Current trends in in silico, in vitro toxicology, and safety biomarkers in early drug development.

The development of new medicines is a long and expensive process. Despite growing efforts in R&D over the last decades, attrition rate due to safety issues (especially cardiac and hepatic toxicity) remains a major challenge for the pharmaceutical industry. This may lead to market withdrawal or late stage halting of a drug development program. Consequently, early detection of toxicity issues is critical to avoid late-stage failures. To this end, development of predictive toxicology assays and models have become a strategic matter for drug makers. An integrated approach confronting knowledge-based data sources with in vitro and in vivo experimental data should be performed. A well-defined balance between in vivo and in vitro assays should guide the safety assessment process and include a rationale taking into account ethical considerations as well as associated resourcing involved with animal use. Innovation in de-risking strategies may support refinement of regulatory testing and contribute to (i) improve drug safety evaluation alleviating assessment of the risk-benefit ratio and (ii) promote the access to safe drugs for patients. In this review, promising innovative approaches aiming at facilitating early detection of toxicity during drug development are described.