Tibulizumab Systemic Sclerosis Understanding and Response Evaluation (TibuSURE)

Phase 2

Recruiting

• Conditions: Systemic Sclerosis (SSc); Scleroderma
• Interventions: Biological: Tibulizumab; Other: Placebo

• Registration Number: NCT06843239
• Lead Sponsor: Zura Bio Inc

Brief Summary

The study is a Phase 2, multi-center, randomized, double-blind, placebo-controlled study to evaluate the effects of tibulizumab over 24 weeks (Period 1) in adult participants with systemic sclerosis, followed by an open-label extension period where all active participants will receive tibulizumab and will be evaluated for an additional 28 weeks (Period 2)

Detailed Description

Not available

Study Timeline

• Study Start: 2025-02-06
• Study First Submitted: 2025-02-07
• Study First Submitted QC: 2025-02-20
• Study First Posted: 2025-02-24
• Status Verified: 2025-08
• Last Update Submitted: 2025-08-01
• Last Update Posted: 2025-08-06
• Primary Completion: 2026-12
• Study Completion: 2027-05-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 80

Inclusion Criteria

• Male or female, 18 to 75 years of age
• Body mass index between 18.0 and 38.0 kg/m²
• Fulfills classification criteria for SSc according to ACR/EULAR 2013 criteria
• Has diffuse cutaneous SSc, defined as mRSS >0 over at least one skin area proximal to the elbows and/or knees, in addition to acral fibrosis
• Has had SSc (defined as the first non-Raynaud's phenomenon (RP) symptom or sign attributed to SSc) for ≤7 years
• mRSS ≥15 and ≤45 at screening. Additional requirements for participants ≥2 years to ≤7 years from SSc onset and RNA Polymerase III antibody positive
• FVC >50% predicted
• Diffusing capacity of the lungs for carbon monoxide (DLCO) ≥40% predicted (corrected for hemoglobin)

Exclusion Criteria

• Has any of the following complications:

  • Left ventricular failure
  • Pulmonary arterial hypertension
  • Renal crisis within previous 6 months
  • Gastrointestinal dysmotility within previous 3 months
  • Digital ischemia with gangrene, amputation, or unscheduled hospitalization within previous 3 months

• Current rheumatic disease other than SSc that could interfere with assessment of SSc

• Lung disease requiring continuous oxygen therapy

• Evidence or suspicion of active or latent tuberculosis

• Active Crohn's Disease or ulcerative colitis

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Tibulizumab	Tibulizumab	Subcutaneous injection
Placebo	Tibulizumab	Subcutaneous injection
Placebo	Placebo	Subcutaneous injection

Primary Outcome Measures

Name	Time	Method
[Period 1] Change from baseline in modified Rodnan Skin Score (mRSS) at 24 weeks	Week 24	The mRSS assesses skin thickness at 17 different cutaneous sites across the body using a scale from 0 (normal skin) to 3 (severe thickening), with a total score ranging from 0 (no thickening) to 51 (severe thickening in all 17 areas); Estimated Primary Completion Date above (Dec 2026) corresponds to the randomized, double blind, placebo controlled portion of study
[Period 2] Safety and tolerability of tibulizumab	Week 52	Assessed by the incidence of all treatment-emergent adverse events (TEAEs), as well as changes from baseline in vital signs, electrocardiogram (ECG) parameters, and laboratory results; Estimated Study Completion Date above (May 2027) corresponds to the open-label extension portion of study

Secondary Outcome Measures

Name	Time	Method
[Period 1] Change from baseline in quantitative interstitial lung disease (QILD) obtained with high-resolution quantitative tomography (HRCT) in the whole lung in participants with SSc-interstitial lung disease (ILD)	Week 24	HRCT measures the extent of interstitial lung disease by quantifying the amount of lung fibrosis, ground-glass opacity, and honeycomb lung, which are used to calculate the QILD score (scores can range from 0 to 100%, with higher scores indicating greater disease extent)
[Period 1] Change from baseline in forced vital capacity (FVC)	Week 24	FVC is the amount of air that can be forcibly exhaled after the deepest possible breath
[Period 1] Change from baseline in Health Assessment Questionnaire Disability Index (HAQ-DI)	Week 24	HAQ-DI evaluates patients' self-assessed degree of disability across eight categories, with scores ranging from 0 to 3, where 3 indicates the worst degree of disability
[Period 1] Safety and tolerability of tibulizumab	Week 24	Assessed by the incidence of all TEAEs, as well as changes from baseline in vital signs, ECG parameters, and laboratory results
[Period 2] Change from baseline in mRSS	Week 52	The mRSS assesses skin thickness at 17 different cutaneous sites across the body using a scale from 0 (normal skin) to 3 (severe thickening), with a total score ranging from 0 (no thickening) to 51 (severe thickening in all 17 areas)
[Period 2] Change from baseline in QILD obtained with HRCT in the whole lung in participants with SSc-ILD	Week 52	HRCT measures the extent of interstitial lung disease by quantifying the amount of lung fibrosis, ground-glass opacity, and honeycomb lung, which are used to calculate the QILD score (scores can range from 0 to 100%, with higher scores indicating greater disease extent)

Trial Locations

Locations (6)

IRIS Research and Development LLC; 🇺🇸 Plantation, Florida, United States

University of Iowa; 🇺🇸 Iowa City, Iowa, United States

University of Michigan Hospital; 🇺🇸 Ann Arbor, Michigan, United States

Rheumatology Associates; 🇺🇸 Arlington, Texas, United States

Institute of Rheumatology - PPDS; 🇷🇸 Belgrade, Serbia

Royal Free Hospital; 🇬🇧 London, United Kingdom