Trial · NCT04557735

Study of Ravulizumab in Pediatric Participants With HSCT-TMA

NCT04557735, Phase 3, Completed, Alexion Pharmaceuticals, Inc.; results first posted 2026-01-12

3 sourcestrials-2026-11-12-0.5.0

Cite this record

ConductScience Library. Study of Ravulizumab in Pediatric Participants With HSCT-TMA. Trials, record NCT04557735. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT04557735

On this page

Trial

As registered on ClinicalTrials.gov, in the graph's capture of the registry.

Title: Study of Ravulizumab in Pediatric Participants With HSCT-TMA
NCT number: NCT04557735
Status: Completed
Phases: Phase 3
Enrollment: 41 participants, actual
Lead sponsor: Alexion Pharmaceuticals, Inc.
Conditions: Thrombotic Microangiopathy
Interventions: Ravulizumab, Best Supportive Care
First posted: 2020-09-22
Last updated: 2026-01-12
Other registries' IDs: eudract:2020-000761-16
Results first posted: 2026-01-12

Source ClinicalTrials.gov

Registered outcomes12

Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.

List	Outcome	Time frame	Description
Primary	Participants With Thrombotic Microangiopathy (TMA) Response	Up to Week 26	The criteria for TMA response were: 1. Normalization of platelet count (defined as platelet count ≥ 50000 mm\^3 or \>=50% increase in platelet count) without transfusion support during the prior 7 days. 2. Normalization of lactate dehydrogenase (LDH, defined as LDH ≤ upper limit of normal \[ULN\]) and absence of schistocytes. 3. At least 50% reduction in protein/creatinine ratio from baseline. Participants must meet each TMA criterion at 2 separate assessments obtained at least 24 hours apart, with no criteria failures or more than 1 missed scheduled visit in between. Additionally, all intervals in which the criteria were met must overlap for at least 1 day.
Secondary	Time to TMA Response During the 26-Week Treatment Period	Day 1 through Week 26	Time to TMA response was defined as the time from first infusion to the first time point at which all criteria for TMA response was met. Participants were assigned as responders at the time of their TMA response and were censored at the earlier of last assessment with all 3 TMA response components available (including measurements collected after treatment discontinuation), or death if they did not respond by then. TMA response required the following: 1. Normalization of platelet count (defined as platelet count ≥ 50000 mm\^3 or \>=50% increase in platelet count) without transfusion support during the prior 7 days. 2. Normalization of LDH (defined as LDH ≤ULN) and absence of schistocytes. 3. At least 50% reduction in protein/creatinine ratio from baseline.
Secondary	Participants With Hematologic Response	Up to Week 26	Hematologic response required the following: (1) Normalization of platelet count (defined as platelet count ≥ 50000 mm\^3 or \>=50% increase in platelet count) without transfusion support during the prior 7 days and (2) Normalization of LDH (defined as LDH ≤ULN) and absence of schistocytes.
Secondary	Time to Hematologic Response During the 26-Week Treatment Period	Day 1 through Week 26	Time to Hematologic response was defined as the time from first infusion to the first time point at which all criteria for hematologic response was met. Participants were assigned as responders at the time of their response and were censored at their discontinuation time or at the end of available follow-up if they did not respond by then. Hematologic response required the following: (1) Normalization of platelet count (defined as platelet count ≥ 50000 mm\^3 or \>=50% increase in platelet count) without transfusion support during the prior 7 days and (2) Normalization of LDH (defined as LDH ≤ULN) and absence of schistocytes.
Secondary	Participants With Hemoglobin Response	Up to Week 26	Hemoglobin response was defined as the ability to maintain hemoglobin ≥ 10 g/dL without RBC transfusion support. The criterion must have been met at 2 separate assessments obtained at least 24 hours apart, and any measurement in between, and without RBC transfusion support during the prior 7 days.
Secondary	Participants With Platelet Response	Up to Week 26	Normalization of platelet count was defined as baseline platelet count ≤ 50000 mm\^3 or \> 50000 mm\^3, absolute platelet count \> 50000 mm\^3 or \>=50% increase in platelet count without transfusion support during the prior 7 days.
Secondary	Participants With Partial TMA Response	Up to Week 26	Partial response was defined as a participant meeting at least 1, but not all, criteria for TMA response. TMA response required the following: 1. Normalization of platelet count (defined as platelet count ≥ 50000 mm\^3 or \>=50% increase in platelet count) without transfusion support during the prior 7 days. 2. Normalization of LDH, (defined as LDH ≤ULN) and absence of schistocytes. 3. At least 50% reduction in protein/creatinine ratio from baseline.
Secondary	Participants With Loss of TMA Response	Up to Week 26	Loss of response occurred when a participant who had previously achieved a TMA response failed to meet criteria for one or more components of TMA response at a subsequent visit in treatment period. At least one parameter must fail to meet response criteria at 2 separate assessments obtained at least 24 hours apart, and any measurement in between. TMA response required the following: 1. Normalization of platelet count (defined as platelet count ≥ 50000 mm\^3 or \>=50% increase in platelet count) without transfusion support during the prior 7 days. 2. Normalization of LDH (defined as LDH ≤ULN) and absence of schistocytes. 3. At least 50% reduction in protein/creatinine ratio from baseline.
Secondary	Duration of TMA Response Through Week 52	Day 1 through Week 52	This analysis includes data for each participant after TMA response through final follow-up. Participants with TMA response who do not experience these events are censored at their end of study date. TMA response required following: 1. Normalization of platelet count (defined as platelet count ≥ 50000 mm\^3 or \>=50% increase in platelet count) without transfusion support during the prior 7 days. 2. Normalization of LDH (defined as LDH ≤ULN) and absence of schistocytes. 3. At least 50% reduction in protein/creatinine ratio from baseline. The estimate is calculated based on Kaplan-Meier method.
Secondary	Participants With TMA Relapse	Up to Week 52	For participants that meet criteria for TMA response during 26-week Treatment Period, TMA relapse is defined as evidence of worsening hematologic and renal dysfunction due to TMA during post-treatment Follow-up Period that requires treatment intervention, as determined by Investigator. TMA response required the following: 1. Normalization of platelet count (defined as platelet count ≥ 50000 mm\^3 or \>=50% increase in platelet count) without transfusion support during the prior 7 days. 2. Normalization of LDH (defined as LDH ≤ULN) and absence of schistocytes. 3. At least 50% reduction in protein/creatinine ratio from baseline.

1 to 10 of 12Source ClinicalTrials.gov

See all 12 registered outcomes

Outcomes12

Each outcome the trial posted results for, in ClinicalTrials.gov's words.

Type	Outcome	Time frame	Population	Units	Measured as
PRIMARY	Participants With Thrombotic Microangiopathy (TMA) Response	Up to Week 26	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of shiga toxin-related hemolytic uremic syndrome (ST-HUS) and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) laboratory results and are subsequently found to be ineligible after enrollment.	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Time to TMA Response During the 26-Week Treatment Period	Day 1 through Week 26	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of ST-HUS and ADAMTS13 laboratory results and are subsequently found to be ineligible after enrollment.	days	MEDIAN
SECONDARY	Participants With Hematologic Response	Up to Week 26	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of ST-HUS and ADAMTS13 laboratory results and are subsequently found to be ineligible after enrollment.	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Time to Hematologic Response During the 26-Week Treatment Period	Day 1 through Week 26	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of ST-HUS and ADAMTS13 laboratory results and are subsequently found to be ineligible after enrollment. Here, overall number of participants analyzed signifies those participants who were evaluable for this outcome measure.	days	MEDIAN
SECONDARY	Participants With Hemoglobin Response	Up to Week 26	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of ST-HUS and ADAMTS13 laboratory results and are subsequently found to be ineligible after enrollment.	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Participants With Platelet Response	Up to Week 26	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of ST-HUS and ADAMTS13 laboratory results and are subsequently found to be ineligible after enrollment.	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Participants With Partial TMA Response	Up to Week 26	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of ST-HUS and ADAMTS13 laboratory results and are subsequently found to be ineligible after enrollment.	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Participants With Loss of TMA Response	Up to Week 26	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of ST-HUS and ADAMTS13 laboratory results and are subsequently found to be ineligible after enrollment. Here, overall number of participants analyzed signifies those participants who were evaluable for this outcome measure.	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Duration of TMA Response Through Week 52	Day 1 through Week 52	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of ST-HUS and ADAMTS13 laboratory results and are subsequently found to be ineligible after enrollment. Here, overall number of participants analyzed signifies those participants who were evaluable for this outcome measure.	days	MEDIAN
SECONDARY	Participants With TMA Relapse	Up to Week 52	Full analysis set included all participants who signed the informed consent and received at least 1 dose of ravulizumab, excluding participants who enrolled prior to availability of ST-HUS and ADAMTS13 laboratory results and are subsequently found to be ineligible after enrollment. Here, overall number of participants analyzed signifies those participants who were evaluable for this outcome measure.	Participants	COUNT_OF_PARTICIPANTS

1 to 10 of 12Source ClinicalTrials.gov

See all 12 outcomes

Results by group12

Each measurement the trial posted, group by group, in the words and numbers it posted.

Outcome	Group	Value	Spread	Units
Participants With Thrombotic Microangiopathy (TMA) Response	Ravulizumab	7		Participants
Time to TMA Response During the 26-Week Treatment Period	Ravulizumab	NA	95% Confidence Interval 154.0 to NA	days
Participants With Hematologic Response	Ravulizumab	10		Participants
Time to Hematologic Response During the 26-Week Treatment Period	Ravulizumab	NA	95% Confidence Interval 154.0 to NA	days
Participants With Hemoglobin Response	Ravulizumab	17		Participants
Participants With Platelet Response	Ravulizumab	24		Participants
Participants With Partial TMA Response	Ravulizumab	22		Participants
Participants With Loss of TMA Response	Ravulizumab	2		Participants
Duration of TMA Response Through Week 52	Ravulizumab	NA	95% Confidence Interval 22.0 to NA	days
Participants With TMA Relapse	Ravulizumab	0		Participants

1 to 10 of 12Source ClinicalTrials.gov

See all 12 results by group

Participant flow7

How many started, completed or left each group, period by period.

Period	Milestone	Group	Participants
Treatment Period (26 Weeks)	STARTED	Ravulizumab	41
Treatment Period (26 Weeks)	Received at Least 1 Dose of Study Drug	Ravulizumab	41
Treatment Period (26 Weeks)	COMPLETED	Ravulizumab	29
Treatment Period (26 Weeks)	NOT COMPLETED	Ravulizumab	12
Follow-Up Period (26 Weeks)	STARTED	Ravulizumab	29
Follow-Up Period (26 Weeks)	COMPLETED	Ravulizumab	24
Follow-Up Period (26 Weeks)	NOT COMPLETED	Ravulizumab	5

Source ClinicalTrials.gov

Adverse events278

Each adverse event the trial posted, group by group: the participants affected out of those at risk.

Type	Event	Organ system	Group	Affected	At risk	Events
other	Anaemia	Blood and lymphatic system disorders	Treatment Period: Ravulizumab	6	41	77
other	Anaemia	Blood and lymphatic system disorders	Follow-up Period: Ravulizumab	0	29	0
other	Neutropenia	Blood and lymphatic system disorders	Treatment Period: Ravulizumab	5	41	13
other	Neutropenia	Blood and lymphatic system disorders	Follow-up Period: Ravulizumab	1	29	1
other	Pericardial effusion	Cardiac disorders	Treatment Period: Ravulizumab	6	41	9
other	Pericardial effusion	Cardiac disorders	Follow-up Period: Ravulizumab	0	29	0
other	Bradycardia	Cardiac disorders	Treatment Period: Ravulizumab	3	41	3
other	Bradycardia	Cardiac disorders	Follow-up Period: Ravulizumab	0	29	0
other	Tachycardia	Cardiac disorders	Treatment Period: Ravulizumab	1	41	1
other	Tachycardia	Cardiac disorders	Follow-up Period: Ravulizumab	3	29	3

1 to 10 of 278Source ClinicalTrials.gov

See all 278 adverse events

Adverse event totals6

The totals the trial posted for each group.

Total	Group	Affected	At risk
Total, all-cause mortality	Treatment Period: Ravulizumab	6	41
Total, all-cause mortality	Follow-up Period: Ravulizumab	4	29
Total, other adverse events	Treatment Period: Ravulizumab	41	41
Total, other adverse events	Follow-up Period: Ravulizumab	23	29
Total, serious adverse events	Treatment Period: Ravulizumab	30	41
Total, serious adverse events	Follow-up Period: Ravulizumab	15	29

Source ClinicalTrials.gov

Papers0

The papers the trial lists on ClinicalTrials.gov.

None in this release.

Grants0

The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.

None in this release.

Trial comparisons2

Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.

Comparison	Source
Treatment Period: Ravulizumab vs Follow-up Period: Ravulizumab: deaths from any cause	Trial comparisons
Treatment Period: Ravulizumab vs Follow-up Period: Ravulizumab: serious adverse events	Trial comparisons

Tests0

The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.

None in this release.

Data dates

The day each source was copied for this release.

ClinicalTrials.gov: 2026-11-12; ClinicalTrials.gov
Results, from AACT: 2026-03-23; AACT
NIH grant links: 2026-11-13; NIH RePORTER

Sources 3

ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
ClinicalTrials.govNo license stated
NIH RePORTER's clinical studies and project filesPublic domain

Each source's terms

ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
ClinicalTrials.govnone stated
NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)

ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

For software

Read this trial from software.

The record and each of its lists are JSON, twenty rows a page. No key.

GET https://conductscience.org/api/trials/v1/NCT04557735

GET https://conductscience.org/api/trials/v1/NCT04557735/events?page=2

API reference For AI assistants