Hot flushes are the most common complaints reported by men undergoing androgen suppression treatment for prostate cancer. We designed a randomised double-blind trial to compare the efficacy of three drugs, each of which has proven effective for preventing hot flushes in previous studies.

Men with prostate cancer with an indication for androgen suppression were enrolled in the study at 106 urology centres in France between April 14, 2004, and April 20, 2007. All patients were treated for 6 months with leuprorelin (11.25 mg). At month 6, patients who spontaneously asked for treatment, or those who presented with 14 hot flushes or more during the week before the visit, were randomly assigned to either venlafaxine 75 mg daily, medroxyprogesterone acetate 20 mg daily, or cyproterone acetate 100 mg daily. All patients received two indistinguishable pills in the morning and one in the evening from week 1 to week 8, and one indistinguishable pill in the morning from week 9 to week 10, to comply with the double-blind design. Random assignment with a block size of three was done centrally, by fax, and each patient was given a randomisation number. The allocation sequence was stratified by centre. Assessment was done at inclusion, at randomisation, and then at 4 weeks, 8 weeks, and 12 weeks after randomisation. Participants completed a daily hot-flush diary for 1 week, and a quality of life questionnaire before each visit throughout the study. The primary outcome was the change in median daily hot-flush score between randomisation and 1 month. All patients who received at least one study treatment dose were included in the efficacy analysis. This trial is registered with ClinicalTrials.gov, number NCT01011751.

Of the 919 men initially enrolled, 311 were randomly assigned to one of the study treatments at 6 months: 102 to venlafaxine, 101 to cyproterone, and 108 to medroxyprogesterone. 309 patients were included in the efficacy analysis, since two were excluded for protocol deviations (one in the cyproterone and one in the medroxyprogesterone group; both were excluded because they were already undergoing treatment with serotonin reuptake inhibitor antidepressants at randomisation). The change in median daily hot-flush score between randomisation and 1 month was -47.2% (IQR -74.3 to -2.5) in the venlafaxine group, -94.5% (-100.0 to -74.5) in the cyproterone group, and -83.7% (-98.9 to -64.3) in the medroxyprogesterone group. The decrease from baseline was significant for all three groups (p<0.0001). Pairwise comparison of treatment groups adjusted by the Bonferroni method confirmed that the decreases in hot-flush score were significantly larger in the cyproterone and medroxyprogesterone groups than in the venlafaxine group, regardless of the interval considered (p<0.0001 in all cases). There was no significant difference between the cyproterone and medroxyprogesterone groups (p>0.2 in all cases). Serious side-effects occurred in four, seven, and five patients in the venlafaxine, cyproterone, and medroxyprogesterone groups, respectively, of which none, one (dyspnoea), and one (urticaria) were considered related to the drug, respectively.

After 6 months of treatment with leuprorelin, venlafaxine, cyproterone, and medroxyprogesterone proved to be effective in reducing hot flushes. However, the hormonal treatments cyproterone and medroxyprogesterone were significantly more effective than venlafaxine. As cyproterone is a recognised treatment in prostate cancer, and its use could interfere with hormonal therapy, medroxyprogesterone could be considered to be the standard treatment for hot flushes in men undergoing androgen suppression for prostate cancer.

Takeda Laboratories, Puteaux, France.