Rostock, M., Fischer, J., Mumm, A., Stammwitz, U., Saller, R., & Bartsch, H. H. (2011). Black cohosh (Cimicifuga racemosa) in tamoxifen-treated breast cancer patients with climacteric complaints - a prospective observational study. Gynecological Endocrinology, 27(10), 844-848.

The purpose of this study was to evaluate the dosage, effectiveness, and tolerability of an isopropanolic extract of black cohosh (Cimicifuga racemosa) in patients with breast cancer taking tamoxifen and reporting menopausal symptoms.   

The study drug, Remifenin, was dosed at 2 tablets by mouth per day (40 mg black cohosh total) for 4 weeks but then participants could self-escalate the dose per patient preference (20, 40, 60, or 80 mg) and continue daily tablets for up to 6 months (mean 134 days). Participants were assessed at baseline and again 3- and 6-months later (90 and 180 days later). A subset of 4 patients also took St. John’s Wort.

• 50 participants completed baseline, 47 completed first assessment, 40 secondassessment, and 35 final assessment. All available participants were used in the analyses.
• AGE:  Mean age of 56 years (range 43-77), no age SD reported.
• MALES (%)  0%    FEMALES (%)  100%
• KEY DISEASE CHARACTERISTICS:  All stages of breast cancer, estrogen receptor positive (n=44, 94%), metastases (n=4, 9%)
• OTHER KEY SAMPLE CHARACTERISTICS:  Mean of 8.6 months post diagnosis, 74% postmenopausal, 100% taking tamoxifen

• SITE: Single site   
• LOCATION: Germany
   

• PHASE OF CARE: Transition phase after initial treatment
• APPLICATIONS: Late effects & survivorship

Prospective, longitudinal, non-randomized study

• Menopause rating scale - self-assessment, profile and intensity of 11 menopausal symptoms, subscores for symptom domains of vegetative-somatic, psychic, and urogenital symptoms
• Physician documentation of tumor characteristics

There was a significant reduction in menopause rating scale scores, total scores, and subscales of vegetative-somatic and psychic symptoms at 1, 3, and 6 months of treatment. The overall MRS II score significantly decreased from 17.6 to 13.6 between baseline and last observation (p<0.001).   Two of the three symptom subscales also decreased significantly (vegetative-somatic and psychic both p<0.01).  However, the was no evidence of effectiveness for urogenital symptoms.  Symptoms that were initially most intense such as hot flashes, sweating, and sleep disturbances improved most during the observation period.

The effectiveness of black cohosh extract for treatment of menopausal symptoms among women taking adjuvant tamoxifen is still unclear.  Daily use over at least 4 weeks may result in reduced hot flashes and sleep disturbances.  The drug was well tolerated in the small sample; however, it is unclear what the ideal dosing is for therapeutic benefit.

Limitations of the study included:

• No appropriate control group
• Small, non-randomized study  
• 30% drop out rate over 6 months 
• Dosage varied
• Use of St. John’s Wort known to interfere with CYP450 isoenzymes and could have affected tamoxifen metabolism and the resulting side effects 
• Did not study possible impact on hormones
   

Black cohosh could be studied in a randomized trial but this study does not provide any efficacy information in relation to placebo.