Inclusion Criteria:  Able and willing to give written informed consent and to comply with the study restrictions; Male or female subjects aged 18 to 45 years, inclusive; Body mass index (BMI) between 18 and 30 kg/m2, inclusive; Healthy as determined by pre-study medical history, physical examination, vital signs, complete neurological examination and 12-lead electrocardiogram (ECG); Negative tests for hepatitis B surface antigen (HBsAg), anti-hepatitis C virus antibodies (HCV Ab) and anti-human immunodeficiency virus antibodies (HIV-1 and HIV-2 Ab) at screening; Clinical laboratory test results clinically acceptable at screening and admission to each treatment period; Negative screen for alcohol and drugs of abuse at screening and admission to each treatment period;  Non-smokers or ex-smokers for at least 3 months.  If female:  No childbearing potential by reason of surgery or at least 1 year post menopause (i.e., 12 months post last menstrual period), or menopause confirmed by follicle-stimulating hormone (FSH) testing; If of childbearing potential, she was using an effective non-hormonal method of contraception [intrauterine device or intrauterine system; condom or occlusive cap (diaphragm or cervical or vault caps) with spermicidal foam or gel or film or cream or suppository; true abstinence; or vasectomized male partner, provided that he is the sole partner of that subject] for all the duration of the study;  Negative serum pregnancy test at screening and negative urine pregnancy test on admission of each treatment period (women of childbearing potential only).  If male:  Using an effective method of contraception with a pregnant partner or partner of childbearing potential (condom or occlusive cap [diaphragm or cervical or vault caps] with spermicidal foam or gel or film or cream or suppository; true abstinence; or vasectomy) throughout the study; Refraining from donating sperm throughout the study.  Exclusion Criteria:  Clinically relevant history or presence of respiratory, gastrointestinal, renal, hepatic, haematological, lymphatic, neurological, cardiovascular, psychiatric, musculoskeletal, genitourinary, immunological, dermatological, endocrine, connective tissue diseases or disorders; Clinically relevant surgical history; History of relevant atopy or drug hypersensitivity; History of alcoholism or drug abuse; Consumption of more than 14 units of alcohol a week [1 glass (25 cL) of beer with 3° of alcohol = 7.5 g, or 1 glass (25 cL) of beer with 6° of alcohol = 15 g, or 1 glass (12.5 cL) of wine with 10° of alcohol = 12 g, or 1 glass (4cL) of aperitif with 42° of alcohol = 17 g]; Significant infection or known inflammatory process at screening or admission to each treatment period; Display of acute gastrointestinal symptoms (e.g., nausea, vomiting, diarrhoea, heartburn) at the time of screening or admission to each treatment period; Use of medicines within 2 weeks of admission to the first period that may could affect the safety or other study assessments, in the Investigator's opinion; Previous administration of BIA 5-1058; Use of any investigational drug or participation in any clinical trial within 90 days prior to screening; Participation in more than 2 clinical trials within the 12 months prior to screening; Donation or reception of any blood or blood products within the 3 months prior to screening; Vegetarians, vegans or had any other medical dietary restrictions; Not able to communicate reliably with the Investigator;  Unlikely to co-operate with the requirements of the study.  If female:  Pregnant or breastfeeding;  Not using an accepted effective contraceptive method or was using oral contraceptives.  If male:  Not using an accepted effective method of contraception; Refusing to refrain from donating sperm throughout the study.