PK time points were not being met as expected. Determination that risks outweighed benefit.

Primary Objective To determine if colestipol hydrochloride tablets can accelerate the elimination of teriflunomide. Teriflunomide will be administered for 14 days followed by colestipol dosing of 11 days. Total duration of the study is 40 days.

Secondary Objectives To collect information on the pattern of side effects with use of colestipol hydrochloride after teriflunomide administration and to determine the best duration of therapy needed for adequate elimination

participants will be followed for 40 days to allow for time to administer a loading dose of teriflunomide and observe the elimination of that drug using colestipol hcl.

Inclusion Criteria:

To be eligible for entry into this study, candidates must meet all of the following eligibility criteria at the time of the baseline visit:

1. Participants having provided informed consent with signature on informed consent form: the informed consent process should be complete with full discussion of all requirements and possible risks.
2. Healthy volunteer*
3. Aged 18-45 years, inclusive
4. Body Mass Index of 18-29 kg/m2 (body weight of 40-85 kg for women and 50-95 kg for men) *Healthy volunteer is defined as free of concomitant medications and use of either treatment, as deemed by the Investigator, is not contraindicated with any past medical history of the participant.

Exclusion Criteria:

1. Current smoker or past history as smoker.

2. Unable to provide informed consent to participate in the study Such as a mental condition rendering the participant unable to understand the nature, scope, and possible consequences of the study

3. Participant unlikely to comply with protocol as determined by Investigator, eg, uncooperative attitude, inability to return for follow-up visits

4. Clinically relevant cardiovascular, hepatic, neurological, endocrine, or other major systemic disease making implementation of the protocol or interpretation of the study results difficult or that would put the participant at risk by participating in the study

5. Persistent significant or severe infection, either acute or chronic

6. Recent history of drug or alcohol abuse within that past 6 months (participants will be asked to refrain from alcohol and drug use during the course of the study)

7. Participant is the Investigator or any Sub-investigator, research assistant, pharmacist, study coordinator, other staff or relative thereof, directly involved in the conduct of the protocol

8. Prior use of any investigational drug in the preceding 6 months

9. Liver function impairment or persisting elevations (confirmed by retest) of alanine aminotransferase (ALT), aspartate aminotransferase (AST), or direct bilirubin greater than 2x the upper limit of normal range (ULN).

10. Pregnant or breast-feeding women or those who plan to become pregnant during the study

11. Women of childbearing potential not protected by effective contraceptive method of birth control and/or who are unwilling or unable to be tested for pregnancy.

12. Participants wishing to parent children (be a partner in the conception of a child) during the course of the trial.

13. Participants with significantly impaired bone marrow function or significant anemia, leukopenia, or thrombocytopenia (confirmed by retest):

    • Hematocrit < 35% and/or
    • Absolute white blood cell count < 3000 cells/mm3 (μL) and/or
    • Platelet count < 150 000 cells/mm3 (μL) and/or- Absolute neutrophil ≤ 1500 cells/mm3 (μL)

14. Any known history of severe preexisting constipation

15. History of swallowing disorder or difficulty swallowing

small number of subjects analyzed with some lost to followup