In vivo effect of I’m-Yunity on hepatic cytochrome P450 3A4.

Nicandro JP, Tsourounis C, Frassetto L, Guglielmo BJ.

Dept of Clinical Pharmacy, University of California, San Francisco, CA 94143, USA.


The inhibition or induction of hepatic cytochrome P450 3A4 (CYP3A4) enzyme associated with herbal medicines such as I’m-Yunity (Coriolus versicolor) can result in clinically significant herb-drug interactions. The active ingredient of I’m-Yunity is believed to be polysaccharopeptide polymer (PSP). Drug interactions between I’m-Yunity and other medications or supplements are yet to be investigated. The objective of this single-treatment, one-period, three-phase, open-labeled study was to evaluate the ability of I’m-Yunity to inhibit or induce CYP3A4 in 12 healthy adult volunteers (8 women and 4 men) aged between 23 and 54 years through the use of a CYP3A4-specific assay, the erythromycin breath test (EBT). EBT measurements are reported as percentage of 14C-Erythromycin metabolized/hr. Participants were given a 14-day supply of I’m-Yunity and instructed to take 1200 mg, three times daily with meals. Comparisons of all subjects’ mean CYP3A4 activities were performed with the EBT before and after taking I’m- Yunity. Results revealed a mean EBT change (SD) from baseline of 0.08% (0.56%) 14C-Erythromycin metabolized/hr, which was not significant (p = 0.63). Therefore, 14 days of exposure to I’m-Yunity was not associated with clinically significant CYP3A4 inhibition or induction, suggesting that short-term administration of I’m-Yunity with medications primarily metabolized by CYP3A4 is safe and not expected to be associated with significant herb-drug interactions. However, it is still unknown whether interactions exist between I’m-Yunity and other medications metabolized by other CYP450 isozymes or enzyme/transporter systems.

PMID: 17594986 [PubMed – indexed for MEDLINE]