A study in healthy volunteers to determine whether different drugs metabolised by the liver have any effects on how NRL972 is processed within the body.

Inclusion Criteria:

1. Males or females (females of non-childbearing potential or of childbearing potential while taking medically appropriate contraception)
2. Caucasian
3. Age: 21 - 40 years
4. BW 50 - 100 kg
5. BMI 20 - 26 kg.m-2
6. healthy based on the pre-study examination
7. willing and able to provide informed consent

Exclusion Criteria:

General - all subjects

1. Previous participation in the trial

2. Participant in any other trial during the last 90 days

3. Donation of blood during the last 60 days or a history of blood loss exceeding 300 mL within the last 3 months

4. History of any clinically relevant allergy (including hypersensitivity to the trial medications)

5. Presence of acute or chronic infection

6. Presence or history of any relevant co-morbidity

7. Resting systolic blood pressure > 160 or < 90 mmHg, diastolic blood pressure > 95 or < 50 mmHg

8. Clinically relevant ECG-abnormalities, prolonged QTc with > 450 msec in males and > 460 msec in females in particular

9. Presence of any relevant abnormality in the laboratory safety tests, especially low haemoglobin, increased liver enzymes

10. Positive serology for HBsAg, anti HBc and anti HCV

11. Positive HIV test

12. Positive alcohol or urine drug test on recruitment (and upon admission)

13. History of alcohol and/or drug abuse and/or daily use of > 30 gr alcohol

14. Smoking more than 15 cigarettes/day or equivalent of other tobacco products

15. Use of prohibited medication

16. Suspicion or evidence that the subject is not trustworthy and reliable

17. Suspicion or evidence that the subject is not able to make a free consent or to understand the information in this regard

    General - all females

18. Positive pregnancy test

19. Lactating

20. Not using appropriate contraception in pre-menopausal women (note: under the conditions of the present study, women using hormonal contraceptives will be informed that this method is not sufficient during the study and that further i.e. mechanical methods [condom, diaphragm with spermicidal gel] should be us