In this study, researchers will learn how the heart reacts to multiple doses of BIIB091 in healthy participants. In previous studies looking at BIIB091, researchers have found that a certain range of doses can cause changes in the electrical activity of the heart. In this study, researchers want to learn more about that activity after participants take BIIB091 at lower and higher doses for 5 days. The main objective of this study is to learn how the heart's electrical activity changes after taking BIIB091. To measure this, researchers will look at something called the QT interval corrected for heartbeat, also known as "QTc". This represents the time it takes for the heart to contract and relax. A QT interval that is too long means that the heart's electrical system is taking longer than normal to recharge between heartbeats. This could increase the risk of abnormal heartbeats that may lead to sudden death. The main questions researchers want to answer are: • What is the change in the participants' QTc after taking BIIB091? Researchers will also learn more about: * Any changes in other measures of the heart's electrical activity * How the body processes BIIB091, as well as something called "M23", which is made in the body when BIIB091 is broken down * Any medical problems the participants have during the study * Any changes in the participants' overall health during the study This study will be done as follows: * Participants will be screened to check if they can join the study. The screening period will be up to 29 days, after which participants will check into their study research center. * Participants will be randomly assigned to be in 1 of 2 groups: * Group 1: Participants will take a low dose of BIIB091 for 5 days followed by a high dose of BIIB091 for 5 days. * Group 2: Participants will take a single dose of moxifloxacin. Moxifloxacin is an antibiotic used to treat bacterial infections. Researchers are using it in this study to compare to BIIB091, because it is known to cause abnormal changes to the heart's electrical activity. * Participants in both Group 1 and Group 2 will also take a placebo while at the study research center. A placebo looks like the study drug or moxifloxacin, but does not have any real medicine in it. * Participants will remain at their study research center for 15 days. Afterwards, there will be a follow-up visit 11 to 14 days after each participant's last dose. Each participant will be in the study for up to 57 days.
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Change From Baseline in QT Interval Corrected for Heart Rate (QTc) for BIIB091
Timeframe: Baseline (Day -1) up to Day 14
Change From Baseline in QT Interval Corrected for Heart Rate (QTc) for Metabolite 23 (M23)
Timeframe: Baseline (Day -1) up to Day 14