The study drug is elinzanetant and it is an investigational drug. It is not approved yet for sale in any country. Elinzanetant can only be used in studies like this one.

Looking for healthy female participants suffering from moderate to severe hot flashes that would like to try using an investigational medication or placebo daily for 52 weeks to treat their hot flashes.

Required screening procedures are physical exam, pap smear, mammogram, vaginal ultrasound, endometrial biopsy, bone mineral densitometry, and blood work.

No one can choose which drug you will get. This includes you, the study doctor, and the study sponsor. The researchers will use a computer program to randomly choose which drug you will get. This helps make sure the drugs are chosen fairly and comparing the results of the drugs are as accurate as possible.

1. You will have a 1 in 2 chance of getting elinzanetant.

2. You will also have a 1 in 2 chance of getting placebo (sugar pill).

You and your study doctor will not know which drug you will be taking. But your study doctor can find out in case of an emergency.

You will take 2 capsules of elinzanetant or a matching placebo daily before going to bed, with or without food for 52 weeks.

Study participants will be in the study for up to about 15 months and you will visit the study site about 11 times and have two phone calls (phone visits) related to this study.

Participants are compensated for time and travel