A Study to Examine the, Safety, Tolerability and Pharmacokinetics Co-Administered Baclofen and Memantine in Obese and Lean, Otherwise Healthy Adults

Inclusion Criteria: 1. Adult males or females aged 18 to 45 years inclusive; 2. Subjects with body mass index: For Part A: ≥18 kg/m² and ≤25 kg/m²; For Part B: ≥33 kg/m² and ≤40 kg/m². 3. Subjects with a total body weight of ≥50 kg (Part A and Part B); 4. Subjects who are healthy as determined by the Investigator based on pre study medical history, physical examination, vital signs (blood pressure, pulse rate, respiratory rate and body temperature) and 12-lead ECG at screening and each admission; 5. Subjects whose clinical laboratory test results are not clinically relevant and are acceptable to the Investigator at screening and each admission; 6. Aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and bilirubin ≤1.5 x upper limit of normal (ULN); 7. Subjects who are negative for hepatitis B surface antigen (HBsAg), hepatitis C antibody and human immunodeficiency virus (HIV) I and II tests at screening; 8. Subjects who are negative for drugs of abuse and alcohol tests at screening and each admission; 9. Subjects who are non-smokers or who have not smoked or used nicotine-containing products for at least 3 months prior to screening; 10. Subjects with an estimated creatinine clearance ≥100 mL/minute for male subjects or ≥90 mL/minute for female subjects (Cockcroft-Gault method) at screening; 11. Subjects who are able and willing to give written informed consent.