with the reliability and reproducibility of Gyrolab assays, the team developed and validated the clinical assay such that standards and matrix blanks were run in duplicate, i.e. on separate columns in the CD, from the same sample, whereas the QCs and study samples were run in singlicate.
The rationale for this cost-effective and efficient approach was as follows. The QC criteria still adhered to the 4-6-x rule, whereby four of the six QCs and at least one QC at each level (low, medium and high) must meet the assay criteria of %bias within ±20%. The variation between the duplicates for the standards would be a good indicator of injection accuracy, with inter-column precision being very high (≤ 20% CV 99.5% of the time). Also, the team felt that this approach was valid since during development and validation less than 0.5% of measurements failed due to aberrant inter-column CV%.
The authors concluded by stating, “In the fast-paced world of drug development where ’speed to patient’ is key, we believe that this approach bears negligible risk and can significantly increase benefit to the physicians and patients.”
As we concluded in the previous article, even though you may still be skeptical about using singlicates, reports such as this one confirm that Gyrolab assays clearly deliver data you can depend on.
Find out more
Find out more about how Gyrolab assays can consistently deliver high precision and accuracy in Host Cell Protein (HCP) analysis and pharmacokinetics
Feasibility of Singlet Analysis for Ligand Binding Assays: a Retrospective Examination of Data Generated Using the Gyrolab Platform. Clark, TH et al. AAPS J. 2016 Jul 11. [Epub ahead of print] http://www.ncbi.nlm.nih.gov/pubmed/27401185
Singlicate Ligand Binding Assay Using an Automated Microfluidic System: a Clinical Case Study. Jiang, H et al. AAPS J. 2017 Jun 6. doi: 10.1208/s12248-017-0105-5. [Epub ahead of print] http://www.ncbi.nlm.nih.gov/pubmed/28589510