A Study to Evaluate the Efficacy, Safety and Tolerability of PDNO Infusion in Patients With Pulmonary Hypertension After Cardiopulmonary Bypass Surgery

An Open-Label, Multicenter Study To Evaluate the Dose, Efficacy, Safety and Tolerability of PDNO (Nitrosooxypropanol) Infusion in Patients With Pulmonary Hypertension After Cardiopulmonary Bypass (CPB) Surgery for Coronary Artery Bypass Grafting (CABG) or Mitral or Aortic Valve Repair or Replacement With or Without CABG

This is an open-label, multicenter study evaluating the dose, effect, safety and tolerability of intravenous PDNO infusion given to patients undergoing cardiopulmonary bypass (CPB) surgery with post-operative acute pulmonary hypertension (aPH).

Study Overview

• Status: Recruiting
• Conditions: Pulmonary Hypertension
• Intervention / Treatment: Drug: Sodium chloride (placebo); Drug: PDNO

• Study Type: Interventional
• Enrollment (Estimated): 12
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Christofer Adding, MD/PhD; Phone Number: +46 (0) 70 788 67 66; Email: christofer.adding@attgeno.com

Study Locations

• Sweden
  • Gothenburg, Sweden, SE-413 45
    • Recruiting
    • Sahlgrenska University Hospital, Anaesthesiology and Intensive Care
    • Contact: Sven-Erik Ricksten, MD
  • Örebro, Sweden, SE-701 85
    • Recruiting
    • Örebro University Hospital, Vascular and Thoracic Department (Kärl-Thoraxkliniken)
    • Contact: Jenny Seilitz, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Ability to understand and willing to sign an informed consent form (ICF)
• Male and female patients, age ≥ 18 years
• Planned to undergo elective cardiopulmonary bypass (CPB) for coronary artery bypass grafting (CABG), aortic valve repair (AVR) or mitral valve repair (MVR) with or without CABG
• Diagnosed with echocardiographic signs of pulmonary artery systolic pressure (PASP) >50 mmHg , as estimated by doppler defined echocardiography using a modified Bernoulli equation: PASP ≈ 4 (tricuspid regurgitant jet velocity)^2 + central venous pressure (CVP)

Exclusion Criteria:

• History of chronic pulmonary hypertension (PH) (WHO group 1, 3, 4 or 5), not group 2 due to left heart disease
• Patients with contraindications for pulmonary artery catheter (PAC)
• History of severe chronic obstructive pulmonary disease
• Left heart failure with ejection fraction (EF) <35%
• Non-ST elevation myocardial infarction (non-STEMI) or ST elevation myocardial infarction (STEMI) within 1 months prior to informed consent
• Stroke (cerebrovascular lesion [CVL]), transient ischemic attack (TIA), AV block III within 3 months prior to informed consent or QTcF >450ms at the time of screening
• High inotropic requirement (no more than one inotrope treatment and the vasopressor norepinephrine at time of screening/postoperative evaluation)
• (Increased) mediastinal bleeding >100 mL/hour in mediastinal drainage at postoperative evaluation
• Mechanical circulatory assistance (intra aortic balloon pump [IABP] or right/left-ventricular assist device [R/L VAD])
• Echocardiographic evidence of significant tricuspid insufficiency
• Body Mass Index (BMI) >40 kg/m^2
• Estimated glomerular filtration rate (eGFR) < 30 mL/min preoperative value
• Methemoglobin >3%
• Indication of liver disease, defined by serum levels of either alanine aminotransferase (ALT), aspartate aminotransferase (AST) or alkaline phosphatase (ALP) above 3 x upper limit of normal (ULN) (preoperative value)
• Preoperative haemoglobin <10 g/dL, postoperative: Hb < 9 g/dL
• Thrombocytopenia (platelet count <100,000/mm^3), preoperative value
• Prothrombin time International ratio (INR) > 1.3, preoperative value
• Pregnant or lactating women, or with a positive pregnancy test at screening (for fertile women only)
• Ongoing daily treatment the last 3 days with non-steroidal anti-inflammatory drugs (NSAIDs, excluding low dose, i.e. 75 mg, acetylsalicylic acid), new oral anticoagulants (NOACs), warfarin, heparin, clopidogrel (last 5 days). Low molecular weight heparin (LMWH) is not an exclusion criterion. Any use of PDE5 inhibitors (sildenafil, tadalafil, vardenafil and avanafil) within 48 hours prior to the administration of PDNO.
• Known active malignancy within the past 3 years except for localized prostate cancer, cervical carcinoma in situ, breast cancer in situ, or nonmelanoma skin cancer that has been definitively treated
• History of allergy/hypersensitivity to PD or ongoing allergy/hypersensitivity or history of hypersensitivity to drugs with a similar chemical structure or class to PDNO
• History of any other clinically significant disease or disorder
• Participation in any interventional clinical study or has been treated with any investigational research products within 30 days or 5 half-lives, whichever is longer, prior to the initiation of screening

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Treatment with PDNO (placebo during baseline and washout observation periods before & after PDNO); PDNO will be administered as an incremental intravenous infusion of respectively 15 minutes with the planned dosage: 3, 10, 30, 45 and 60 nmol/kg/min. If no effect on MPAP/PVR is seen at 60 nmol/kg/min in the first patients treated, further dose escalation up to 120 nmol/kg/min is possible, if recommended by the Internal Safety Review Committe (iSRC) following careful review of collected safety data. The iSRC will in any case review all collected data after 4, 8 and 12 patients (if applicable also after 16 and 20 patients). PDNO is administered together with a carrier buffer (NaHCO3-) flow into a central venous catheter. Placebo (NaCl, commercially available dilution solution for parenteral use, 9 mg/mL) will be administered during the baseline and washout observation periods before and after start of IMP infusion.

Drug: Sodium chloride (placebo); Placebo (NaCl, commercially available dilution solution for parenteral use, 9 mg/mL); Other Names: NaCl; Drug: PDNO; PDNO consists of propylene glycol (1,2-propanediol, PD) chemically combined with NO (to be donated). The drug substance is formulated as an inherent mixture of 4 structure analogues. The mixture consists of an equilibrium of the 2 regioisomers 1-(nitrosooxy) propan-2-ol and 2-(nitrosooxy) propan-1-ol. In addition, each regioisomer is a racemic mixture.; Other Names: Nitrosooxypropanol

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean change in pulmonary vascular resistance (PVR)	PVR, will be derived as the mean pulmonary artery pressure (MPAP) - pulmonary capillary wedge pressure (PCWP) divided by cardiac output (CO), (PVR=(MPAP-PCWP)/CO), as measured with a pulmonary artery catheter (PAC) including thermodilution-determined cardiac output. Assessments will be done at the following timepoints: T0 (-15 minutes) and T1 (0 minutes) with placebo; T2 (15 minutes), T3 (30 minutes), T4 (45 minutes), T5 (60 minutes), and T6 (75 minutes) with 3, 10, 30, 45, 60 nmol/kg/min with PDNO, respectively; and T7 (85 minutes) and T8 (95 minutes) with placebo.	From baseline (mean of -15 minutes and 0 minutes) to time point 15, 30, 45, 60, and 75 minutes with PDNO, respectively; and 85 and 95 minutes with placebo.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean change in the pulmonary vascular resistance/systemic vascular resistance ratio (PVR/SVR ratio)	PVR, will be derived as the mean pulmonary artery pressure (MPAP) - pulmonary capillary wedge pressure (PCWP) divided by cardiac output (CO), (PVR=(MPAP-PCWP)/CO), as measured with a pulmonary artery catheter (PAC) including thermodilution-determined cardiac output. SVR is determined from mean pulmonary artery pressure - central venous pressure divided by cardiac output (CO), (SVR=(MABP-CVP)/CO). Assessments will be done at the following timepoints: T0 (-15 minutes) and T1 (0 minutes) with placebo; T2 (15 minutes), T3 (30 minutes), T4 (45 minutes), T5 (60 minutes), and T6 (75 minutes) with 3, 10, 30, 45, 60 nmol/kg/min with PDNO, respectively; and T7 (85 minutes) and T8 (95 minutes) with placebo.	From baseline (mean of -15 minutes and 0 minutes) to time point 15, 30, 45, 60, and 75 minutes with PDNO, respectively; and 85 and 95 minutes with placebo.
Mean change in fractional area change (FAC)	Assessments will be done at the following timepoints: T0 (-15 minutes) and T1 (0 minutes) with placebo; T2 (15 minutes), T3 (30 minutes), T4 (45 minutes), T5 (60 minutes), and T6 (75 minutes) with 3, 10, 30, 45, 60 nmol/kg/min with PDNO, respectively; and T7 (85 minutes) and T8 (95 minutes) with placebo.	From baseline (mean of -15 minutes and 0 minutes) to time point 15, 30, 45, 60, and 75 minutes with PDNO, respectively; and 85 and 95 minutes with placebo.
Mean change in tricuspidannular plane systolic excursion (TAPSE)	Assessments will be done at the following timepoints: T0 (-15 minutes) and T1 (0 minutes) with placebo; T2 (15 minutes), T3 (30 minutes), T4 (45 minutes), T5 (60 minutes), and T6 (75 minutes) with 3, 10, 30, 45, 60 nmol/kg/min with PDNO, respectively; and T7 (85 minutes) and T8 (95 minutes) with placebo.	From baseline (mean of -15 minutes and 0 minutes) to time point 15, 30, 45, 60, and 75 minutes with PDNO, respectively; and 85 and 95 minutes with placebo.
Mean change in right ventricular (RV) free wall strain	Assessments will be done at the following timepoints: T0 (-15 minutes) and T1 (0 minutes) with placebo; T2 (15 minutes), T3 (30 minutes), T4 (45 minutes), T5 (60 minutes), and T6 (75 minutes) with 3, 10, 30, 45, 60 nmol/kg/min with PDNO, respectively; and T7 (85 minutes) and T8 (95 minutes) with placebo.	From baseline (mean of -15 minutes and 0 minutes) to time point 15, 30, 45, 60, and 75 minutes with PDNO, respectively; and 85 and 95 minutes with placebo.
Safety and tolerability of PDNO in patients undergoing Cardiopulmonary Bypass (CPB) surgery	Measured by incidence of: treatment-emergent adverse events (AEs), treatment-emergent serious AEs (SAEs), treatment-emergent AEs of special interest (AESI), treatment-emergent changes in vital signs (blood pressure, pulse, oxygen saturation, respiratory frequency, body temperature), treatment-emergent electrocardiogram (ECG) abnormalities, and treatment-emergent laboratory abnormalities.	Until study end (i.e., end of Day 1 [95 minutes]). All AEs (including SAEs) will be collected from the initiation of any study specific procedure, starting when postoperative preparatory preparations are performed on Day 1 and until the end of the study.
Exposure parameters for 1,2-propanediol (PD): estimated area under the curve from time 0 to time t (AUC0-t)	To assess the exposure of PD.	Assessments at time points T0 (-15 minutes; placebo), T6 (75 minutes; PDNO), and T8 (95 minutes; placebo).
Exposure parameters for 1,2-propanediol (PD): estimated area under the curve from time 0 to infinity (AUC0-inf)	To assess the exposure of PD.	Assessments at time points T0 (-15 minutes; placebo), T6 (75 minutes; PDNO), and T8 (95 minutes; placebo).
Exposure parameters for 1,2-propanediol (PD): maximum plasma concentration (Cmax)	To assess the exposure of PD.	Assessments at time points T0 (-15 minutes; placebo), T6 (75 minutes; PDNO), and T8 (95 minutes; placebo).
Exposure parameters for 1,2-propanediol (PD): estimated elimination half life (t½)	To assess the exposure of PD.	Assessments at time points T0 (-15 minutes; placebo), T6 (75 minutes; PDNO), and T8 (95 minutes; placebo).

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assess the levels of the following biomarkers: nitrite and nitrate in plasma (µM)	Explore potential biomarkers.	Change from baseline T0 (-15 minutes; placebo) to time point T6 (75 minutes; PDNO).
Assess the levels of the following biomarkers: 1,2-propanediol (PD) metabolites in serum	Explore PD metabolites.	Change from baseline T0 (-15 minutes; placebo) to time point T6 (75 minutes; PDNO).

Collaborators and Investigators

• Sponsor: Attgeno AB
• Collaborators: Scandinavian CRO AB
• Investigators: Study Director: Cecilia Kemi, PhD, Attgeno AB

Study record dates

Study Major Dates

• Study Start (Actual): October 23, 2022
• Primary Completion (Estimated): December 31, 2023
• Study Completion (Estimated): December 31, 2023

Study Registration Dates

• First Submitted: December 19, 2022
• First Submitted That Met QC Criteria: January 17, 2023
• First Posted (Actual): January 26, 2023

Study Record Updates

• Last Update Posted (Actual): August 1, 2023
• Last Update Submitted That Met QC Criteria: July 31, 2023
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Keywords: Acute pulmonary hypertension
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Respiratory Tract Diseases; Lung Diseases; Hypertension; Hypertension, Pulmonary
• Other Study ID Numbers: 2021-PDNO-003; 2021-005032-30 (EudraCT Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No