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

Phase 3
Recruiting
Conditions
Thrombotic Microangiopathies
Atypical Hemolytic Uremic Syndrome
Interventions
Biological: OMS721
Registration Number
NCT03205995
Lead Sponsor
Omeros Corporation
Brief Summary

The purpose of this study is to evaluate the platelet count change from baseline and safety of OMS721 in adults and adolescents with atypical hemolytic uremic syndrome (aHUS). The study will also evaluate pharmacokinetics (PK), pharmacodynamics (PD), and anti-drug antibody response (ADA).

Detailed Description

This is a Phase 3, multicenter study of OMS721 in adults and adolescents with atypical hemolytic uremic syndrome (aHUS). The uncontrolled, open-label study will evaluate the effect of OMS721 in subjects with plasma therapy-resistant aHUS and plasma therapy-responsive aHUS. This study has four periods: Screening, Treatment Induction, Treatment Maintenance, and Follow-up. Approximate enrollment is 80 subjects. An interim analysis will be performed after 40 subjects have completed 26 weeks of treatment for potential registration.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
80
Inclusion Criteria
  • Competent to provide informed consent, or if a minor, have at least one parent or legal guardian to provide informed consent with written assent from the subject.
  • Are at least 12 years old at screening (Visit 1).
  • Have a clinically diagnosis of primary atypical hemolytic uremic syndrome (aHUS), with ADAMTS13 activity greater than 5% in plasma.
  • Plasma therapy-resistant aHUS patients must have a screening platelet count less than 150,000/uL, evidence of microangiopathic hemolysis, and serum creatinine greater than upper limit of normal.
  • Plasma therapy-responsive aHUS patients must have documented history of requiring plasma therapy to prevent aHUS exacerbation and received plasma therapy at least once every 2 weeks at an unchanged frequency for at least 8 weeks before first dose of OMS721.
Exclusion Criteria
  • Have STEC-HUS, a direct positive Coombs test, history of hematopoietic stem cell transplant, and/or HUS from an identified drug.
  • History of vitamin B12 deficiency-related HUS, systemic lupus erythematosus, and/or antiphospholipid syndrome.
  • Active cancer or history of cancer (except non-melanoma skin cancers) within 5 years of screening.
  • Have been on hemodialysis or peritoneal dialysis for greater than or equal to 12 weeks.
  • Have an active systemic bacterial or fungal infection requiring systemic antimicrobial therapy (prophylactic antimicrobial therapy administered as standard of care is allowed).
  • Baseline resting heart rate less than 45 beats per minute or greater than 115 beats per minute.
  • Baseline QTcF greater than 470 milliseconds.
  • Have malignant hypertension (diastolic blood pressure [BP] greater than 120 mm Hg with bilateral hemorrhages or "cotton-wool" exudates on funduscopic examination).
  • Have a poor prognosis with a life expectancy of less than three months in the opinion of the Investigator.
  • Are pregnant or lactating.
  • Have received treatment with an investigational drug or device within four weeks prior to screening.
  • Have abnormal liver function tests defined as ALT or AST > five times ULN.
  • Have HIV infection.
  • History of cirrhosis of the liver.
  • Have previously completed treatment in an OMS721study.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
OMS721OMS721Administration of OMS721
Primary Outcome Measures
NameTimeMethod
The effect of OMS721 as measured by platelet count change from baseline26 weeks

The effect of OMS721 will be evaluated in subjects with aHUS by changes in platelet count from baseline

Secondary Outcome Measures
NameTimeMethod
Incidence of antidrug antibodies (ADA)771 days post-dose

Incidences of ADA in subjects with aHUS, administered OMS721

Increase in eGFR26 weeks

Increase of greater than 15 ml/min/1.73 m2 in eGFR calculated by the MDRD Equation

TMA Remission26 weeks

Platelet count greater than or equal to 150,000/μL over at least 2 consecutive weeks, within the initial 26-week period

Change from baseline in serum creatinine26 weeks

Assessment of subject's change from baseline in serum creatinine

Safety as measured by incidences of Adverse Events, vital signs, ECG, and clinical laboratory testsPre-dose and up to 771 days post-dose

Assessment of safety of OMS721 in subjects with aHUS by incidence of Adverse Events, clinically significant vital sign abnormalities, ECG abnormalities, and clinical laboratory test abnormalities

Hematological Normalization26 weeks

Normalization of platelet count and normalization of serum LDH by 2 consecutive measurements over at least 4 consecutive weeks, within the initial 26-week period

Change from baseline in serum LDH26 weeks

Assessment of subject's change from baseline in serum LDH

TMA Response26 weeks

Complete TMA response defined as normalization of platelet count, normalization of serum 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

TMA event-free status26 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

Change from baseline in haptoglobin26 weeks

Assessment of subject's change from baseline in haptoglobin

Pharmacokinetics (PK): Trough plasma concentration, lower limit of quantification (LLOQ)Days 1-4; Treatment Maintenance (103 weeks): 17 visits; Rescue Therapy (if occurs): RT Days 1-4; Follow-Up at Day 771
Pharmacokinetics (PK): Area under time-concentration curve (AUC)Days 1-4; Treatment Maintenance (103 weeks): 17 visits; Rescue Therapy (if occurs): RT Days 1-4; Follow-Up at Day 771
Pharmacodynamics (PD): Inhibition of C4 activityDays 1-4; Treatment Maintenance (103 weeks): 17 visits; Rescue Therapy (if occurs): RT Days 1-4; Follow-Up at Day 771
Pharmacokinetics (PK): Maximum plasma concentrations (Cmax)Days 1-4; Treatment Maintenance (103 weeks): 17 visits; Rescue Therapy (if occurs): RT Days 1-4; Follow-Up at Day 771
Pharmacodynamics (PD): Inhibition of C3 activityDays 1-4; Treatment Maintenance (103 weeks): 17 visits; Rescue Therapy (if occurs): RT Days 1-4; Follow-Up at Day 771

Trial Locations

Locations (1)

Omeros Investigational Site

🇺🇸

Chicago, Illinois, United States

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