Mitochondrial Toxicity

Mitochondrial Toxicity refers to adverse effects on mitochondrial structure or function caused by drugs or metabolites, leading to impaired energy production, oxidative stress, altered apoptosis signalling, and cellular injury. Because mitochondria generate ATP through oxidative phosphorylation and regulate metabolic homeostasis, mitochondrial dysfunction can result in clinically significant toxicity affecting high-energy tissues including liver, heart, skeletal muscle, and nervous system.

The pharmaceutical industry prioritises early detection and mitigation of mitochondrial toxicity due to its association with severe clinical outcomes and late-stage development failures. Preclinical screening includes assays measuring mitochondrial membrane potential, oxygen consumption rate, ATP depletion, reactive oxygen species production, and mitochondrial DNA content in relevant cell models. Certain drug classes including some antivirals and antibiotics have historically demonstrated mitochondrial liabilities, prompting improved predictive testing and medicinal chemistry strategies to reduce risk. Clinical monitoring may include liver function tests, lactate measurements, muscle symptoms, or cardiotoxicity signals. Regulatory submissions require comprehensive safety evaluation when mitochondrial effects are suspected. As mechanistic understanding improves and screening platforms become more predictive, mitochondrial toxicity assessment remains a core component of safety pharmacology.