Trials and Tribulations of Planning and Conducting a Phase 2 Clinical Trial with Black Cohosh and Red Clover

A Phase 2 clinical trial with Black Cohosh and Red Clover was conceived in 2000 within our UIC/NIH Center for Botanical Dietary Supplement Research on Women's Health. Prior to implementing the trial, a Phase 1 study was required and approval from FDA that an IND application was not required since the end point being measured was reduction in hot flashes in menopausal women. Menopause, for purposes of FDA is not considered a disease. The study was delayed for more than a year in order to prepare a botanically authenticated and chemically and biologically standardized extract. It was ascertained that the biological endpoint for purposes of the study would be interaction with certain serotonin receptors, in vitro. The study preparations had to be formulated and were subjected to accelerated stability studies. During the recruitment of suitable subjects the results of the WHI (Women's Health Initiative) caused difficulty in the ability to recruit suitable women since the study had four arms, i.e. Black Cohosh, Red Clover, Placebo and Prempro and many women were reluctant to enter the trial if there was a possibility that there would be taking Prempro. Because of this, only 88 subjects were recruited of the 128 initially planned. However, the study was powered sufficiently if the dropout rate was less than 15%. In the final analysis, Red Clover was shown to positively affect cognition but neither test preparation reduced hot flashes. A discussion of these results will be presented.