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The NCATS high-throughput robotic screening system.

Tox21 Collaborators Release Strategic Plan for Chemical Testing

Leaders of the Toxicology in the 21st Century (Tox21) program have published a strategic and operational plan to address new research challenges.


Anticancer cells on a laptop

NCATS, Karolinska Institutet Scientists Attack Cancer’s Defenses

Scientists from NCATS and Sweden’s Karolinska Institutet have developed a potential new approach to fighting cancer by breaking down a defense system used by cancer cells.


Work with Us

NCATS pre-clinical programs and resources focus on key obstacles and inefficiencies in the translational process, overcoming bottlenecks that slow the development of new treatments for patients.

Learn more about how to access NCATS programs and expertise.

Testing & Predictive Models

Developing better model systems for drug and toxicity testing. Learn more.

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Efficacy & Toxicology

Providing the research community with robust, reliable tools for testing chemical safety and efficacy.

Molecular Targets

Developing new methods to validate potential drug targets efficiently and predictably.

Core Technologies

Using state-of-the-art resources to enable the ongoing operation of all NCATS translational research activities.

Translational Science Spectrum

Learn more about the science of translation.

Drug and Toxicity Testing at NCATS

Predicting biological effects of drugs, chemicals and therapeutic interventions is fraught with hazard. Approximately 80 percent of candidate drugs fail in human clinical trials because they are found to be unsafe or ineffective. More than 30 percent of promising medications have failed in clinical trials because they are found to be harmful to human health (i.e., they have high toxicity), despite costly pre-clinical studies in animal and cell models. Because these models often do not adequately represent human biology, they do not always accurately reflect how patients will react to an experimental compound.

A major area of emphasis at NCATS is the development of model systems for drug and toxicity testing that more closely resemble human physiology. Such advances could save enormous amounts of time and expense by preventing patients from being exposed to potentially harmful or ineffective candidate drugs in clinical studies. In addition, these models have the potential to provide useful information about the basic biology of disease and serve as improved testing platforms for predicting toxicity or other physiological processes as well as evaluating environmental chemicals.