And Treatment Of Pulmonary Hypertension ACC Rockies March 11-14, - PowerPoint PPT Presentation

Ottawa Hospital Research Institute Institute de recherche de l’Hopital d’Ottawa Update On Current Concepts And Treatment Of Pulmonary Hypertension ACC Rockies March 11-14, 2012 Dr. Duncan J. Stewart, CEO and Scientific Director, Ottawa Hospital Research Institute, VP Research, The Ottawa Hospital, Professor of Medicine, uOttawa

Sprott Stem Cell Centre Financial Interest Disclosure (over the past 24 months) Company Speaker Advisory Research Northern √ Therapeutics United √ √ Therapeutics Lung Rx √ √

Sprott Stem Cell Centre Learning objectives • Review the current approach to the work up and management of PAH • Provide an update on new concepts in the pathogenesis of pulmonary vascular disease • Introduce some of the next generation therapies based on new insight into the mechanisms underlying PAH

Sprott Stem Cell Centre Clinical Classification of Pulmonary Hypertension (Dana Point Classification 2008) Group 1 PAH Group 1 ’ PVOD and/or Group 5 Group 2 PCH PH with Unclear PH due to Multifactorial Left Heart Mechanisms Disease Group 4 Group 3 Chronic Thromboembolic PH due to Pulmonary Lung Diseases Hypertension and/or Hypoxia (CTEPH) Simonneau G, et al. J Am Coll of Cardiol. 2009;54:Suppl S43-54.

Sprott Stem Cell Centre Hemodynamic Definition of PAH Mean pulmonary arterial pressure of ≥ 25 mmHg at rest + Pulmonary capillary wedge pressure of < 15 mmHg + Pulmonary vascular resistance of > 3 mmHg/L/min (Wood units) European Society of Cardiology Guidelines. European Heart Journal. 2004;25:2243-78; Canadian Cardiovascular Society and Canadian Thoracic Society PAH Position Statement. Can J Cardiol. 2005;21:909-14

Sprott Stem Cell Centre Group 1: PAH PAH • Idiopathic PAH (primary) Fenfluramine Amphetamines • Heritable PAH ( Bmpr2 mutation) Cocaine • Drug- and toxin-induced St. John ’ s wort • Persistent PH of newborn SSRI Phenylpropanolamine • Associated with: Toxic rapseed oil • Connective tissue disease • HIV infection • Portal hypertension • Congenital heart disease • Schistosomiasis • Chronic hemolytic anemia Group 1 ‘ – Pulmonary Veno-occlusive Disease and/or Pulmonary Capillary Hemangiomatosis Simonneau G, et al. J Am Coll Cardiol. 2004;43:S5-12. Simonneau G, et al. J Am Coll of Cardiol. 2009;54:Suppl S43-54.

Sprott Stem Cell Centre Treatment Algorithm for Symptomatic PAH General Treatment Measures 1 Cardiac Acute Vasoreactivity • anticoagulant, diuretic, oxygen, digoxin catheterization Testing - ↓ mPAP > 10 mmHg No Yes - Final mPAP < 40 mmHg - Normal or a high CO • No Improvement Treatment with PAH-Specific Medications Oral • Deterioration (Chosen Based on Patient Functional Class) CCB 3 FC II FC III FC IV Sustained Combination Bosentan 4 [A] Epoprostenol [A] Response? Therapy? Sildenafil [A] Sildenafil 4 [A] Bosentan 2 [B] Epoprostenol [A] Treprostinil [C] Treprostinil [B/C] No Yes lung transplantation Careful monitoring of response is necessary Continue 1 Should be considered for all PAH patients 2 Limited data for WHO/NYHA Class IV 3 No calcium channel blocker has an indication for PAH approved in Canada Adapted from Badesch DB, et al. Chest. 2007;131(6):1917-28.

Sprott Stem Cell Centre A meta-analysis of trials of pulmonary hypertension: A clinical condition looking for drugs and research methodology Alejandro Macchia, Roberto Marchioli, RosaMaria Marfisi, Marco Scarano, Giacomo Levantesi, Luigi Tavazzi, Gianni Tognoni survival Prostaglandins Endothelin Receptor Antagonists Posphodiesterase inhibitors American Heart Journal, Volume 153, Issue 6, June 2007, Pages 1037-1047

Sprott Stem Cell Centre Functional “pruning” of the lung micro - vasculature in Pulmonary Hypertension Normal Pulmonary Hypertension How? MR perfusion images courtesy of Evangelos Michelakis, Edmonton, Alberta

Sprott Stem Cell Centre Characteristic pathology of PAH • SMC hypertrophy – Primary or secondary – Role of endothelial injury/dysfunction? • Intimal hyperplasia – Not found in most animal models – Likely an important mechanism of occlusive remodeling Plexiform lesions – hallmark lesion of PAH

Sprott Stem Cell Centre What is the “root - cause” of PAH? • Several distinct processes have been implicated – Proliferative • Increased vascular cell growth  arteriolar obliteration/occlusion – Inflammatory • Innate and adaptive  local tissue damage and recruitment of circulating inflammatory/stem cells – Degenerative • EC injury/apoptosis  loss of functional arterioles (pruning) • Not separate or mutually exclusive

Sprott Stem Cell Centre The Hypoxia-SU5416 Model of Severe PAH is Dependent on EC Apoptosis Activated Effect of VEGF receptor caspase 3 antagonist (SU5416) PCNA Effects of SU5416 reversed by z-ASP Taraseviciene-Stewart et al. FASEB J. 15:427,2001

Sprott Stem Cell Centre Complex vascular lesions up to 14 wks in the rat hypoxia-SU5416 model Lung vascular EC apoptosis is a trigger for PAH leading to reactive vascular cell proliferation and inflammation Abe at al. Circulation . 2010;121:2747-2754

Sprott Stem Cell Centre New insight into the pathogenesis of PAH from the genetics of Familial PAH • 6 – 12% of cases of PPH familial, autosomal dom. • PPH gene identified (Nat Gen 26:81,2000) • BMPR2 “loss -of- function” mutations – TGF- b receptor superfamily – ~60% of familial and 25% of sporadic PAH Bone Morphogenetic Protein Receptor 2

Sprott Stem Cell Centre BMPs inhibit growth and induce apoptosis of human PA SMCs Loss of function Zhang S, AmJ Physiol Lung Cell Mol Physiol, 2003

Sprott Stem Cell Centre Effect of BMP-2 on TNF a -induced endothelial cell apoptosis (TUNEL) TNF 10.0 TUNEL Positive Nuclei (%) * 8.0 6.0 † 4.0 TNF+BMP 2.0 0.0 TNF TNF+BMP Circulation Research 2005

Sprott Stem Cell Centre BMPRII gene silencing by siRNA siRNA siRNA RNAiFect Control Silencing NS b c * 4 Fold-increase in Apoptosis 3 2 siRNA Control Silencing 1 BMPRII 115kDa Increased susceptibility for EC apoptosis is a key 0 mechanism by which Bmpr2 mutations lead to PAH siRNA siRNA β -actin 40 kDa NS Silencing Circulation Research 2005

Sprott Stem Cell Centre Delivery of early-growth EPCs in the rat monocrotaline (MCT) model Pre-capillary arteriole Pulmonary arteriole 15 minutes 1 week post MCT Zhao et al. Circ Res. 2005; 96(4):442-50

Sprott Stem Cell Centre Effect of EPCs on PAH in the mono- crotaline (MCT) “prevention’ model of PAH Control RVSP (mmHg) MCT-FB MCT-EPC * 60 FMA SMA * 50 † 40 30 20 10 0 Con MCT FB EPC Zhao et al. Circ Res. 2005; 96(4):442-50

Sprott Stem Cell Centre Effect of EPCs in the reversal of MCT- induced PAH (RVSP) * p<0.01 vs. d21 MCT 80 * ** p<0.001 vs. d21 MCT Day 21 RVSP (mmHg) 60 Day 35 40 ** 20 0 EPCs/ Control EPCs MCT eNOS Zhao et al. Circ Res. 2005; 96(4):442-50

Sprott Stem Cell Centre Survival analysis following cell therapy in the treatment MCT-PAH model N = 63 1.0 0.9 Cumulative Survival MCT-CAC/eNOS 0.8 0. MCT-CAC 7 P<0.02 0. 6 P<0.05 0.5 MCT 0.4 0.3 25 27 29 31 33 35 Days post MCT Zhao et al. Circ Res. 2005; 96(4):442-50

Sprott Stem Cell Centre Pulmonary Hypertension And Cell Therapy (PHACeT) Trial Safety study – I o EP: tolerability of cell transplantation in patients with PAH refractory to all standard therapies Cell delivery – eNOS transfected autologous early growth EPCs – Delivery via SG catheter • Pacing port (i.e. RV delivery) – allows continuous monitoring of PA pressure – Dose ranging for eNOS transfected cells given over 3 days in divided doses

Sprott Stem Cell Centre PHACeT Trial Cell Processing Transfection with eNOS Viability: >98% 2.5 x10 6 heNOS-Tx EPCs/ml

Sprott Stem Cell Centre Overlapping, dose escalation protocol = 50 million 20x10 6 20x10 6 cells Panel 3 Day 3 10x10 6 = 23 million 10x10 6 10x10 6 Panel 2 cells 3x10 6 = 7 million 3x10 6 3x10 6 cells 1x10 6 Panel 1 3 patients/panel 3 additional pts at highest Day 1 Day 2 Day 3 panel

Sprott Stem Cell Centre Hemodynamic Data – n=7 P=0.05 1600 1400 TPVR (dyne*s*cm-5) 1200 1160 1000 ~ ↓ 400 dyne*s*cm -5 800 781 600 Pre cell delivery 400 30’ post cell delivery 200 0 1 2 3 Days NO-mediated effect of eNOS transfected cells?

Sprott Stem Cell Centre Inhibition of breakdown of cGMP enhances NO action

Sprott Stem Cell Centre Hemodynamic Data Interaction with PDEV inhibitor No Sildenafil (n=3) On Sildenafil (n=4) 120 120 100 100 TPVR (% change) ~20% ~40% 80 80 60 60 40 40 20 20 0 0 1 2 3 1 2 3 Days Days

Sprott Stem Cell Centre Six minute walk distance 100 90 Change in 6MW (meters) 80 70 60 50 70 40 * 30 Change 6MW (meters) 60 20 10 50 0 1M 2M 3M 40 100 90 30 Change 6MW (meters) 80 70 20 60 50 10 40 0 30 Consistent with our preclinical data supporting the 20 1M 2M 3M 10 importance eNOS-enhanced cell therapy in the * P<0.01 0 1M 2M 3M reversal of established PAH