This study is for women in menopause with hot flashes. Menopause, a normal part of aging, is the time of a woman's last period. Hot flashes can interrupt a woman's daily life.
The purpose of this study is to find out how safe it is for these women to take fezolinetant long term (up to 52 weeks). To do that, the study will look at the number and severity of the "adverse events." Those are the side effects that study participants have while they are in the study.
The study treatments are fezolinetant low dose (1 tablet of fezolinetant and 1 placebo tablet) once a day, fezolinetant high dose (2 tablets of fezolinetant) once a day or placebo (2 tablets) once a day. (Placebo is a dummy treatment that looks like medicine but does not have any medicine in it.) Women in this study will be picked for 1 of the 3 study treatments by chance alone. The study participants will take study treatment for 52 weeks.
This study is "double-blinded." That means that the study participants and the study doctors do not know who takes which of the study treatments (fezolinetant low dose, fezolinetant high dose or placebo).
At weeks 2 and 4 and then once a month, the study participants will go the hospital or clinic for a check-up. They will be asked about medications, side effects and how they feel. Other checks will include physical exam and vital signs (heart rate, temperature and blood pressure). Blood and urine will be collected for laboratory tests. At some study visits, study participants will complete questionnaires that are about their quality of life.