Steps to consider in pharmacodynamic assay development

1. Reagents
• Identify key reagents
• Coating and Detection Antibody pairs
• Assay Standards
• Standard Matrix and Specimen diluent
• Identify and produce sufficient quantities of suitable assay controls (“Quality Control Specimens”)
• Secure lots of key reagents and formulate “master lot”
• Estimate required dynamic range and analytical sensitivity of the assay
• Develop assay for each specimen type to be used
• Develop/optimize for the number of determinations to be performed per specimen
• Begin collecting data on assay stability:
  • Reagents
  • Specimens
  • Standards and Controls
• Write documents for all aspects of assay
• Test assay on model system (e.g. Xenografts) and human specimens
• Validate assay analytical performance
• Precision
• Accuracy
• Site-to-site reproducibility
• Check validated assay performance on specimens
• Tumor Tissue
• Mouse tumors – in vivo experiments.
• Human tumors
• Determine need of other tumor types and acquire if needed
• Peripheral Blood Mononuclear Cells
• Obtain IRB approval for healthy volunteers and patients and coordinate obtaining samples
• Other potential surrogate tissues


2. Sample Collection and Handling
• Tumor Samples
• Minimum amount of tumor sample required (14-18 gauge syringes)
• Determine optimal time of collection post drug administration(2-4 hours) – in in vivo animal experiments
• Specimen handling and processing
• Specimen stability on freeze/thaw
• Peripheral Blood Mononuclear Cell Samples
• Minimum amount of sample required
• Determine optimal time of collection post drug administration– in in vivo animal experiments
• Specimen handling and processing
• Specimen stability on freeze/thaw
• Other potential surrogate tissues


3. Data Handling and Reporting
• Establish rules to determine validity of an assay
• Establish rules to determine validity of individual specimen results
• Develop report format suitable for use by statisticians and clinicians