Single centre, open-label, randomised, three-way crossover study in 18 healthy subjects (9 males and 9 females). The study consisted of three consecutive single-dose treatment periods separated by a washout period of 7 days or more. On each treatment period, the volunteers received a single dose of BIA 2-093 800 mg, orally.

Sample size (planned and analyzed): It was planned to have at least 16 healthy subjects completed and evaluable. Taking into account the potential occurrence of dropouts, two additional subjects were to be recruited and entered the study. Therefore, a total of 18 subjects were enrolled.

Diagnosis and main selection criteria: Healthy male or female volunteers aged between 18 and 45 years, with body mass index between 19 and 28 kg/m2, non-smokers or smoking less than 10 cigarettes or equivalent per day.

Inclusion Criteria:

• Male or female subjects aged between 18 and 45 years, inclusive.
• Subjects of body mass index (BMI) between 19 and 28 kg/m2, inclusive.
• Subjects who were healthy as determined by pre-study medical history, physical examination, vital signs and 12-lead ECG at screening.
• Subjects who had clinical laboratory tests clinically acceptable at screening.
• Subjects who were negative for HBsAg, anti-HCV Ab and HIV-1 and HIV-2 Ab tests at screening.
• Subjects who were negative for alcohol and drugs of abuse at screening.
• Subjects who were non-smokers or who smoke less than 10 cigarettes or equivalent per day.
• Subjects who were able and willing to give written informed consent.
• (If female) She was not of childbearing potential by reason of surgery or, if of childbearing potential, she used one of the following methods of contraception: doublebarrier, intra-uterine device or abstinence.
• (If female) She had a negative pregnancy test at screening and admission to each study period.

Exclusion Criteria:

• Subjects who do not conform to the above inclusion criteria, or
• Subjects who have a 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.
• Subjects who have a clinically relevant surgical history.
• Subjects who have a clinically relevant family history.
• Subjects who have a history of relevant atopy.
• Subjects who have a history of any drug hypersensitivity.
• Subjects who have a history of alcoholism or drug abuse.
• Subjects who consume more than 14 units of alcohol a week.
• Subjects who have a significant infection or known inflammatory process on screening and/or first admission.
• Subjects who have acute gastrointestinal symptoms at the time of screening and/or first admission (e.g., nausea, vomiting, diarrhoea, heartburn).
• Subjects who have used medicines within 2 weeks of admission to first period.
• Subjects who have participated in any clinical trial within 3 months prior to screening.
• Subjects who have previously received BIA 2-093.
• Subjects who have donated and/or received any blood or blood products within the previous 3 months prior to screening.
• Subjects who are vegetarians, vegans and/or have medical dietary restrictions.
• Subjects who cannot communicate reliably with the investigation team.
• Subjects who are unlikely to co-operate with the requirements of the study.
• Subjects who are unwilling or unable to give written informed consent.
• (If female) She is pregnant or breast-feeding.
• (If female) She is of childbearing potential and she does not use an approved effective contraceptive method or she uses oral contraceptives.