Preclinical or nonclinical evaluation is an integral part of the development of any drug. The process of developing a new radiopharmaceutical includes rigorous testing before it can be cleared for use in humans. There must be in-depth characterization of its behaviour to assess its safety and suitability for the intended clinical application. This publication provides a baseline guide for preclinical evaluation of radiopharmaceuticals that will give its readers a general review of the requirements of a facility and insight into the various scientific activities that constitute this process. The principles and protocols discussed herein will provide guidelines for biological assessment of candidate compounds, which are consistent with the principles of good laboratory practices to generate valid nonclinical scientific data towards approval for clinical translation. This publication is intended not only for researchers engaged in radiopharmaceutical development, but also for the Member States planning to set up or upgrade facilities for radiopharmaceuticals’ research.

• 1. INTRODUCTION
  • 1.1. Background
  • 1.2. Objectives
  • 1.3. Scope
  • 1.4. Structure
• 2. GENERAL CONSIDERATIONS OF RADIOPHARMACEUTICAL DEVELOPMENT: PRECLINICAL ASPECTS
  • 2.1. Radiopharmaceutical design and development
    • 2.1.1. Preclinical evaluation of novel radiopharmaceuticals
    • 2.1.2. Pharmacology
    • 2.1.3. Imaging/biodistribution
    • 2.1.4. Toxicology
  • 2.2. Applications for drug development
    • 2.2.1. Preclinical studies using well established radiopharmaceuticals
    • 2.2.2. Preclinical studies using a radiolabelled drug candidate
  • 2.3. Differences among species
  • 2.4. Quality criteria of radiopharmaceuticals for preclinical research
• 3. IN VITRO TESTING
  • 3.1. Study design
    • 3.1.1. Binding studies
    • 3.1.2. Internalization and intracellular/subcellular distribution studies
    • 3.1.3. Cell uptake studies
    • 3.1.4. Dissociation studies
    • 3.1.5. Blocking studies
    • 3.1.6. Efficacy/functional assays
    • 3.1.7. Efflux pump assays and blood brain barrier permeability tests
    • 3.1.8. In vitro autoradiography
    • 3.1.9. Metabolite analysis
    • 3.1.10. Radiopharmaceutical stability during storage
    • 3.1.11. Serum stability
  • 3.2. Selection of adequate cell lines for in vitro assays
  • 3.3. Selection of tissues for tissue based assays
  • 3.4. Environmental considerations
  • 3.5. General remarks on in vitro methods
• 4. IN VIVO AND EX VIVO TESTING
  • 4.1. General principles
    • 4.1.1. Ethical considerations
  • 4.2. Study design
    • 4.2.1. Design and data analysis considerations
  • 4.3. Animal related factors
    • 4.3.1. Animal models
    • 4.3.2. Number of animals and randomization
    • 4.3.3. Administration and sampling
    • 4.3.4. Circadian rhythm
    • 4.3.5. Physiological monitoring
    • 4.3.6. Fasting
    • 4.3.7. Anaesthesia
    • 4.3.8. Euthanasia
    • 4.3.9. Housing conditions and biosafety
  • 4.4. In vivo imaging studies
    • 4.4.1. Characteristics of preclinical PET and SPECT scanners
    • 4.4.2. Image acquisition protocols
    • 4.4.3. Dynamic versus static imaging
    • 4.4.4. Image reconstruction
    • 4.4.5. Correction factors for PET
    • 4.4.6. Correction factors for SPECT
    • 4.4.7. Image data analysis
  • 4.5. Ex vivo testing
    • 4.5.1. Organ biodistribution
    • 4.5.2. Autoradiography
    • 4.5.3. Radiometabolite analysis
    • 4.5.4. Plasma protein binding
  • 4.6. Efficacy studies
• 5. TOXICOLOGY
  • 5.1. Rationale and general principles
  • 5.2. Existing guidelines and recommendations
  • 5.3. Guidance on therapeutic radiopharmaceuticals
  • 5.4. Calculation of human equivalent dose
• 6. DOSIMETRY
  • 6.1. Study design
    • 6.1.1. MIRD principle for dosimetry calculations
    • 6.1.2. Pharmacokinetic modelling of in vivo data to derive time–activity curves
    • 6.1.3. Biodistribution data organ concentrations
    • 6.1.4. Quantitative data of small animal SPECT/PET imaging
    • 6.1.5. Phantoms and models for small animal dosimetry
    • 6.1.6. Voxel based dosimetry models
    • 6.1.7. Small scale dosimetry models
    • 6.1.8. Extrapolation of animal dosimetry to human dosimetry
• 7. DATA REPORTING AND MANAGEMENT
  • 7.1. Data reporting
  • 7.2. Data management
    • 7.2.1. Study and animal identification
    • 7.2.2. Data tracking
    • 7.2.3. Archiving
    • 7.2.4. Data retrieval
• 8. FACILITIES REQUIREMENT
  • 8.1. Facility design
  • 8.2. Equipment
  • 8.3. Staffing requirements
  • 8.4. Staff training
  • 8.5. Safety considerations
    • 8.5.1. Biosafety
    • 8.5.2. Radiation safety
    • 8.5.3. Animal safety
  • 8.6. Accreditation
    • 8.6.1. External review
    • 8.6.2. Good laboratory practice
    • 8.6.3. Association for Assessment and Accreditation of Laboratory Animal Care International
• 9. QUALITY ASSURANCE AND QUALITY CONTROL
  • 9.1. Quality assurance and quality control for laboratory and equipment
    • 9.1.1. Balances
    • 9.1.2. Pipettes
    • 9.1.3. Dose calibrators
    • 9.1.4. Well counters
    • 9.1.5. Gamma counters
    • 9.1.6. Phosphor imagers
    • 9.1.7. Chromatography systems
    • 9.1.8. Laminar airflow hoods
    • 9.1.9. Incubators
    • 9.1.10. Cryostats and microtomes
  • 9.2. Quality assurance and quality control for preclinical imaging scanners
    • 9.2.1. Quality assurance and quality control for PET scanners
    • 9.2.2. Quality assurance and quality control for SPECT scanners
• 10. PROTOCOLS
  • 10.1. In vitro evaluation protocols
    • 10.1.1. Protocol for cell uptake assay
    • 10.1.2. Protocol for saturation binding assay
    • 10.1.3. Protocol for competitive binding assay
    • 10.1.4. Protocol for retention/dissociation assay
    • 10.1.5. Protocol for internalization assay
    • 10.1.6. Protocol for tracer stability assay
    • 10.1.7. Protocol for plasma/serum stability assay
    • 10.1.8. Protocol for in vivo stability assay
    • 10.1.9. Protocol for ex vivo autoradiography
    • 10.1.10. Protocol for γ counter calibration
  • 10.2. In vivo evaluation protocols
    • 10.2.1. In vivo preclinical imaging study with [18F]FDG considerations for different applications
    • 10.2.2. In vivo preclinical imaging
    • 10.2.3. In vivo testing — efficacy of therapeutic radiopharmaceutical
• 11. CONCLUSION
• REFERENCES
• ABBREVIATIONS
• CONTRIBUTORS TO DRAFTING AND REVIEW