This study will assess the effect of dexpramipexole on the pharmacokinetics (PK) of the CYP2C9 probe substrate warfarin in healthy volunteers.

This is a single center open label study to assess the effect of Dexpramipexole on the PK of Warfarin in Healthy Volunteers. The goals of this study are as follows: to assess the effect of dexpramipexole on the pharmacodynamics (PD) of warfarin, to assess the safety and tolerability of dexpramipexole when administered alone, and with warfarin, and to assess the PK of dexpramipexole when administered alone; to explore the influence of genetic variation on the PK and international normalized ratio (INR) of warfarin when administered alone, and with dexpramipexole; and to explore the influence of genetic variation on the PK of dexpramipexole when administered alone.

Inclusion Criteria:

• Subjects who, in the opinion of the investigator, are healthy as determined by medical history, physical examination, and 12 Lead ECG.
• Adult males/females aged 18 to 55 years inclusive.
• Male and female subjects of childbearing age must practice effective contraception during the study and up to 90 days after their last dose of study drug.

Exclusion Criteria:

• History of malignant disease, including solid tumors and hematologic malignancies.
• Clinically significant current active infection or serious infection.
• History of gastrointestinal bleeding, peptic ulcer disease, hemorrhoids or epistaxis.
• Personal or family history of any bleeding disorder, and/or coagulation profile results outside of normal limits.
• Known allergy or hypersensitivity to warfarin.