Baicalin, an emerging multi-therapeutic agent: pharmacodynamics, pharmacokinetics, and considerations from drug development perspectives

Abstract

1. Baicalin was extensively researched for utility in a number of therapeutic areas owing to its anti-inflammatory, anti-oxidant, anti-bacterial, and anti-cancer properties.

2. A number of preclinical studies, in vitro work, and mechanistic studies were performed to understand the absorption, distribution, metabolism, and excretion profiles of baicalin.

3. The absorption of baicalin involved several complexities: the restriction to two distant sites; the conversion of baicalin to baicalein; the possible role of transporter(s); and enhanced absorption due to breakdown of conjugates by beta-glucuronidase.

4. Limited distribution data suggest that baicalin reached several sites such as the brain, eye lens, thymus, etc. Hepatobiliary recycling also served as a distribution phase for sustained delivery of baicalin.

5. Metabolism data suggest the rapid conversion of baicalin to baicalein, which was extensively subjected to Phase 2 metabolism, conjugates baicalein glucuronide/sulfate have been identified.

6. Limited excretion data suggest involvement of renal and faecal routes—glucuronide and sulfate conjugates were excreted in urine and faeces (via biliary excretion).

7. The published data on baicalin suggest imminent challenges for developing baicalin and/or during co-administration with other agents. These challenges are absorption related (transporter or changes in the microenvironment), metabolism related (CYP2B6 induction and/or CYP2E1 inhibition), and excretion/efflux related (competitive biliary pathway and/or OATP1B1 transport).

Keywords::

• Baicalin
• pharmacokinetics
• drug development
• pharmacodynamics
• drug–drug interaction

Acknowledgements

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.