Table 1.

Factors to be considered before submission of a repurposing study

Is there experimental evidence to support the proposed mode of action and to validate any calculated data?	Present this experimental data explicitly Distinguish carefully between measured and calculated data
	Be careful to check cited references, to ensure they do contain experimental data and not in silico estimates
	Is the mode of action specifically (target or pathway) or non-specifically (physicochemical property) driven?
Are the experimental activities significant?	Cell-based assay: better than 1 microM
	Biochemical assay, better than 100 nM
	Virtual screening results on their own are not sufficient
Is there a clear causal link between the proposed mode of action and any clinical observations?
Can be it shown that the candidate should be safe and efficacious at established dosing protocols?	Compare the concentrations required for effect at the target with the NOAEL and PK parameters