RESUMEN
OBJECTIVE: To discuss early exploratory bridging studies between early screening phase and pivotal general toxicology studies and their application during new drug development. METHODS: The opinions on acute toxicity study from international counterparts and current application in domestic and overseas were briefly reviewed. At the same time, the study design and the strengths of an alternative maximum tolerated dose /dose range finding (MTD/DRF) study widely used abroad were fully discussed. Furthermore, considerations were also highlighted based on the authors' experience, which may aid in the design and the conduct of such bridging studies. RESULTS AND CONCLUSION: MTD/DRF study could provide more valuable information for subsequent non-clinical regulatory toxicity studies. It is a rational and practical general toxicological study with bridging character.