In June 2024, the FDA published the final version of the guideline titled “Clinical Pharmacology Considerations for the Development of Oligonucleotide Therapeutics Guidance for Industry”. This document replaces the draft from 2022 and provides recommendations to assist the industry in the development of oligonucleotide therapeutics, but it also poses new challenges for developers and manufacturers.

Previously, Maria Fauth, Nucleic Acids Department Manager at Kymos, shared her experience implementing the draft guideline back in 2022, and now our team has revised this final version and prepared a summary of the most critical aspects and our experience on them.

Oligonucleotide Therapeutics and the New Guideline

Oligonucleotide therapies modulate gene expression to treat a specific condition or pathology by RNase H-mediated cleavage targeted degradation, splicing modulation, non-coding RNA inhibition, gene activation, and programmed gene editing (1). The development of Oligonucleotide Therapies has been arising in the latest years and these therapies and novel drugs include Antisense Oligonucleotides (ASO), siRNA, anti-miRs or antagomirs (anti-miRNA oligonucleotides), Aptamers, Clustered regularly interspaced palindromic repeats (CRISPR) and chemically modified oligonucleotides (1,2)

Since early 2020, different oligonucleotide therapies have been approved by the FDA. Nonetheless, the broad use of these therapies has encountered some challenges, being the most significant ones: the achievement of an efficient delivery to target tissue besides the liver and having some interactions and toxicity (1,3).

Luckily the FDA has recently released the final version of the Guideline for Oligonucleotide Therapeutics, highlighting the following considerations in the development of these new therapies:

  1. Characterizing QTc Interval Prolongation and Proarrhythmic Potential (evaluated by the clinical site)
  2. Performing Immunogenicity Risk Assessments
  3. Characterizing the Impact of Hepatic and Renal Impairment on Pharmacokinetics, pharmacodynamics and Safety.
  4. Considerations of Assessing Drug-Drug Interactions.

Kymos Group Experience with Nucleic Acids

Kymos Nucleic Acid Department has wide experience in the Bioanalysis of different Nucleic Acids and Oligonucleotide Therapies, even pioneering miRNA bioanalysis quantification since 2016. Our department, led by Maria Fauth, has expertise in developing methods from scratch, and above all they have been implementing FDA guidelines in the GLP-compliant validation of our analytical methods since the draft release in 2022, always keeping track of any latest updates of the FDA.

Based on these current Guidelines Considerations and using state-of-the-art technology, Kymos is able to provide expertise in:

  • Immunogenicity assessment:

As mentioned in the Guideline unwanted immune response can be generated by Oligonucleotide Therapeutics due to different reasons, that must be considered during the manufacturing process and tested following a risk-based approach and be included in a product-specific immunogenicity risk assessment as described in the FDA guidance Immunogenicity Assessment for Therapeutic Protein Products (August 2014).

The clinical assessment of immunogenicity for oligonucleotide therapeutics usually includes the FDA’s multi-tiered approach that Kymos has been following throughout the years, as stated in the FDA guidance Immunogenicity Testing of Therapeutic Protein Products — Developing and Validating Assays for Anti-Drug Antibody Detection (February 2019). Kymos can determine Binding ADAs as well as Neutralizing ADAs, by using Electrochemiluminescence (ECLA- MSD®) and Cell-Based Assays.

Additionally, the new FDA guideline mentions that unwanted innate immune activation should also be measured when appropriate, for example, innate immune activation should be measured including oligonucleotide therapeutic-induced cytokine release. By using Multi-plex MSD® and Luminex® technology, Kymos is able to detect several cytokines and biomarkers simultaneously in the same sample, reducing time, cost, and valuable sample amount.

  • Biodistribution and Pharmacokinetics:

As mentioned before, Oligonucleotide Therapies delivery to target tissue as well as liver accumulation is a major challenge. Kymos may assist in providing GLP-compliant results of drug distribution and pharmacokinetics. Our Nucleic Acid department has performed several Biodistribution, Shedding, and Gene Expression determinations by qPCR and RT-qPCR. We are proficient in developing methods in different and complex matrices. We provide Pharmacokinetic Calculation and Statistics using Phoenix WinNonlin® software 8.2 gold standard.

  • Assessing Drug-Drug Interactions:

Oligonucleotide therapeutics are primarily metabolized by nucleases and do not rely on cytochrome P450 (CYP) enzymes. Thus, their pharmacokinetics are not significantly affected by CYP enzyme inducers or inhibitors. Potential drug-drug interactions of oligonucleotide therapeutics inducing or inhibiting CYP enzymes or transporters are evaluated in the early drug development in vitro. Oligonucleotide therapeutics generally show minimal impact on CYP enzymes. Nevertheless, specific assessments may be needed based on chemical modifications and delivery types. At this stage, Kymos can support the CYP induction and inhibition evaluation by Enzyme Activity Assays and on the mRNA expression level.

Conclusions

Oligonucleotide Therapies field has been growing in the past years, rapidly becoming a promising treatment for several complex pathologies. These advanced treatments are being developed and manufactured constantly nowadays and therefore regulatory agencies are providing such guidance to warrant efficacy and safety for the public.

Kymos will be glad to join and assist you throughout your oligonucleotide treatment development pipeline. We are proud to be updated on the implementation of the latest guide provided by the FDA related to Oligonucleotide Therapies and be able to place in your hands our expertise in the required determinations.

If you need more information about these advancements or any assistance with your nucleic acids projects, please contact commercial@kymos.com. We will be pleased to provide you with detailed consulting and support.

Bibliography

  1. Roberts, T; Langer, R and Wood, M. Advances in oligonucleotide drug delivery. (2020). Nature Reviews Drug Discovery volume 19, pages 673–694 (https://www.nature.com/articles/s41573-020-0075-7)
  2. Krützfeldt, J. et al. (2005) Silencing of microRNAs in vivo with antagomirs’. Nature 438, 685–689.
  3. Gagliardi, M and Ashizawa, A.T. (2021). The Challenges and Strategies of Antisense Oligonucleotide Drug Delivery. Biomedicines 16;9(4):433. doi: 3390/biomedicines9040433 (https://pmc.ncbi.nlm.nih.gov/articles/PMC8072990/)