Fig. 1

Simplified scheme of drug development options. a While screening of preliminary data or literature restricts number of hits (candidates that potentially interfere with a predefined target or pathway) to such already published or rationally identified, b high-throughput screening (HTS) can screen thousands of compounds simultaneously. The latter can be done in vitro using predefined assays with clear read-outs in combination with drug libraries, as well as in silico based on big data to identify drug-drug or drug-disease similarities, or using bioinformatic modeling. c Both approaches result in a number of hits, out of which lead candidates for further development are selected upon further confirmatory testing. d For lead components, further predefined testings are performed, which are amongst others dependent on whether a drug is already approved for other conditions or if the whole drug development process has to be performed. e Resulting candidates can then be taken forward to pre-clinical testings first, and if passing all exigencies, to clinical assessment (f)