Safety, Pharmacokinetics, and Pharmacodynamics of MTX-101 in Healthy Adults and Patients

This is an early-stage safety study testing a new investigational drug called MTX-101 in healthy adults. The study is designed to understand how the drug behaves in the body — how it is absorbed, how long it stays in the blood, and what effects it has — before testing it in patients with specific conditions. **You may be eligible if:** - You are between 18 and 65 years old - You are generally healthy with no known chronic medical conditions or autoimmune diseases - Your body weight and BMI are within the study range (BMI 18–35; weight 55–120 kg) - You tested negative for COVID-19 within 24 hours before each dose - You are willing to use effective contraception or abstain from sex during the study (if of childbearing potential) **You may NOT be eligible if:** - You have clinically significant abnormal findings on physical exam, vital signs, or ECG - You have a history of autoimmune disease - You are pregnant or planning to become pregnant - You have significant liver, kidney, or cardiovascular conditions - You have used certain medications within a specified time before the study Talk to your doctor to see if this trial is right for you.