A study to assess long-term safety of fezolinetant given to Japanese women going through menopause

Hot flashes are the most common reason women going through menopause seek medical attention. Hormone replacement therapy, or HRT, is most often prescribed to treat hot flashes. However, HRT can’t be used by all women or for as long as may be needed.

Researchers want to find other ways to treat hot flashes. Fezolinetant is a medicine to treat hot flashes in women going through menopause. Fezolinetant is an approved medicine in the US. Further studies are needed before it is available in other regions such as Asia.

In this study fezolinetant will be used to treat hot flashes in Japanese women going through menopause. This study will confirm the safety of fezolinetant and how well the women tolerate the treatment.

Women will either take fezolinetant or a placebo. This is decided by chance alone. The placebo looks like fezolinetant but will not have any medicine in it.

The women will take 1 tablet of the study medicine (fezolinetant or the placebo) once a day for up to 52 weeks.

During the study, the women will visit their study clinic for a check-up about every 4 weeks for up to 52 weeks (1 year). At each visit they will be asked if they had any medical problems. Other checks will include a medical examination and vital signs (temperature, blood pressure and pulse). At some visits, the women will have an ECG to check their heart rhythm and some blood and urine samples will be taken for laboratory tests. During a couple of visits, women who have a womb (uterus) will also have a test called a transvaginal ultrasound. A probe is gently placed inside the vagina. Sound waves will create a picture of the organs in the pelvis. This will allow the study doctor to look more closely at the uterus and surrounding organs.

The last clinic visit will be 3 weeks after the women take their final tablet of the study medicine (fezolinetant or the placebo).