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Developmental and Reproductive Toxicity Testing Strategies for Oligonucleotides: A Workshop Proceedings
Bethany R Hannas1, Sara M Bender2, Eileen Blasi3
1Eli Lilly & Company, Indianapolis, Indiana, USA.
Abstract:
A 2023 workshop brought together stakeholders involved in the development and safety assessment of oligonucleotide (ONT) therapeutics. The purpose was to discuss potential strategies and opportunities for enhancing developmental and reproductive toxicity (DART) assessment of ONTs. The workshop was timely, bringing together regulators, industry representatives, consultants, and contract research organization partners interested in the ongoing development of internationally harmonized guidance for nonclinical safety assessment of ONTs. Given DART's importance in nonclinical safety assessment and the unique attributes of ONTs, the forum discussed case studies, consensus approaches, and areas needing further development to optimize DART strategies. This report covers the workshop proceedings, highlighting methods to achieve a robust DART assessment for ONTs. It includes case studies that described strategies for dose level selection, dosing frequency, species selection, and alternative animal model approaches. Topics also cover surrogate ONT use, exposure of the placenta and embryo/fetal compartment, and weight of evidence approaches. A goal of these workshop proceedings is to describe example approaches to hopefully inform the DART strategy expectations in the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidance currently under development for nonclinical safety assessment of ONTs.
Insights
This workshop focused on improving developmental and reproductive toxicity (DART) assessments for oligonucleotide (ONT) therapeutics. Key strategies discussed aim to harmonize global guidance for safer drug development.
Area of Science:
- Pharmacology and Toxicology
- Drug Development
- Regulatory Science
Background:
- Oligonucleotide (ONT) therapeutics represent a rapidly advancing class of drugs.
- Robust safety assessment, particularly developmental and reproductive toxicity (DART), is crucial for ONT approval.
- Existing DART assessment strategies may require adaptation for unique ONT properties.
Purpose of the Study:
- To convene stakeholders to discuss and identify strategies for enhancing DART assessments of ONTs.
- To foster consensus on best practices and address knowledge gaps in ONT DART evaluation.
- To inform the development of harmonized international guidance for ONT safety assessment.
Main Methods:
- A workshop format brought together regulators, industry experts, consultants, and contract research organizations.
- Discussions included case studies, consensus-building on approaches, and identification of areas for further research.
- Review of strategies for dose selection, dosing frequency, species selection, and alternative models.
Main Results:
- Exploration of surrogate ONT use and assessment of exposure in placental and embryo/fetal compartments.
- Discussion of weight-of-evidence approaches for comprehensive DART evaluation.
- Identification of specific methods and case studies to optimize DART strategies for ONTs.
Conclusions:
- The workshop provided valuable insights into optimizing DART strategies for oligonucleotide therapeutics.
- The proceedings aim to guide the development of harmonized international regulatory expectations for ONT safety.
- Collaborative efforts are essential for establishing robust and efficient DART assessments in this field.
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