February 7, 2025 – A groundbreaking study published in CPT: Pharmacometrics & Systems Pharmacology has used advanced modeling and simulation techniques to analyze acetaminophen (APAP) overdose pharmacokinetics and hepatotoxicity. Researchers compared immediate-release (APAP-IR) and extended-release (APAP-ER) formulations using the quantitative systems toxicology (QST) platform DILIsym, helping to address concerns about potential treatment differences between the two formulations.

Key Findings

The study, conducted by researchers at Simulations Plus Inc. and Kenvue Inc., simulated various acute overdose and repeated supratherapeutic ingestion (RSTI) scenarios to compare APAP-IR and APAP-ER. The results demonstrated that:

• APAP-ER does not significantly alter the pharmacokinetics (PK) compared to APAP-IR, despite its dual-layer structure.

• Hepatic biomarker responses (ALT, total bilirubin, and INR) were nearly identical between the two formulations in overdose scenarios.

• APAP absorption was slightly lower for the extended-release formulation, but this did not meaningfully impact toxicity outcomes.

• No additional risk of delayed toxicity was identified for APAP-ER compared to APAP-IR.

Impact on Clinical Practice

This study supports current APAP overdose treatment guidelines, reinforcing that APAP-ER overdoses should be managed similarly to APAP-IR using the Rumack–Matthew nomogram. The updated 2023 consensus guidelines on acetaminophen poisoning, which recommend a second plasma APAP concentration measurement in some cases, are not further impacted by these findings.

Advancing Toxicology Research

By integrating physiologically based pharmacokinetic (PBPK) modeling and systems toxicology, this research highlights the power of in silico approaches in drug safety assessment. The use of DILIsym, a predictive toxicology tool, enables toxicologists to simulate worst-case overdose scenarios without real-world risk, advancing precision in clinical decision-making.

This study is a significant step in toxicology research, providing reassurance to healthcare providers that APAP-ER overdose cases can be safely managed using existing protocols.

For full details, read the study: DOI: 10.1002/psp4.13304