Skin Sensitisation Defined Approach ITSv1

The Skin Sensitisation Defined Approach ITSv1, offered by Lhasa Limited, is an in silico software solution designed to predict the hazard and potency of chemicals with respect to skin sensitisation, serving as a robust alternative to animal testing. It is built on Next Generation Risk Assessment (NGRA) principles and employs New Approach Methodologies (NAMs), making it suitable for professionals working in cosmetics, personal care, pharmaceuticals, occupational safety, extractables and leachables, and REACH registrations.

Lhasa's skin sensitisation assessment suite comprises three complementary tools — Derek Nexus, Vitic, and the Skin Sensitisation Defined Approach ITSv1 — each addressing different aspects of dermal sensitisation evaluation. Together, they support regulatory-compliant, non-animal safety assessments across a wide range of industries and use cases.

Derek Nexus Capabilities

• Contains well-established Structure-Activity Relationship (SAR) knowledge to assess skin sensitisation hazard and potency of chemicals.
• Provides EC3 predictions to extrapolate hazard identification to risk, enabling potency assessment.
• Negative predictions allow confident classification of compounds as non-sensitisers when no skin sensitisation alerts are triggered.
• High Potency Category (HPC) alerts identify structural features associated with extreme skin sensitisation potential in the Local Lymph Node Assay (LLNA), informing the selection of appropriate Dermal Sensitisation Thresholds (DSTs).
• Can be used as part of a defined approach in combination with in vitro and in chemico assays, including those outside the applicability domain of existing non-animal assays.
• Specifically recommended by OECD Guideline No. 497 as the in silico component within the ITS defined approach, supporting a robust weight-of-evidence assessment of dermal sensitisation.

Vitic Capabilities

• Provides high-quality, peer-reviewed skin sensitisation data to support individual safety assessments and read-across approaches.
• Offers access to both in vivo skin sensitisation data and data from New Approach Methodologies, including in chemico and in vitro assays.
• Regularly updated with new data, enabling users to access current information to support predictions and read-across assessments.
• Contains expert-curated data from both published and unpublished sources, ensuring high data quality and reliability.

Skin Sensitisation Defined Approach ITSv1 Capabilities

• Delivers hazard and potency skin sensitisation predictions in place of animal tests, assisting hazard characterisation and risk assessment.
• Implements the OECD Guideline No. 497 defined approach (DA) by combining a Derek Nexus prediction with h-CLAT and DPRA data to quickly and efficiently predict hazard and potency categories.
• Demonstrated to have a comparable or higher level of accuracy than traditional animal models when predicting human outcomes.
• Automates the Data Integration Procedure (DIP) through a web application that considers applicability domains, handles missing information sources, and assesses prediction confidence.

Regulatory Support

• REACH: Derek Nexus, Vitic, and ITSv1 provide alternative methods to in vivo animal studies, in line with REACH provisions that animal testing should be a last resort.
• CLP Regulation: The tools provide skin sensitisation predictions that can be used for chemical safety assessment and correct hazard classification, labelling, and packaging of substances and mixtures.
• OECD Guideline No. 497: The ITSv1 tool directly supports this guideline's defined approaches for skin sensitisation, advancing the 3Rs principle — replacement, reduction, and refinement of animal use in testing.
• EU Regulation 1223/2009: Supports compliance with the prohibition on animal testing for cosmetic ingredients; Derek Nexus used within a Defined Approach delivers predictions with high concordance with the LLNA assay.
• ICH Q3E: Derek Nexus can be used to predict the sensitisation potential of extractables and leachables (E&L) compounds, in preparation for the upcoming ICH Q3E guideline requirements.

The Skin Sensitisation Defined Approach ITSv1 and its companion tools are delivered as software solutions by Lhasa Limited, supporting use cases spanning occupational exposure, cosmetic ingredient safety, pharmaceutical extractables and leachables, and REACH registrations, all within a framework aligned with current and emerging international regulatory guidelines.