Treatment B-A for Healthy Subjects

Researchers are looking for a better way to treat men and women with vasomotor symptoms, a condition of having hot flashes caused by hormonal changes. The study treatment, elinzanetant, is under development to treat symptoms caused by hormonal changes. It works by blocking a substance called neurokinin from sending signals to other parts of the body, which is thought to play a role in starting hot flashes. Participants of this study will be healthy and will have no benefit from administration of elinzanetant. This study, however, will provide information on how to use elinzanetant in people with vasomotor symptoms. In previous studies, capsules containing smaller amounts of elinzanetant have been used. To reach the daily dose intended for treatment, 3 of these capsules had to be taken once a day. To reduce the pill burden and make it easier for patients to stick to the treatment, capsules with a higher amount of elinzanetant have been developed. The main purpose of this study is to learn how much of the study treatment elinzanetant gets into the participants' blood when the same dose is taken as new capsule formulation compared to the old capsule formulation. To answer this question, the researchers will compare: The (average) total level of elinzanetant in the blood (also called AUC) The (average) highest level of elinzanetant in the blood (also called Cmax) between both capsule formulations after taking one dose of each. In addition, the researchers want to compare how much of the new and old elinzanetant formulations get into the blood after intake for 9 subsequent days. All participants will take both formulations by mouth during the study. Each participant will be in the study for up to 12 weeks, including 10 treatment days for each formulation. Participants will stay in-house for 14 days per capsule formulation. In addition, one screening visit to the study site is planned. During the study, the study doctor and their team will: Do physical examinations Take blood and urine samples Check vital signs Examine the participants' heart health using electrocardiogram (ECG) Ask the participants questions about how they are feeling and what adverse events they are having. An adverse event is any medical problem that a participant has during a study. The study doctors keep track of all adverse events that happen in studies, even if they do not think the adverse events might be related to the study treatments.