The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. The head-up tilt table test in this study was conducted 1 hour after administration of the study medication. The endpoint was a confirmed report of a near-syncopal symptom(s) (of sufficient severity that caused the patient to ask that the tilt table be returned to the horizontal position). Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set (FAS), defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. The head-up tilt table test in this study was conducted 1 hour after administration of the study medication. The endpoint was a confirmed report of a near-syncopal symptom(s) (of sufficient severity that caused the patient to ask that the tilt table be returned to the horizontal position). Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Per-protocol set, defined as participants in the Full Analysis Set who completed the study and were protocol compliant.

The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. The head-up tilt table test in this study was conducted 1 hour after administration of the study medication. The endpoint was a confirmed report of a near- syncopal symptom(s) (of sufficient severity that caused the patient to ask that the tilt table be returned to the horizontal position). Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out. In this outcome measure, the data analyzed are the same as for Outcome Measure 4 but the summary data are presented as least squares mean (standard error).

The Per-protocol set, defined as participants in the Full Analysis Set who completed the study and were protocol compliant.

The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. The head-up tilt table test in this study was conducted 1 hour after administration of the study medication. The endpoint was a confirmed report of a near-syncopal symptom(s) (of sufficient severity that caused the patient to ask that the tilt table be returned to the horizontal position). Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

Duration of effect was defined as the difference in time to onset of near-syncopal symptoms between the first and second tilt table test, conducted at 1 hour and 3 hours post-dose, respectively, at Treatment Visit 2 (time to onset at 3 hours minus time at 1 hour). The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. The endpoint was a confirmed report of a near-syncopal symptom(s) (of sufficient severity that caused the patient to ask that the tilt table be returned to the horizontal position). Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

The OHSA measures the severity of six symptoms/symptom complexes associated with orthostatic hypotension. Subjects rated symptoms experienced during the tilt table test on an eleven-point scale from "none" to "worst possible". The OHSA total score is the sum of six subscales, ranging from 0 (no symptoms) to 60 (worst possible symptoms). The OHSA was completed after the tilt table test was over, but was answered with reference to symptoms experienced during testing. The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

The OHSA measures the severity of six symptoms/symptom complexes associated with OH: dizziness, lightheadedness, and feeling faint; problems with vision; weakness; fatigue; trouble concentrating; and head/neck discomfort. Subjects rated symptoms experienced during the tilt table test on an eleven-point scale from "none" to "worst possible". Scores for each subscale range from 0 (no symptoms) to 10 (worst possible symptoms). The OHSA was completed after the tilt table test was over, but was answered with reference to symptoms experienced during testing. The tilt table test is a 10-minute assessment performed using a tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured with straps to prevent injury. After an equilibration period with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over 30 seconds. Symptoms of near syncope were defined as dizziness, lightheadedness, and feeling faint.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

The CGI-I instrument assesses the overall impression of the subject's orthostatic hypotension during the tilt table test by using a 7-point scale, with 1 being Very much improved; 2, Much improved; 3, Slightly improved; 4, No change; 5, Slightly worse; 6, Much worse; and 7, Very much worse. The clinician completed the CGI-I after each of the tilt table tests. A patient was assessed as "Improved" if the score was 1, 2, or 3. The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

The CGI-I instrument assesses the overall impression of the subject's orthostatic hypotension during the tilt table test by using a 7-point scale, with 1 being Very much improved; 2, Much improved; 3, Slightly improved; 4, No change; 5, Slightly worse; 6, Much worse; and 7, Very much worse. The patient completed the CGI-I after each of the tilt table tests. A patient was assessed as "Improved" if the score was 1, 2, or 3. The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

Blood pressure was recorded just before tilt table testing and immediately after. Timed readings were stopped once a subject experienced near-syncopal symptoms, except for subjects for whom the table was returned to horizontal before 1 minute; for these subjects, a reading was made at 1 minute and was included in analyses. The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

Blood pressure was recorded just before tilt table testing, at each minute during tilt table testing, and immediately after. Timed readings were stopped once a subject experienced near-syncopal symptoms, except for subjects for whom the table was returned to horizontal before 1 minute; for these subjects, a reading was made at 1 minute and was included in analyses. The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. The head-up tilt table test in this study was conducted 1 hour after administration of the study medication. The endpoint was a confirmed report of a near- syncopal symptom(s) (of sufficient severity that caused the patient to ask that the tilt table be returned to the horizontal position). Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out. In this outcome measure, the data analyzed are the same as for Outcome Measure 1 but the summary data are presented as least squares mean (standard error).

The FAS, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

Blood pressure was recorded just before tilt table testing, at each minute during tilt table testing, and immediately after. Timed readings were stopped once a subject experienced near-syncopal symptoms, except for subjects for whom the table was returned to horizontal before 1 minute; for these subjects, a reading was made at 1 minute and was included in analyses. The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

Heart rate was recorded just before tilt table testing, at each minute during tilt table testing, and immediately after. Timed readings were stopped once a subject experienced near-syncopal symptoms, except for subjects for whom the table was returned to horizontal before 1 minute; for these subjects, a reading was made at 1 minute and was included in analyses. The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

For hematology, blood samples (5.0mL) were taken at screening, study admission (if greater than 14 days since screening) and discharge/early termination. The following parameters were assessed: hemoglobin, hematocrit, red blood cells (RBC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), white blood cell count - total and differential (WBC), and platelet count. A shift in reference to normal was either lower or higher at discharge.

The Safety population, defined as all subjects who received at least one dose of investigational product.

For biochemistry, blood samples (10.0mL) were taken at screening, admission (if greater than 14 days since screening) and discharge/early termination. The following parameters were assessed: sodium, potassium, calcium, blood urea nitrogen (BUN)/Urea, creatinine, albumin, total protein and albumin/globulin (A/G) ratio, globulin, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), total bilirubin, glucose, chloride, and creatine kinase. A shift in reference to normal was either lower or higher at discharge.

The Safety population, defined as all subjects who received at least one dose of investigational product.

The tilt table test is a 10-minute assessment performed using a manual or automated tilt table in a specialized laboratory. Subjects were moved onto the horizontal table and secured to the table with straps to prevent injury. After an equilibration period of at least 10 minutes with the subject at rest, the test began and the head of the tilt table was elevated to a 70-degree angle over a period of up to 30 seconds. The head-up tilt table test in this study was conducted 1 hour after administration of the study medication. The endpoint was a confirmed report of a near-syncopal symptom(s) (of sufficient severity that caused the patient to ask that the tilt table be returned to the horizontal position). Symptoms of near syncope were defined as dizziness, lightheadedness, feeling faint, or feeling like the subject might black out. The Koch procedure is a 3-step process to analyze results while utilizing the available information on magnitude of differences.

The Full Analysis Set, defined as subjects who were randomized, received at least one dose of study drug, and had at least one measurement of time to syncope during tilt table testing.

For urinalysis, samples were taken at screening, study admission (if greater than 14 days since screening) and discharge/early termination): glucose, blood, protein, pH, specific gravity, leukocyte esterase, and microscopic examination. A shift in reference to normal was higher at discharge.

The Safety population, defined as all subjects who received at least one dose of investigational product.