Slide 1: STARBORN-1 Clinical Trial Interim Update
STARBORN - 1 Clinical Trial Interim Update November 19, 2025
Slide 2: Forward Looking Statements
Forward Looking Statements 2 Statements contained in this presentation regarding matters that are not historical facts are "forward looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 . Protara may, in some cases, use terms such as “predicts,” “believes,” “
Slide 3: Agenda
Agenda Jesse Shefferman Co - founder, Director, Chief Executive Officer Jacqueline Zummo, PhD Co - founder, Senior Vice President, Chief Scientific Operations Officer Jesse G.A. Jones, MD University of Alabama – Department of Neurosurgery and Radiology, and STARBORN - 1 study investigator Introducti
Slide 4: Robust De-Risked Pipeline with Multiple Upcoming Opportunities
*Currently in pre - clinical studies to define dosing and, once protocol is confirmed, expect to initiate P2 trial cohort. **Granted Orphan Drug Designations by the U.S. FDA for the prevention and/or treatment of choline deficiency in patients on l on g - term PN and Fast Track Designation as a sour
Slide 5: LMs Represent a Significant Pediatric Rare Disease Opportunity with No Approved Therapies
© 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 5 LMs Represent a Significant Pediatric Rare Disease Opportunity with No Currently Approved Therapies Lymphatic Malformations (LMs) are rare, non - malignant, congenital malformations of lymphatic vessels resulting in th
Slide 6: Bringing the First FDA-approved Therapy to Market for Macrocystic and Mixed Cystic LMs
Lymphatic Malformations Incidence: 1,400 - 1,800 LM cases per year 1 © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 6 Bringing the First FDA - approved Therapy to Market for Macrocystic and Mixed Cystic LMs Provides a Significant Rare Disease Opportunity Prevalence S
Slide 7: Executive Summary: De-Risked Opportunity for a Significant Unmet Need
TARA - 002 HAS ROBUST SUPPORTING CLINICAL DATA IN LMS FROM PREDECESSOR COMPOUND, OK - 432 • OK - 432 has shown strong safety and efficacy results in 500+ U.S. pediatric LMs patients in University of Iowa - led study • Approved in Japan as standard of care for LMs for 30 years STARBORN - 1 DATA INDIC
Slide 8: LMs Overview & MOA
LMs Overview & TARA - 002 MOA © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 8
Slide 9: Investigational, Genetically Distinct Strain of Streptococcus Pyogenes, Inactivated
© 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 9 TARA - 002 is an Investigational, Genetically Distinct Strain of Streptococcus Pyogenes that is Inactivated While Retaining its Immune - Stimulating Properties First Immune Response Further Recruitment of Immune Cells
Slide 10: Immune Cascade Triggering Vessel Collapse and Fibrous Tissue Formation
© 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 10 Following the Immune Cascade Triggering Vessel Collapse, the Formation of Mature Fibrous Tissue Prevents Cyst Recurrence Improved Fluid Drainage Fibrotic Adhesion Healing and Tissue Remodeling Vessel Collapse and Long
Slide 11: Interim Data Update and OK-432 Data Review
TARA - 002 IN LMS Interim STARBORN - 1 Data Update and OK - 432 Data Review
Slide 12: Phase 2 Trial Design
6 years to < 18 years 2 years to < 6 years 6 months to < 2 years Phase 2a: Safety Lead - In Phase 2b: Expansion Age De - escalation Age De - escalation DMC Review DMC Review DMC Review Phase 2 STARBORN - 1 Trial © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 12 Enrol
Slide 13: Interim Results: Clinical Success Rate
© 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 13 Response was assessed via central imaging (MRI or CT) or via Investigator assessment (physical exam, visual inspection and ul tra sound). Clinical success is defined as complete (90 - 100% reduction) or substantial (6
Slide 14: Interim Results: Evaluable Patients Across Cyst Types
© 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 14 STARBORN - 1 Interim Results: Evaluable Patients Across Cyst Types • 2 patients have reached the 32 - weeks post - treatment assessment and remain disease free • One patient deemed a complete response was subsequently
Slide 15: Interim Results: Clinical Response Overview
STARBORN - 1 Interim Results: Clinical Response Overview Assessment of Response 8 Weeks after Last Injection Number of Doses of TARA - 002 Age LM Type Cohort / Patients* Ph2a: 6 - 18 years Complete Response 1 14 Ranula ( Dx’d macro)** 1 Complete Response 1 12 Mixed cystic 2 Withdrew 3 15 Mis - diagn
Slide 16: Favorable and Well-Tolerated Safety Profile
© 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 16 TARA - 002 Has a Favorable and Well - Tolerated Safety Profile Grade 4/5 Grade 3 Grade 2 Grade 1 Any Grade Number of Patients, N = 12 0 (0.0) 1 (8.3) 6 (50.0) 8 (66.7) 8 (66.7) TEAEs, n (%) 0 (0.0) 1 (8.3)
Slide 17: Demonstrated Meaningful Results in LMs Patients Treated in the Study
TARA - 002 Demonstrated Meaningful Results in LMs Patients Treated in the STARBORN - 1 Study BEFORE AFTER BEFORE AFTER 17 Medical photography from 2 patients pre - and post - treatment with TARA - 002 in STARBORN - 1 trial
Slide 18: OK-432 Clinical Success in Immediate Treatment Group
69% CLINICAL SUCCESS ǂ IN IMMEDIATE TREATMENT GROUP 6 MONTHS AFTER ENROLLMENT 84% * CLINICAL SUCCESS ǂ IN PATIENTS WITH MACROCYSTIC LESION TYPES 69% 7.5% Immediate Treatment Group (N=110) Delayed Treatment Group Pre-Treatment** (N=40) ITT: Observations 6 Months After Enrollment 62% 28% 0% 22% 32% Ma
Slide 19: Robust Clinical Results from OK-432, Predecessor
Robust Clinical Results from OK - 432 1 , Predecessor to TARA - 002 © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 19 Completed clinical study of OK - 432 in U.S. suggests effectiveness with strong support for safety profile BEFORE AFTER BEFORE AFTER BEFORE AFTER BEF
Slide 20: KOL Discussion
KOL Discussion Jesse G.A. Jones, M.D., University of Alabama – Department of Neurosurgery and Radiology, and STARBORN - 1 study investigator © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. |
Slide 21: Closing Remarks
Closing Remarks
Slide 22: Q&A
Q&A 22 Jesse Shefferman Co - founder, Director, Chief Executive Officer Jacqueline Zummo, PhD Co - founder, Senior Vice President, Chief Scientific Operations Officer Jesse G.A. Jones, MD University of Alabama – Department of Neurosurgery and Radiology, and STARBORN - 1 study investigator
Slide 23: Thank you!
Thank you! 6 Mrora RA THERAPEUTICS
Slide 24: Appendix
APPENDIX
Slide 25: Interim Results: Demographics and Baseline Characteristics
© 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 25 STARBORN - 1 Interim Results: Demographics and Baseline Characteristics Two patients who were initially diagnosed with macrocystic LMs at baseline had a change in diagnosis of their target cyst (po st - treatment): On