Evaluation of the Safety, Tolerability, and Pharmacokinetics of J4 in Healthy Adults

This study is testing a new investigational drug called J4 for the first time in healthy adults. The goal is to assess whether the drug is safe, how well it is tolerated, and how the body processes it. This is a Phase 1 safety study — participants will be closely monitored. **You may be eligible if...** - You are a healthy adult between 18 and 64 years old - Your BMI is between 18 and 30 - You have no clinically significant health conditions based on physical exams, blood tests, and heart monitoring - You are willing to use highly effective contraception during the study and for 90 days after the last dose **You may NOT be eligible if...** - You have any significant health conditions identified during screening - You are pregnant, breastfeeding, or planning to become pregnant - You are unwilling or unable to use the required contraception methods - You have a history of significant drug or alcohol use that could affect the study Talk to your doctor to see if this trial is right for you.