Trial · NCT03205995

Safety and Efficacy Study of OMS721 in Patients With Atypical Hemolytic Uremic Syndrome

NCT03205995, Phase 3, Terminated, Omeros Corporation; results first posted 2025-12-10

3 sourcestrials-2026-11-12-0.5.0

Cite this record

ConductScience Library. Safety and Efficacy Study of OMS721 in Patients With Atypical Hemolytic Uremic Syndrome. Trials, record NCT03205995. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT03205995

On this page

Trial

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

Title: Safety and Efficacy Study of OMS721 in Patients With Atypical Hemolytic Uremic Syndrome
NCT number: NCT03205995
Status: Terminated
Phases: Phase 3
Enrollment: 6 participants, actual
Lead sponsor: Omeros Corporation
Conditions: Thrombotic Microangiopathies, Atypical Hemolytic Uremic Syndrome
Interventions: OMS721 (narsoplimab)
First posted: 2017-07-02
Last updated: 2025-12-10
Results first posted: 2025-12-10

Source ClinicalTrials.gov

Registered outcomes16

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

List	Outcome	Time frame	Description
Primary	Platelet Count (10^9 Platelets/L) Change From Baseline at Week 26	Week 26	The primary outcome to be measured is platelet count change from baseline.
Secondary	Safety as Measured by Incidences of Adverse Events, Vital Signs, ECG, and Clinical Laboratory Tests	Pre-dose and up to 771 days post-dose	Assessment of safety of OMS721 (narsoplimab) in participants with aHUS by incidence of Adverse Events, clinically significant vital sign abnormalities, ECG abnormalities, and clinical laboratory test abnormalities
Secondary	Thrombotic Microangiopathies (TMA) Response	26 weeks	Complete TMA response defined as normalization of platelet count, normalization of serum lactate dehydrogenase (LDH), and \> 25% decrease in serum creatinine by at least 2 consecutive measures over at least 4 consecutive weeks, within the initial 26-week period
Secondary	TMA Event-free Status	26 weeks	No decrease in platelet count of \> 25% from baseline, no plasma exchange or plasma infusion, and no initiation of new dialysis over at least 12 consecutive weeks, within the initial 26-week period
Secondary	Increase in Estimated Glomerular Filtration Rate (eGFR)	26 weeks	Increase of greater than 15 ml/min/1.73 m2 in eGFR calculated by the modification of diet in renal disease (MDRD) Equation
Secondary	Hematological Normalization	26 weeks	Normalization of platelet count and normalization of serum LDH by 2 consecutive measurements over at least 4 weeks, within the initial 26-week period
Secondary	TMA Remission	26 weeks	Platelet count greater than or equal to 150,000/μL on at least 2 consecutive measures over at least 2 consecutive weeks, within the initial 26-week period
Secondary	Incidence of Antidrug Antibodies (ADA)	771 days post-dose	Incidences of ADA in participants with aHUS, administered OMS721 (narsoplimab)
Secondary	Change From Baseline in Serum Creatinine (mg/dL)	26 weeks	Assessment of subject's change from baseline in serum creatinine.
Secondary	Change From Baseline in Serum LDH (U/L)	26 weeks	Assessment of subject's change from baseline in serum LDH

1 to 10 of 16Source ClinicalTrials.gov

See all 16 registered outcomes

Outcomes16

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

Type	Outcome	Time frame	Population	Units	Measured as
PRIMARY	Platelet Count (10^9 Platelets/L) Change From Baseline at Week 26	Week 26	Any patent who received drug	10^9 platelets/L	MEDIAN
SECONDARY	Safety as Measured by Incidences of Adverse Events, Vital Signs, ECG, and Clinical Laboratory Tests	Pre-dose and up to 771 days post-dose	The safety population includes all participants who received any amount of study drug.	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Thrombotic Microangiopathies (TMA) Response	26 weeks	Any patient who received drug	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	TMA Event-free Status	26 weeks	Any patient who received drug	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Increase in Estimated Glomerular Filtration Rate (eGFR)	26 weeks	Any patient who received drug	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Hematological Normalization	26 weeks	Any patient who received drug	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	TMA Remission	26 weeks	Any patient who received drug	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Incidence of Antidrug Antibodies (ADA)	771 days post-dose	Any patient who received drug	Participants	COUNT_OF_PARTICIPANTS
SECONDARY	Change From Baseline in Serum Creatinine (mg/dL)	26 weeks	Any patient who received drug	mg/dL	MEDIAN
SECONDARY	Change From Baseline in Serum LDH (U/L)	26 weeks	Any patient who received drug.	U/L	MEDIAN

1 to 10 of 16Source ClinicalTrials.gov

See all 16 outcomes

Results by group15

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

Outcome	Group	Value	Spread	Units
Platelet Count (10^9 Platelets/L) Change From Baseline at Week 26	OMS721 (Narsoplimab)	42	Full Range -21 to 115.5	10^9 platelets/L
Safety as Measured by Incidences of Adverse Events, Vital Signs, ECG, and Clinical Laboratory Tests	OMS721 (Narsoplimab)	6		Participants
Thrombotic Microangiopathies (TMA) Response	OMS721 (Narsoplimab)	0		Participants
TMA Event-free Status	OMS721 (Narsoplimab)	2		Participants
Increase in Estimated Glomerular Filtration Rate (eGFR)	OMS721 (Narsoplimab)	0		Participants
Hematological Normalization	OMS721 (Narsoplimab)	1		Participants
TMA Remission	OMS721 (Narsoplimab)	2		Participants
Incidence of Antidrug Antibodies (ADA)	OMS721 (Narsoplimab)	1		Participants
Change From Baseline in Serum Creatinine (mg/dL)	OMS721 (Narsoplimab)	1.53	Full Range -0.98 to 3.16	mg/dL
Change From Baseline in Serum LDH (U/L)	OMS721 (Narsoplimab)	-12	Full Range -112 to 389	U/L

1 to 10 of 15Source ClinicalTrials.gov

See all 15 results by group

Participant flow3

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

Period	Milestone	Group	Participants
Overall Study	STARTED	OMS721 (Narsoplimab)	6
Overall Study	COMPLETED	OMS721 (Narsoplimab)	0
Overall Study	NOT COMPLETED	OMS721 (Narsoplimab)	6

Source ClinicalTrials.gov

Adverse events78

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	BRADYCARDIA	Cardiac disorders	OMS721 (Narsoplimab)	1	6	2
other	HAEMOLYSIS	Blood and lymphatic system disorders	OMS721 (Narsoplimab)	2	6	4
other	IRON DEFICIENCY ANAEMIA	Blood and lymphatic system disorders	OMS721 (Narsoplimab)	1	6	1
other	CARDIAC FAILURE	Cardiac disorders	OMS721 (Narsoplimab)	1	6	5
other	HYPERTROPHIC CARDIOMYOPATHY	Congenital, familial and genetic disorders	OMS721 (Narsoplimab)	1	6	1
other	ADRENAL INSUFFICIENCY	Endocrine disorders	OMS721 (Narsoplimab)	1	6	1
other	HYPERTHYROIDISM	Endocrine disorders	OMS721 (Narsoplimab)	1	6	1
other	ASCITES	Gastrointestinal disorders	OMS721 (Narsoplimab)	1	6	1
other	DIARRHOEA	Gastrointestinal disorders	OMS721 (Narsoplimab)	1	6	1
other	ENTEROCOLITIS	Gastrointestinal disorders	OMS721 (Narsoplimab)	1	6	1

1 to 10 of 78Source ClinicalTrials.gov

See all 78 adverse events

Adverse event totals3

The totals the trial posted for each group.

Total	Group	Affected	At risk
Total, all-cause mortality	OMS721 (Narsoplimab)	1	6
Total, other adverse events	OMS721 (Narsoplimab)	6	6
Total, serious adverse events	OMS721 (Narsoplimab)	5	6

Source ClinicalTrials.gov

Papers1

The papers the trial lists on ClinicalTrials.gov.

PMID	Listed as
33783815	DERIVED

Source PubMed

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 comparisons0

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

None in this release.

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/NCT03205995

GET https://conductscience.org/api/trials/v1/NCT03205995/events?page=2

API reference For AI assistants