FDA Guidance for Biodistribution Studies in Gene Therapy
The longer the GT product persists, the greater the duration and degree of risk of delayed adverse events. FDA recommends the clinical biodistribution studies using methods shown to be sensitive and quantitative to detect product sequences. These studies should be designed to determine the distribution of the product in non-target tissues and the persistence of the product in both non-target and target tissues following direct in vivo administration of the product.
The studies should employ an animal species that permits vector transduction and/or vector replication and that the animal species be biologically responsive to the specific transgene of interest or to therapeutic components in the product (e.g., for products that may not contain transgenes and only genome editing components).
Digital Droplet PCR (ddPCR) Platforms for Viral Biodistribution Studies
QX200 AutoDG Droplet Digital PCR System
Quantstudio 3D Digital PCR System
Stilla ddPCR
Fludigm Biomark System
Quantstudio 3D Digital PCR System
Stilla ddPCR
Fludigm Biomark System
Advantages of digital PCR
- Nanoliter droplet partitioning - reduces bias from amplification efficiency differences and PCR inhibitors
- Convenient assay design - standard curves are not required
- Ability to increase precision by using more PCR replicates
- High tolerance to inhibitors
- Capability to analyze complex mixtures
- Linear detection of small-fold changes
- Multiplexing
ddPCR Platforms
QX200/QX100 AutoDG Droplet Digital PCR System
The QX200 AutoDG Droplet Digital PCR System provides absolute quantification of target DNA or RNA molecules for EvaGreen and probe-based Droplet Digital PCR (ddPCR) applications. The Automated Droplet Generator simplifies the ddPCR workflow, making digital PCR both scalable and practical.- Please visit the product webpage for further information
Quantstudio 3D Digital PCR System
- Please visit the product webpage for further information
Stilla ddPCR
- Please visit the product webpage for further information
Fludigm Biomark System
- delivers unparalleled accuracy and real-time digital PCR capabilities.
- the capability to quantitate up to two targets per sample using multiple dyes
- Please visit the product webpage for further information
Other Application of Droplet Digital PCR
Next-Generation Sequencing Library Quantification- Absolute quantification of NGS libraries and validation of sequencing results, without reference standards.Rare Mutation Analysis- Detect and quantify rare mutations for low-prevalence targets in cancer research samples.
Differential Gene Expression- Detect gene expression changes of ±10% for absolute transcript quantification without a reference gene.
Viral Load Quantification- Absolute quantification of bacterial and viral loads, and absolute pathogen counts.
Low-Level Pathogen Detection- Detect low-level pathogens that cause human illnesses through contaminated food and water supplies