Bordeleau, L., Pritchard, K. I., Loprinzi, C. L., Ennis, M., Jugovic, O., Warr, D., . . . Goodwin, P. J. (2010). Multicenter, randomized, cross-over clinical trial of venlafaxine versus gabapentin for the management of hot flashes in breast cancer survivors. Journal of Clinical Oncology: Official Journal of the American Society of Clinical Oncology, 28(35), 5147-5152.

Evaluate the efficacy of venlafaxine versus gabapentin for hot flashes in breast cancer survivors

Patients were randomly assigned to receive venlafaxine for 4 weeks, then after a 2-4 week washout receive gabapentin for 4 weeks, or to have the medications in the reverse order.    Patients were given venlafaxine 37.5 mg daily for 7 days and then 75 mg daily for 21 days.  Gabapentin was given at 300 mg at bedtime for 3 days, then 2 times daily for 3 days, then 3 times daily for 22 days.  Patients completed a hot flash diary daily.  At baseline, and at the end of each study period, they completed a symptom rating and study questionnaires.

• N = 58
• AGE   Median 55, range 39.6 - 78.7
• MALES (%)          FEMALES (%)100%
• KEY DISEASE CHARACTERISTICS
  • All had previous breast cancer and were from 0-20 years since diagnosis. 
  • All had history of bothersome hot flashes. 
  • 79% had hormonal therapy. 
  • 18% had previous treatment for hot flashes.

• SITE  Multi-site 
• SETTING TYPE  Outpatient 
• LOCATION Canada

PHASE OF CARE Late effects and survivorship

Crossover RCT

• SF -36
• Hot flash severity on VAS
• Hot flash diary
• Quality of Life Questionnaire

Only 38 patients completed all 4 weeks of both drugs, and 12% of those initially entered dropped out.  Of patients who provided data regarding drug preference, the majority preferred venlafaxine (p = .01).   There were no significant differences between treatments on hot flash outcomes, and hot flash scores were reduced from baseline in both groups (p<.001).  Venlaxafine was associated with loss of appetite (p<.01), nausea ( p = .02), constipation (p =.05), and fewer negative mood changes (p = .003).  Gabapentin was associated with more dizziness ( p = .005) and increased appetite (p<.001).  Hot flash scores in all subjects increased during the 2-4 weeks off therapy.  There were no serious adverse effects of the medications.

• Both gabapentin and venlaxafine reduced hot flash severity in these patients. 
• Each medication was associated with (differing) side effects. 
• More patients preferred venlaxafine.

• Small sample (< 100)
• Risk of bias (no blinding)
• Subject withdrawals ≥ 10%
• Other limitations/*explanation  It is not clear if patients or observers were blinded to treatment assignments. Subjects not stratified based on age.

The findings suggest that either venlafaxine or gabapentin can be effective in reducing hot flash symptoms in breast cancer survivors.  More patients preferred venlafaxine.  Both drugs have side effects.