The primary purpose of the trial is to investigate the pharmacokinetics (behaviour of the compound in the body) of safinamide in subjects with different degrees of renal impairment in comparison to matched subjects with normal renal function.

Inclusion Criteria:

1. Renally impaired subjects - Subject with different degrees of renal impairment: moderate and severe renal impairment as assessed by Estimated Glomerular Filtration Rate (eGFR) according to Modification of Diet in Renal Disease (MDRD) equation at screening
2. Healthy subjects - Subject is in good age-appropriate physical and mental health as established by medical history, physical examination, electrocardiogram (ECG) and vital signs recordings, and results of biochemistry, haematology, coagulation and urinalysis testing within 3 weeks prior to dosing
3. All subjects have given written informed consent before any study-related activities are carried out

Exclusion Criteria:

1. Any other clinically relevant disease, condition, or therapy, which in the Investigator's opinion would exclude the subject from the trial, may pose a risk to the subject or interfere with the trial objectives.
2. Existence of surgical or medical condition, which, in the judgment of the Investigator, might interfere with the absorption, metabolism, or excretion of the drug and/or gastrointestinal motility
3. Renally impaired subjects - Acute renal failure of any etiology (including viral, toxic, or drug induced), renal transplantation within the previous 12 months, uncontrolled diabetes mellitus as judged by the Investigator, use of any drug affecting gastric acid secretion, such as proton pump inhibitors and antacids received within 48 hours prior to drug administration and for 24 hours after administration, Chronic heart failure (CHF) New York Heart Association (NYHA) class III and IV despite treatment at screening, change in used medication (prescribed by a physician or over-the-counter [OTC] medication) within 14 days prior to safinamide administration. Concomitant medication used for the treatment of renal impairment and accompanying diseases may be continued during the trial.
4. Healthy subjects - Use of any medication, including multi-vitamin preparations, received within 21 days prior to drug administration (or within six times the elimination half-life, whichever is longest), except combined oral contraceptives and occasional use of paracetamol or ibuprofen within 14 days before trial drug administration.