An object is to provide a composition and a method for eliminating undifferentiated pluripotent stem cells remaining in a cell group induced to differentiate from pluripotent stem cells. It has been found that while dihydroorotate dehydrogenase inhibitors exhibit cytotoxic activity against pluripotent stem cells, they do not exhibit significant cytotoxic activity against differentiated cells such as somatic stem cells.

The invention provides methods of determining a therapeutically effective dose of an agent that targets a metabolic pathway based on measured levels of a metabolite in the pathway. The methods, which may include providing the agent in a therapeutically effective dose, are useful for treating disorders, such as cancer, in a subject. The invention also provides methods for assessing the impact of a therapeutic agent on a tumor in a subject by monitoring, in real time, metabolism of a molecule in the tumor, oxygenation of the tumor, or both. The invention further provides devices that determine a therapeutically effective dose of an agent that targets a metabolic pathway based on measured levels of a metabolite in the pathway and notify a subject to administer the dose.