Clinical development and informatics analysis of natural and semi-synthetic flavonoid drugs: A critical review

•This is the most systematic review of flavonoid drugs and clinical candidates to date.•19 flavonoid drugs are approved for the market, while 36 candidates in clinical phases.•52.6% of the marketed flavonoid drugs and 44.4% of clinical candidates are natural sources.•30% of the marketed flavonoid drugs are used for the treatment of cardiovascular diseases.•50% of the suspended clinical candidates are antineoplastic and immunomodulating agents.•Unexpectedly, flavonoid glycosides account for 36.8% of the marketed flavonoid drugs.