Inhaled Nitrite in Subjects With Pulmonary Hypertension

This is a single-center, open label phase II study to evaluate the effect of inhaled nitrite delivered in a dose escalation manner on the change in pulmonary vascular resistance (PVR) in subjects with pulmonary hypertension undergoing right heart catheterization.

A total of 50 subjects with a confirmed diagnosis of pulmonary hypertension and meet all inclusion/exclusion criteria will be enrolled in the study which will entail a single right heart catheterization and nebulized nitrite dose of 45mg with one subsequent dosage of 90 mg.

Screening Visit:Initial screening evaluations including physical examination, medical history, and clinical laboratory assessments will be conducted to determine study eligibilities during a routine clinic visit at the UPMC HVI, CLC or inpatient at UPMC Presbyterian. Subjects who meet the inclusion criteria and none of the exclusion criteria will be entered into the study.

Day 1: This study visit will occur on the same day subjects are scheduled for their clinically indicated right heart catheterization or who volunteer for a research right heart catheterization for this specific study. Subjects on oral background PAH therapy (ETRA or PDE5I) will be instructed to hold their regimen on the day of the study visit.

Subjects will receive nebulized AIR001 doses escalated based upon safety and tolerability. The dose of inhaled nitrite will be delivered via electronic nebulizer. During the study right heart/pulmonary artery hemodynamics will be measured as well as noninvasive systemic blood pressure monitoring. Subjects will be tested for the changes in pulmonary vascular resistance (PVR) using standard clinical protocol hemodynamic recordings of right atrial, right ventricular, and pulmonary artery pressures, in addition to cardiac output at time zero,

3 Day phone follow up

30 Day follow up visit: All subjects enrolled in the study will be followed for 30 days (+/- 5 day window) after completion of the study treatment. A physical exam and clinical labs will be obtained at this visit.

Eligibility Criteria:
Inclusion Criteria:

Diagnosis of RHC confirmed WHO Group I PAH n=20

Idiopathic, primary or familial pulmonary arterial hypertension PAH associated with one of the following connective tissue diseases:

PAH associated with exposure to drugs and toxins eg, anorexigens, L-tryptophan, toxic rapeseed oil Stable PAH for at least 3 months if on therapy This patient population is closed to enrollment. Target enrollment of 20 subjects has been met

WHO Group II Pulmonary Hypertension n=20 Pulmonary capillary wedge pressure PWCP greater than 15 AND Transpulmonary Gradient TPG greater than12

WHO Group III PH n = 10

* Has WHO functional class II through IV symptoms
* Had the diagnosis of PH confirmed by a cardiac catheterization Both WHO Group I PAH and WHO Group III PH

WHO GROUP I PAH, II and III PH Age 18 and older Able to participate in right heart catheterization Evidence of a personally signed and dated informed consent document indicating that the subject has been informed of all pertinent aspects of the study Subjects who are willing and able to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures

Exclusion Criteria

Age less than 18 years

Baseline systemic hypotension, defined as MAP less than 50 mmHg

Required intravenous inotropes within 30 days prior to study participation;

Has uncontrolled systemic hypertension as evidenced by sitting systolic blood pressure greater than160 mm Hg or sitting diastolic blood pressure greater than100 mm Hg at screening

Has a history of portal hypertension or chronic liver disease, including hepatitis B and/or hepatitis C with evidence of recent infection and/or active virus replication defined as moderate to severe hepatic impairment Child-Pugh Class B-C

Has chronic renal insufficiency as defined by serum creatinine greater than 2.5 mgdL at screening or requires dialytic support

Has a hemoglobin concentration less than 9 gdL at Screening

History of atrial septostomy within 6 months prior to Day 1 visit

Repaired or unrepaired congenital heart disease CHD

Pericardial constriction

Confirmed diagnosis of restrictive or congestive cardiomyopathy;

Left ventricular ejection fraction 40 percent by multiple gated acquisition scan MUGA, angiography or echocardiography

Symptomatic coronary disease with demonstrable ischemia;

Other severe acute or chronic medical or laboratory abnormality that may increase the risk associated with study participation or investigational product administration or may interfere with the interpretation of study results and, in the judgment of the investigator, would make the subject inappropriate for entry into this study

Has a psychiatric, addictive or other disorder that compromises the ability to give informed consent for participating in this study. This includes subjects with a recent history of abusing alcohol or illicit drugs 30 days prior to study screening Day 0and for the duration of the study

Poorly controlled asthma defined by active wheezing and or cough with FEV1 less than 70 percent predicted, responsive to inhaled BD greater than 15 percent increase in FEV1 with BD

Investigators, study staff or their immediate families

Clinically significant intercurrent illness (including lower respiratory tract infection) or clinically significant surgery within 4 weeks before the administration of study drug

Personal or family history of congenital or acquired methemoglobinemia

Personal or family history of RBC CYP B5 reductase deficiency

Known or suspected hypersensitivity or allergic reaction to sodium nitrite Personal history of glucose-6-phosphate dehydrogenase G6PD deficiency or any contraindication to receiving methylene blue

If female, is pregnant or breast feeding, or has a positive pregnancy test result predose

Receipt of an investigational product or device, or participation in a drug research study within a period of 15 days or 5 half-lives of the drug, whichever is longer before the first dose of study drug

Blood loss or blood donation greater than 550 mL within 90 days or plasma donation greater than 500 mL within 14 days before administration of study drug

RHC less than 2 weeks from treatment visit unless clinically indicated