Gossamer Bio, Inc. · NASDAQ:GOSS
Gossamer Bio — Q1 2025 Earnings Presentation
43 slides from Gossamer Bio's earnings presentation, May 15, 2025
Slide 1: Corporate Presentation
Corporate Presentation May 2025
Slide 2: Forward Looking Statements
Forward Looking Statements This presentation contains forward-looking statements. All statements other than statements of historical facts contained in this presentation, including statements regarding our future results of operations and financial position, business strategy, prospective products,
Slide 3: I. Overview of Seralutinib
I. Overview of Seralutinib A Novel Investigational Inhaled Treatment for Pulmonary Hypertension (PH)
Slide 4: Gossamer Bio Quick Facts
Gossamer Bio Quick Facts ✓ HQ in Focused on $ Positive Phase 2 San Diego, treating rare, fatal Proof of Concept ~$258 million cash(1) California lung diseases Study INVESTIGATIONAL COMMERCIAL PROGRAM CLASS INDICATION PHASE 1 PHASE 2 PHASE 3 RIGHTS (Route of Admin.) Partnered with Pulmonary Arterial
Slide 5: Seralutinib Overview
Seralutinib Overview A Novel Investigational Inhaled Treatment for PH • Inhaled kinase inhibitor, designed from scratch to address the underlying disease pathophysiology of pulmonary hypertension (PH) ➢ PH is a class of rare lung diseases including PAH and PH-ILD, amongst others • PAH Status: Ongoin
Slide 6: II. Seralutinib in PAH
II. Seralutinib in PAH
Slide 7: PAH is a Rare, Progressive & Fatal Disease
PAH is a Rare, Progressive & Fatal Disease • PAH is a rare, progressive cardiopulmonary disease, with no known cure, affects approximately 50,000 patients in the US1 • Characterized by high blood pressure in the blood vessels carrying deoxygenated blood from the right side of the heart to the lungs
Slide 8: Pulmonary Vascular Remodeling: A Key Structural Alteration in PAH
Pulmonary Vascular Remodeling: A Key Structural Alteration in PAH Pathological mechanisms Healthy Disease Inflammation Proliferation Fibrosis Vascular remodeling of the small pulmonary arteries • Peri-vascular inflammation Vascular lumen • Neointimal proliferation of endothelial cells and myofibrobl
Slide 9: Seralutinib: An Intentional Approach to PAH
Seralutinib: An Intentional Approach to PAH • Designed from scratch to address the underlying disease pathophysiology of pulmonary hypertension (PH) • Only tyrosine kinase inhibitor (TKI) intentionally developed as an inhaled treatment for PAH • Inhibiting the PDGFR pathway reverses pulmonary vascul
Slide 10: Vasodilatory Therapies
In a Treatment Paradigm Long-Dominated by Vasodilatory Therapies, Patients Need Treatments that Address the Underlying Disease Functional Class I II III IV Vasodilatory Therapies PDE-5i or sGC Generics Available RoA: Oral Top Sales in 2023: Adempas ($730 million, sGC Stimulator) ERAs FDA Approve
Slide 11: III. Phase 2 TORREY Study in PAH
III. Phase 2 TORREY Study in PAH
Slide 12: TORREY Study Phase 2 Topline Results (24 Weeks)
TORREY Study Phase 2 Topline Results (24 Weeks) • Met Primary Endpoint: Statistically significant reduction in PVR in heavily-treated study population • Consistent numerical PVR (primary endpoint) benefit seen in all 21 pre-specified subgroups in favor of seralutinib - enhanced benefit seen in patie
Slide 13: TORREY: Completed Phase 2 Study of Seralutinib in FC II and III PAH
TORREY: Completed Phase 2 Study of Seralutinib in Patients With Functional Class II and III PAH Randomization Screening Blinded, Placebo-Controlled Period Follow-up 24 weeks Seralutinib, n = 44 Placebo, n = 42 Patient Population Stable FC II & III PAH patients on background therapy, including double
Slide 14: Selected Baseline Disease Characteristics
Selected Baseline Disease Characteristics (ITT Population) • Baseline patient PAH disease characteristics were milder than precedent PAH clinical trial populations, in large part due to patient availability during the COVID pandemic, which was ongoing during enrollment • Despite this, seralutinib de
Slide 15: Seralutinib Phase 2 TORREY Study Scorecard
Seralutinib Phase 2 TORREY Study Scorecard Consistently Demonstrated Improvement across Multiple Meaningful Measures Up to 24 Weeks… Pre-Specified Measurement Stat. Sig. Endpoint Assessed Attribute Measure Procedure Improvement*? p-value Notes Citation • Demonstrated numerical improvement across all
Slide 16: Primary Endpoint: Change in PVR From Baseline to Week 24
Primary Endpoint: Change in PVR From Baseline to Week 24 Overall Population WHO Functional Class Breakout Pre-Specified Subgroup Analysis Frantz RP, et al. Lancet Respir Med 2024;12(7):523-534. Based on an ANCOVA model with multiple imputation. 16 ANCOVA, analysis of covariance; FC, functional class
Slide 17: Secondary Endpoint: Change in 6MWD from Baseline by Functional Class
Secondary Endpoint: Change in 6MWD from Baseline by Functional Class Overall Population WHO Functional Class III Pre-Specified Subgroup Frantz RP, et al. Lancet Respir Med 2024;12(7):523-534. ITT Population. Based on a MMRM model. 17 6MWD = six-minute walk distance; BL = baseline; FC, functional cla
Slide 18: Rapid and Sustained Reduction in NT-proBNP
Seralutinib Treatment Resulted in a Rapid and Sustained Reduction in NT-proBNP, a Biomarker of Right Heart Strain • Seralutinib treatment resulted in significant reduction in NT-proBNP vs placebo at Week 12 (-309.6 ng/L, p=0.0116) and Week 24 (-408.3 ng/L, p=0.0012). Frantz RP, et al. Lancet Respir
Slide 19: Centrally-Read RHC and ECHO Results Consistently Favored Seralutinib
Centrally-Read RHC and ECHO Results at Week 24 Consistently Favored Seralutinib (ANCOVA – Observed Cases) LS Mean Statistically Significant Result Point Estimate Favoring Endpoint p-value Difference (95% CI) Favoring Seralutinib (p ≤ 0.05) Seralutinib Right Atrium Area (cm2) -1.99 (-3.783, -0.206) 0
Slide 20: Incidence of TEAEs by Preferred Term: ≥ 5% in Seralutinib
Incidence of TEAEs by Preferred Term: ≥ 5% in Seralutinib (Safety Population) Placebo Seralutinib Preferred Terma (N=42) (N=44) Number of subjects with a TEAE 36 (85.7) 41 (93.2) Cough 16 (38.1) 19 (43.2) COVID-19 7 (16.7) 6 (13.6) Diarrhea 3 (7.1) 6 (13.6) Headache 8 (19.0) 6 (13.6) Dizziness 2 (4.
Slide 21: TORREY Phase 2 Imaging Sub-Study
TORREY Phase 2 Imaging Sub-Study: Assessing Pulmonary Vascular Remodeling in Patients Treated with Seralutinib • Purpose: Provide evidence consistent with a reverse remodeling effect of seralutinib • Hypothesis: volume of distal pulmonary arteries relative to volume of proximal pulmonary arteries wi
Slide 22: Pulmonary Vascular Volume of Small Distal Arterial Vessels is Decreased in PAH
Pulmonary Vascular Volume of Small Distal Arterial Vessels is Decreased in PAH, Leading to Dilation of Larger Proximal Vessels CT imaging can quantify these changes: BV5A: BVV of pulmonary arteries with a CSA < 5 mm 2 BV5-10A: BVV of pulmonary arteries with a CSA between 5-10 mm2 BV10A: BVV of pulmo
Slide 23: Seralutinib Treatment Increases the BV5A/BV10A Ratio
Seralutinib Treatment Increases the BV5A/BV10A Ratio & Supports Blood Volume Redistribution Hypothesis Seralutinib increases BV5A/BV10A ratio Change in BV5A/BV10A ratio from BL Parameter LSMD Estimate (95% CI) p-value to Week 24 correlates with change in hemodynamics BV5A/BV10A ratio 0.845 (0.105, 1
Slide 24: Examples of Imaging: Placebo vs. Seralutinib
Examples of Imaging: Placebo vs. Seralutinib Baseline Week 24 Baseline Week 24 Placebo patient Seralutinib patient Female, 24 y, iPAH, FC II, treated with PDE5-i + prostacyclin Female, 58 y, iPAH, FC II, treated with ERA + PDE5-i + prostacyclin PVR change, dyne*s/cm5 (%) 283 (+65.4) PVR change, dyne
Slide 25: PVR Continues to Improve With Seralutinib in the OLE
PVR Continues to Improve With Seralutinib in the OLE Double-blind (TORREY) Open-label extension Median PVR Values, dyne*s/cm5 Placebo/ Seralutinib/ Placebo- Cont.- Visit Crossed Seralutinib Baseline 650.0 620.0 -32 -56 -89 Week 24 647.0 505.0 -146 Week 72 603.0 475.0 Note: OLE study is ongoing. Week
Slide 26: 6MWD Increases in Continued-Seralutinib Group & Placebo-Crossed Group
6MWD Increases in Continued-Seralutinib Group & Placebo-Crossed Group Note: OLE study is ongoing. Week 48 and 72 data are reflective of the database as of March 4, 2024. 26 6MWD = six-minute walk distance; OLE = open-label extension; SE = standard error. Source: https://www.gossamerbio.com/wp-conten
Slide 27: III. PROSERA Phase 3 Study
III. PROSERA Phase 3 Study
Slide 28: Ongoing PROSERA Phase 3 Study
Ongoing PROSERA Phase 3 Study Phase 3 PROSERA Trial Design Baseline Characteristics: PROSERA Utilizes Enrichment Criteria to Guide Patient Enrollment Double Blind Placebo-Controlled Extended Double Blind Treatment (up to an additional 24 weeks) PROSERA Phase 3* TORREY Phase 2 Treatment Period (24 we
Slide 29: IV. The Next Frontier: PH-ILD
IV. The Next Frontier: PH-ILD
Slide 30: Seralutinib's Next Frontier: What is PH-ILD?
Seralutinib’s Next Frontier: What is PH-ILD? • WHO Group 3 PH is pulmonary hypertension associated with lung diseases and / or hypoxia • PH associated with interstitial lung disease (PH-ILD) is a ~60-100K PH-ILD subgroup of Group 3 PH patients in US(1) • PH-ILD includes PH related to idiopathic pulm
Slide 31: Planned SERANATA Phase 3 Study in PH-ILD
Planned SERANATA Phase 3 Study in PH-ILD Placebo-Controlled Treatment Period Long-Term Extension Period (24 Weeks) Placebo BID (n ≈ 160) Patients with Seralutinib 90 mg BID (n ≈ 160) Seralutinib 90 mg BID PH-ILD Seralutinib 120 mg BID (n ≈ 160) Seralutinib 120 mg BID Primary Endpoint (6MWD) Evaluate
Slide 32: Seralutinib MoA Aligned with Underlying Pathophysiology of Group 3 PH
Seralutinb MoA Aligned with Underlying Pathophysiology of Group 3 PH Disease Process Cell Type / Mechanism Potentially Relevant Pathway • CSF1R Vascular Inflammation Macrophages & ECs • KIT Vascular fibrosis Fibroblasts / myofibroblasts • PDGFR Pulmonary vasculopathy Endothelial-to-mesenchymal trans
Slide 33: PH-ILD Presents a Significant Market Opportunity
PH-ILD Presents a Significant Market Opportunity PAH PH-ILD US Prevalence ~30-50k1 ~60-100k+3 Competitive intensity 16 marketed products 1 marketed product 5-year survival rate 57%2 23%4 Generics 8 generic products 0 generic products Patients living with PH-ILD are deeply underserved 1. Kirson NY et
Slide 34: V. Milestones & Finances
V. Milestones & Finances
Slide 35: Milestones & Financial Overview
Milestones & Financial Overview Near Term Clinical Milestones • 4Q 2025: Activate First Clinical Sites for Phase 3 SERANATA Study in PH-ILD • February 2026: Topline Data from Ongoing Phase 3 PROSERA Study in PAH Financial Overview Cash, Cash Equivalents and Marketable Securities ~$258mm (As of 3/31/
Slide 36: Appendix
Appendix
Slide 37: Seralutinib In Vitro Profile
Seralutinib In Vitro Profile Seralutinib is a potent PDGFR, CSF1R and c-KIT inhibitor Cell Based IC50 (nM) Compound H1703 HLF PASMC CSF1R c-KIT PDGFRα PDGFβ>α PDGFRα=β Seralutinib 32 29 33 8 8 Imatinib 62 579 419 1032 301 Seralutinib is highly potent in PASMC and HLF proliferation assays HPASMC: hum
Slide 38: In the Phase 3 IMPRES Study of Imatinib in PAH, Safety Liabilities Outweighed Efficacy
In the Phase 3 IMPRES Study of Imatinib in PAH, Safety Liabilities Outweighed Clinically Meaningful Efficacy Clinical Efficacy Results Clinical Safety / Tolerability Phase 3 IMPRES Study Phase 3 IMPRES Study • Primary Endpoint: • Adverse Events: • 6-Minute Walk Distance (6MWD) • High rate of GI side
Slide 39: Seralutinib Employs Multiple Strategies to Mitigate Imatinib's Liabilities
Seralutinib Employs Multiple Strategies to Mitigate Imatinib’s Liabilities • Imatinib was developed & approved as an anti-cancer therapy Molecule Specifically • Seralutinib utilized Phase 3 IMPRES learnings and targets underlying biology of PAH, including PDGFR/, CSF1R and c-Kit Designed for PAH •
Slide 40: TORREY Phase 2 - Baseline Demographics (ITT Population)
TORREY Phase 2 - Baseline Demographics (ITT Population) Placebo Seralutinib Total Characteristic (N=42) (N=44) (N=86) Age (years) – mean (SD) 49.5 (11.81) 48.3 (12.70) 48.8 (12.22) Sex – n (%) Female 38 (90.5) 40 (90.9) 78 (90.7) Male 4 (9.5) 4 (9.1) 8 (9.3) Race – n (%) White 37 (88.1) 37 (84.1) 74
Slide 41: TORREY Phase 2 - Baseline Background PAH Medication Use
TORREY Phase 2 - Baseline Background PAH Medication Use(ITT Population) Placebo Seralutinib Total Characteristic (N=42) (N=44) (N=86) Number of background therapies – n (%) 1 2 (4.8) 1 (2.3) 3 (3.5) 2 16 (38.1) 18 (40.9) 34 (39.5) 3 24 (57.1) 25 (56.8) 49 (57.0) Prostacyclin/Prostacycin Receptor Ago
Slide 42: TORREY Phase 2 - Baseline Disease Characteristics
TORREY Phase 2 - Baseline Disease Characteristics (ITT Population) Placebo Seralutinib Total Characteristic (N=42) (N=44) (N=86) Age at PAH diagnosis (years) – mean (SD) 41.2 (11.65) 40.7 (15.84) 40.9 (13.87) Years since PAH diagnosis – mean (SD) 8.78 (7.218) 8.07 (7.074) 8.41 (7.111) PAH classifica
Slide 43: TORREY Phase 2 - Baseline Demographics and Disease Characteristics by Baseline WHO FC
TORREY Phase 2 - Baseline Demographics and Disease Characteristics by Baseline WHO FC (ITT Population) Baseline WHO FC Class II Baseline WHO FC Class III Placebo Seralutinib Total Placebo Seralutinib Total Characteristic (N=20) (N=30) (N=50) (N=22) (N=14) (N=36) Age (years) – mean (SD) 47.6 (11.69)