Ravulizumab in Thrombotic Microangiopathy After Hematopoietic Stem Cell Transplant

Phase 3

Active, not recruiting

• Conditions: Thrombotic Microangiopathy
• Interventions: Other: Placebo; Biological: Ravulizumab; Other: Best supportive care

• Registration Number: NCT04543591
• Lead Sponsor: Alexion Pharmaceuticals, Inc.

Brief Summary

This study will evaluate the efficacy, safety, pharmacokinetics, and pharmacodynamics of ravulizumab in adult and adolescent participants with hematopoietic stem cell transplant-associated thrombotic microangiopathy (HSCT-TMA). In Stage 1, an open-label, single-arm period, the dosing regimen will be confirmed. In Stage 2, participants will be randomized to receive either blinded ravulizumab plus best supportive care or matching placebo plus best supportive care. The treatment period is 26 weeks (open-label for Stage 1, and randomized, double-blind, and placebo-controlled for Stage 2) followed by a 26-week follow-up period.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2020-08-17
• Study First Submitted QC: 2020-09-02
• Study First Posted: 2020-09-10
• Study Start: 2020-12-10
• Primary Completion: 2025-04-30
• Status Verified: 2025-05
• Last Update Submitted: 2025-05-08
• Last Update Posted: 2025-05-11
• Study Completion: 2026-03-13

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 146

Inclusion Criteria

1. 12 years of age or older at time of consent/assent.
2. Received HSCT within the past 12 months.
3. Diagnosis of TMA that persists for at least 72 hours after initial management of any triggering agent/condition.
4. A TMA diagnosis based on meeting the laboratory-based criteria during the Screening Period and/or ≤14 days prior to the Screening Period.
5. Body weight ≥ 30 kilograms at Screening or ≤7 days prior to the start of the Screening Period (date of consent).
6. Female participants of childbearing potential and male participants with female partners of childbearing potential must use highly effective contraception.
7. Participants must be vaccinated against meningococcal infections if clinically feasible. Participants who cannot receive meningococcal vaccine should receive antibiotic prophylaxis. Participants <18 years of age must be re-vaccinated against Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae if clinically feasible.
8. Participants or their legally authorized representative must be capable of giving signed informed consent or assent.

Exclusion Criteria

1. Thrombotic thrombocytopenic purpura (TTP) evidenced by ADAMTS13 deficiency
2. Known Shiga toxin-related hemolytic uremic syndrome as demonstrated by positive test.
3. Positive direct Coombs test indicative of a clinically significant immune-mediated hemolysis not due to TMA.
4. Clinical diagnosis of disseminated intravascular coagulation (DIC).
5. Known bone marrow/graft failure for the current HSCT.
6. Diagnosis of veno-occlusive disease which is unresolved at the time of Screening.
7. Human immunodeficiency virus (HIV) infection.
8. Unresolved meningococcal disease.
9. Presence of sepsis requiring vasopressor support.
10. Pregnancy or breastfeeding.
11. Hypersensitivity to murine proteins or to one of the excipients of ravulizumab.
12. Any ongoing or history of medical or psychological conditions unrelated to HSCT-TMA that could increase the risk to the participant or confound the outcome of the study.
13. Respiratory failure requiring mechanical ventilation.
14. Acute and/or chronic heart failure with an ejection fraction ≤ 40%.
15. Previously or currently treated with a complement inhibitor.
16. Participation in an interventional treatment study of any therapy for TMA.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	In Stage 2, participants randomized to the placebo arm will receive matching placebo plus BSC.
Placebo	Best supportive care	In Stage 2, participants randomized to the placebo arm will receive matching placebo plus BSC.
Ravulizumab	Ravulizumab	In Stage 1, all participants will receive open-label ravulizumab plus Best Supportive Care (BSC). In Stage 2, participants will receive blinded ravulizumab plus Best Supportive Care (BSC).
Ravulizumab	Best supportive care	In Stage 1, all participants will receive open-label ravulizumab plus Best Supportive Care (BSC). In Stage 2, participants will receive blinded ravulizumab plus Best Supportive Care (BSC).

Primary Outcome Measures

Name	Time	Method
Event Free Survival	26 weeks (treatment period)	Event free survival during the 26 weeks treatment period defined as the time from randomization until the first of the two following events: death and clinical worsening.

Secondary Outcome Measures

Name	Time	Method
Duration of TMA Response	26 weeks (treatment period) and 52 weeks
Hematologic Response	26 weeks (treatment period)
TMA response and time to response for each individual component of TMA	26 weeks (treatment period)
Partial Response	26 weeks (treatment period)
Loss of TMA Response	26 weeks (treatment period)
Change from Baseline in eGFR	26 weeks (treatment period) and 52 weeks
Time to Hematologic Response	26 weeks (treatment period)
Time To TMA Response	26 weeks (treatment period)
Modified TMA Response	26 weeks (treatment period)
TMA Relapse	Follow-up Period
Overall Survival	Day 100, 26 weeks (treatment period), and 52 weeks
Non-relapse Mortality	Day 100, 26 weeks (treatment period), and 52 weeks
Hemoglobin Response	26 weeks (treatment period)
Changes from Baseline in Haptoglobin, Platelets, LDH, and Hemoglobin	26 weeks (treatment period) and 52 weeks
Change from baseline in TMA-associated organ dysfunction in renal system, cardiovascular system, pulmonary system, CNS, and GI system	26 weeks (treatment period) and 52 weeks
Platelet Response	26 weeks (treatment period)

Trial Locations

Locations (1)

Research Site; 🇬🇧 Nottingham, United Kingdom