The clinical success of therapeutic oligonucleotides, including siRNAs, ASOs, and mRNA, is fundamentally tied to their absorption, distribution, metabolism, and excretion (ADME) properties. Unlike traditional small molecules, these large, polyanionic molecules exhibit unique pharmacokinetic (PK) profiles characterized by rapid plasma clearance and extensive tissue distribution, primarily governed by their chemical modifications and delivery vehicles. CD BioGlyco provides an end-to-end ADME profiling service tailored specifically for the nuances of oligonucleotide drugs. Our platform integrates high-sensitivity bioanalysis with sophisticated metabolic mapping to resolve the fate of your drug in vivo. By leveraging a "platform-based" approach, we help clients navigate the transition from lead optimization to regulatory submission, ensuring that every modification to the phosphorothioate backbone or GalNAc cluster is accounted for in terms of exposure and safety.
To address the analytical challenges posed by complex biological matrices, we utilize a suite of high-resolution technologies:
This dual-mode approach combines the specificity of hybridization (using a complementary PNA or DNA probe) with the mass resolution of LC-MS/MS. It allows for the simultaneous quantification of the parent drug and its truncated metabolites (e.g., n-1, n-2 fragments) with sub-nanogram sensitivity.
For a truly comprehensive view of distribution, we utilize radiolabeled (3H, 14C, or 33P) oligonucleotides. QWBA provides high-resolution imaging of drug localization across all tissues, including difficult-to-reach compartments like the CNS or bone marrow.
We employ ultra-sensitive ELISA for high-throughput PK screening. These assays are ideal for measuring total drug concentrations in plasma during early-phase dose-ranging studies.
Using sandwich-cultured hepatocytes and recombinant transporter models, we assess the interaction of GalNAc-conjugated oligos with hepatic efflux and renal uptake transporters (OAT1/3), providing critical data for drug-drug interaction (DDI) risk assessment.
Our ADME profiling service is comprehensive, covering a diverse array of therapeutic modalities including ASOs, siRNAs, miRNAs, aptamers, and mRNA payloads. We offer cross-species analysis (mouse, rat, rabbit, NHP, human) to facilitate translational scaling. Our scope extends to specialized delivery systems, such as GalNAc-conjugated oligos and LNP-encapsulated RNAs, where we track both the targeting ligand and the nucleic acid payload. Additionally, we provide "deep tissue" profiling, which includes subcellular fractionation to determine the concentration of the drug that has successfully escaped the endosome and entered the cytoplasm or nucleus.
Our team of ADME specialists provides strategic guidance by conducting an in-depth analysis of your oligonucleotide's unique sequence and chemical modification pattern (e.g., 2'-OMe, LNA, PS backbone). We leverage this analysis to design a bespoke, hypothesis-driven ADME study program. This includes selecting the most pharmacologically relevant animal models and proactively identifying potential metabolic "hotspots" or stability liabilities, thereby building a robust and efficient investigation plan from the outset.
We develop, optimize, and fully validate sensitive and specific bioanalytical assays tailored to your unique molecule and its anticipated metabolites. This critical step involves the optimization of complex extraction and purification protocols from challenging biological matrices, such as the liver, kidney, and brain, to ensure maximum analyte recovery while effectively minimizing matrix interferences, thereby guaranteeing reliable quantification throughout the study.
We employ a multi-modal approach to precisely track your drug's journey from the administration site to its final destination. Using quantitative whole-body autoradiography (QWBA) for spatial visualization and highly sensitive tissue-homogenate LC-MS/MS for absolute quantification, we characterize the detailed kinetics of drug accumulation, persistence, and clearance in both target and off-target tissues, providing a complete picture of biodistribution.
Samples from in vitro and in vivo studies are analyzed using high-resolution mass spectrometry to elucidate the primary metabolic pathways of your oligonucleotide. We map the precise cleavage sites susceptible to endo- and exonucleases, and structurally characterize the resulting metabolites. This enables us to assess whether any metabolites retain biological activity or have the potential to contribute to off-target effects, informing both efficacy and safety profiles.
We conduct rigorous radiolabeled or cold mass balance studies to determine the routes and extent of elimination (renal vs. biliary/fecal). Achieving a complete mass balance is essential to confirm that no significant unknown metabolites are accumulating in the body, thereby addressing a key safety requirement for clinical translation.
All generated pharmacokinetic, metabolism, and excretion data are integrated into advanced physiologically based pharmacokinetic (PBPK) models. These models are used to simulate and project human PK profiles and safety margins.
Journal: Nucleic Acid Therapeutics
DOI: 10.1089/nat.2023.0011
IF: 4.7
Published: 2023
Results: This white paper from the oligonucleotide safety working group (OSWG) provides comprehensive recommendations for the nonclinical pharmacokinetic and ADME characterization of therapeutic oligonucleotides, including ASOs and siRNAs. The authors systematically outline a science-based framework for study design, timing, and data interpretation, drawing parallels to but also highlighting key distinctions from small molecule drug assessments. A central proposal is the adoption of a platform-based approach, where established data for a specific oligonucleotide class (e.g., a particular chemistry or conjugate like GalNAc) can support the development of subsequent compounds within that same platform, thereby reducing redundant testing. The document details specific considerations for various study types, including single- and repeat-dose pharmacokinetics, tissue distribution, plasma protein binding, in vitro drug-drug interactions, and metabolite safety testing, while addressing unique aspects of conjugated, formulated, and locally administered oligonucleotides. The overarching goal is to offer sponsors and regulatory bodies a consensus-driven, practical guide to ensure robust and efficient nonclinical evaluation, enhancing the predictability of human outcomes and supporting the clinical translation of this promising class of therapeutics.
Hepatic RNAi Therapeutics
Profile the liver-specific accumulation and ASGPR-mediated uptake of GalNAc-siRNA conjugates, ensuring that the payload is effectively delivered to hepatocytes to silence targets like PCSK9 or ANGPTL3 with minimal systemic impact.
Neurodegenerative Disease Programs
Assess the PK of intrathecally administered ASOs, quantifying the half-life of the drug in the CSF and its distribution into deep brain structures like the striatum and cortex for treating Huntington's or ALS.
Ocular Oligonucleotide Delivery
Track the persistence and metabolic stability of intravitreally injected oligonucleotides, ensuring that therapeutic concentrations are maintained in the retina over extended periods to treat macular degeneration or inherited retinal diseases.
Renal-Targeted ASO Development
Quantify the high renal accumulation typical of oligonucleotides and monitor the metabolic fate of the drug in the kidney, providing essential data for assessing potential nephrotoxicity and ensuring long-term safety.
Hybridization LC-MS/MS Excellence
Our platform overcomes the sensitivity limits of traditional LC-MS by utilizing hybridization capture. This allows us to quantify oligonucleotides at sub-nanogram levels in difficult tissues like the brain or bone marrow, providing a clear picture of exposure.
Platform-Based Predictive Modeling
By leveraging our extensive database of chemical modifications, we can often predict the PK behavior of new candidates. This platform approach significantly accelerates the lead optimization process and reduces the need for redundant animal testing.
High-Recovery Tissue Extraction
We have developed proprietary lysis and extraction protocols that ensure maximum recovery of oligonucleotides from highly protein-bound matrices. This ensures that the reported drug concentrations are an accurate reflection of the total tissue burden.
Endosomal Escape Quantification
Potency is often limited by endosomal entrapment rather than total tissue concentration. Our specialized assays quantify the "biologically available" drug within the cytosol, providing a much more relevant metric for potency than bulk tissue levels alone.
CD BioGlyco provided the most detailed MetID report we've ever seen. Their ability to pinpoint the exact nuclease cleavage sites allowed us to redesign our lead ASO for 3x greater stability.
— By Dr. T.R., Head of Pharmacokinetics
The hybridization-capture LC-MS platform at CD BioGlyco is a game-changer. They reached a sensitivity level in brain tissue that our previous CRO simply couldn't achieve.
— By Manager, DMPK
We rely on CD BioGlyco for all our NHP pharmacokinetic studies. Their data is consistently high-quality, and their understanding of oligonucleotide chemistry is unmatched in the industry.
— By Director, Bioanalysis
mRNA Biodistribution Analysis Service
High-resolution tracking of mRNA localization and LNP carrier fate.
T Cell Cytokine Secretion Analysis Service
Monitoring the systemic immune response to RNA therapeutics for safety profiling.
Antibody Titer and Specificity Analysis Service
Comprehensive assessment of the humoral response to therapeutic payloads.
Neutralizing Antibody Assay Service
Detecting antibodies that may compromise the efficacy of long-term oligonucleotide treatment.
CD BioGlyco is dedicated to providing the scientific clarity required to bring next-generation RNA therapeutics to the clinic. Our ADME profiling service combines deep bioanalytical expertise with state-of-the-art technology to resolve the most complex pharmacokinetic challenges. Whether you are navigating lead optimization or preparing for a global regulatory filing, contact us!
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