Pharmacokinetic assay and analysis services for advanced therapy development

Unlike small molecule drugs, gene therapy drugs, mRNA, and RNA therapeutics are not administered as finished products ready to act in the body. Instead, in advanced therapies, the therapeutic agent must be synthesized within the target cell. This fundamental difference means that traditional pharmacokinetics (PK) terminology—covering absorption, distribution, metabolism, and excretion (ADME)—needs to be adapted for gene therapies.

Pharmacokinetics focuses on the distribution, persistence, and clearance of the vector DNA and, potentially, the transgene product. These studies aim to understand how the body processes the vector drug product, where it localizes, and how the transgene is expressed.

A pharmacokinetic assay includes extraction, conversion to cDNA in the RT step (for RNA analytes), quantification using qPCR or dPCR, data normalization, and quality control.

For viral vectors, primary pharmacokinetic analytes include vector DNA, transgene mRNA, and protein. While the therapeutic protein is often the final intended product, its levels may be below detection limits or indistinguishable from endogenous proteins. As a result, transgene mRNA serves as a reliable proxy and is quantified using highly sensitive RT-PCR, followed by qPCR or dPCR for precise measurement.

Our pharmacokinetic services comprises the development of PK assays to ensure accuracy and sensitivity, with method validation guaranteeing assay robustness. The validated assay meets predefined criteria for LLOQ, LOQ, MQC, HQC, and ULOQ, providing reliable and reproducible results. We run preclinical pharmacokinetic analyses and clinical pharmacokinetic analyses.

qPCR and dPCR are highly sensitive methods for detecting low-copy-number nucleic acids and genes in complex genetic backgrounds for pharmacokinetics. With proper assay design, these methods can distinguish between highly homologous sequences.

Short targets such as miRNA, siRNA, and ASOs can be accurately quantified using Two-Tailed PCR technology.

Since every target drug nucleic acid is unique, primer and probe design must be developed and validated for each construct. Extraction efficiency, RT-step performance, and PCR efficacy vary depending on the test item’s length, modifications, and secondary structures.

Compliance with Good Laboratory Practice (GLP) for pharmacokinetic (PK) studies submitted to regulatory agencies ensures data reliability, integrity, and traceability. As a GLP-accredited laboratory, we adhere to a rigorous framework for sample management, controlled work environments, instrument maintenance, temperature regulation, staff training, and IT security. Additionally, we implement time-stamped sample handling to safeguard both sample and data integrity.

Good Clinical Laboratory Practice (GCLP) bridges GLP principles with Good Clinical Practice (GCP) to ensure high-quality, regulatory-compliant bioanalytical data for clinical pharmacokinetic studies.

Our ISO/IEC 17025 accreditation demonstrates technical competence in laboratory testing, ensuring consistent, high-quality results. In pharmacokinetic assessments, ISO compliance enhances credibility, particularly for non-regulated studies and global collaborations, supporting the development and regulatory approval of gene therapies and RNA-based therapeutics.