A Randomized Phase II Study to Evaluate the Efficacy of Fezolinetant in Reducing Vasomotor Symptoms in Women With Breast Cancer on Endocrine Therapy
This is a phase II, randomized, placebo-controlled trial designed to evaluate the efficacy of fezolinetant (45 mg a day) vs. placebo in reducing moderate to severe vasomotor symptoms (VMS) in breast cancer survivors on endocrine therapy (tamoxifen, aromatase inhibitors). The trial will proceed in a single stage and the total of 92 patients will be randomized in 1:1 fashion to fezolinetant or placebo arm respectively.
• Women with diagnosed, histologically confirmed, clinical stage I-III, HR+ invasive breast cancer as defined by ASCO CAP guidelines for whom adjuvant endocrine therapy would be indicated.
• BMI of 18-38 kg/m2
• Age 40-65
• Currently on endocrine therapy (tamoxifen or aromatase inhibitors)
• Willing and able to provide written informed consent/assent for the trial.
• Postmenopausal as defined by spontaneous amenorrhea for at least 12 consecutive months, spontaneous amenorrhea for at least 6 months with biochemical criteria or menopause (FSH \> 40 IU/L), or bilateral oophorectomy for at least 6 weeks before the screening visit, or if premenopausal chemically suppressed by GnRH agonist therapy with ultrasensitive estradiol level \<10.
• On endocrine therapy for a minimum of 3 months and has planned duration of 12 weeks left in the treatment regimen.
• Experiencing an average of seven or more moderate to severe hot flashes per day over a 7-day period as documented by Symptom Diary during the Screening Period and seeking treatment or relief for VMS.
• Able to swallow oral formulation of the study agent.