Business reasons

A pilot study of subjects with refractory hypertension (on 3 concomitant agents with SBP > 140 mmHg and a DBP > 90 mmHg) randomized in a double-blind fashion to receive 4 single escalating doses of study medication in clinic.

12 subjects with refractory hypertension will be randomized in a double-blind fashion to receive single escalating doses of study medication in-clinic: on Day 1 (1mg), Day 8 (2mg), Day 15 (4mg) and Day 22 (8mg). On each of these 4 days, 10 subjects will receive TC-5214, and 2 subjects will receive placebo. Placebo treatments will be pooled across the 4 days of single-dose to produce an equivalent reference cohort (n = 8) for each treatment dose (n=10). Following the single-dose administration of 8mg in the clinic on Day 22, subjects will continue with two weeks (Days 23 - 35) of outpatient self-administration of TC-5214 (4mg BID; n = 6), or matching placebo (BID; n = 6). On Day 36, subjects will return for a final in-clinic dose of either TC-5214 (4mg, n = 6) or placebo (n = 6). There will be a 1-week follow-up period at the end of the treatment period.

Inclusion Criteria:

1. Refractory hypertension, defined as a SBP of >140mmHg and a DBP > 90mmHg, on stable doses of at least 3 concomitant antihypertensive treatment (which must include a diuretic and an ACEI, ARB or RA) for 8 weeks prior to Screening. All approved antihypertensive treatments are allowed except for alpha-adrenergic blockers, hydralazine, clonidine, guanethidine, guanadrel, and rauwolfia alkaloids.
2. Stable hypertension, as defined by: a. mean SBP on Day -7 that is within 20mmHg of the mean SBP on Day 1, with both mean SBPs > 140mmHg; and b. mean DBP on Day -7 that is within 10mm of the mean DBP on Day 1, with both mean DBPs > 90mmHg.
3. Outpatient with stable housing.
4. Subjects must be able to stay in the clinic for 8 hrs on Day 1, Day 8, Day 15, Day 22, and Day 36.
5. Able to give and to sign informed consent.

Exclusion Criteria:

1. Any unstable medical condition other than hypertension;
2. Stage 3 hypertension (SBP > 180mmHg and/or DBP > 110mmHg);
3. Heart rate > 100 beats per minute;
4. WOCBP who is pregnant or who is planning to become pregnant during the study;
5. History within past year of alcohol or illicit drug abuse;
6. Unable to comply with study procedures in opinion of investigator;
7. Concomitant medications for any medical condition that is uncontrolled for more than 2 weeks prior to study entry;
8. Current use of alpha-adrenergic blocker, hydralazine, clonidine, guanethidine, guanadrel, or rauwolfia alkaloids;
9. History of myocardial infarction or angina pectoris;
10. Current seizure disorder;
11. Renal insufficiency as defined by a serum creatinine > 2.0;
12. Uncontrolled hypothyroidism, vitamin B12 or folic acid deficiency;
13. History of or concurrent ileus, glaucoma, or urinary retention;
14. Inability of subject to understand and sign the ICF;
15. Known systemic infection (HBV, HCV, HIV, TB);
16. Current use of smoking cessation therapy within 4 weeks of screening;
17. Use of herbal supplements;
18. Clinically significant finding on physical exam;
19. Clinically significant laboratory or ECG abnormality, including QTcF > 460 msec;
20. Participation in another clinical trial in last month;
21. Body Mass Index (BMI) > 35.
22. Body weight < 100 pounds.
23. Site staff or family member of study site staff.