ClinicalTrials.gov record NCT07308574

Post-Marketing Clinical Study of Ravulizumab in Participants With Clinical aHUS

Record copied from ClinicalTrials.gov: Oct 10, 2026AI summaries generated: Aug 22, 2026

Multicenter, Open-label, Single-arm, Post-Marketing Clinical Study to Evaluate the Efficacy and Safety of Ravulizumab in Participants Clinically Diagnosed as Atypical Hemolytic Uremic Syndrome

About this page. This page shows the study's official ClinicalTrials.gov record ↗, with added help to make it easier to understand. We explain medical terms, highlight key details in plain language, and suggest questions you may want to ask the study team.

The record is periodically copied from ClinicalTrials.gov and may lag behind changes. AI summaries are checked by software, not a clinician.Read moreShow less

The official record is written by the study sponsor and published on ClinicalTrials.gov. It may not always reflect the latest changes. Before making any decisions, please confirm important information with the study team and your own healthcare team.

Where you see "AI summary", AI was used to create a plain-language explanation and software checked it against the source. It has not been reviewed by a clinician, so it may contain mistakes or leave out important details.

StatusRecruitingThe study is currently enrolling participants. Only the study team can say whether a particular person can join.

Study typeInterventionalA study in which researchers assign participants to one or more interventions, such as a drug, procedure, device, behavioural programme or other approach, to measure their effects.

PhasePhase 4A study of a treatment that is already approved, to learn more about its long-term effects, safety or use in everyday practice.

Age18 years old and older

SexAll

LocationJapan

AI summaryWhat this study is about, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

This open-label, single-group Phase 4 study gives ravulizumab by IV to adults clinically diagnosed with atypical HUS (aHUS) and follows them for 26 weeks. Key eligibility gates include age 18+, starting ravulizumab within 14 days of the latest thrombotic microangiopathy (TMA) episode, no prior treatment with complement inhibitors, and exclusion of people with certain complement gene variants or positive anti–factor H antibodies. The main measurement is platelet count response; kidney function and other TMA-related outcomes are also measured.

What it is studying. The study is testing how ravulizumab affects platelet counts and kidney-related measures in people clinically diagnosed with aHUS over a 26-week treatment period.

What the researchers hope to learn. To evaluate the efficacy and safety of ravulizumab in clinically diagnosed aHUS; primary goal is to measure platelet count response during 26 weeks of treatment. Secondary goals include measuring changes in renal function, rates of complete or partial TMA response, dialysis withdrawal among those on dialysis at baseline, and related laboratory changes.

What this study is about

The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.

The primary objective of this study is to assess the platelet count response to ravulizumab in participants clinically diagnosed as atypical hemolytic uremic syndrome (aHUS).

Interventions being studied

Being studied in this trial does not mean the treatment or procedure is approved or available for this condition.

Drug: Ravulizumab

Eligibility

The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.

Inclusion criteria

Body weight ≥20 kilograms (kg)
Participants clinically diagnosed as aHUS who have any of diseases/conditions listed below (including participants in whom Thrombotic microangiopathy (TMA) has not been improved even after treatment for the pathogenesis of diagnosed secondary TMA and therefore, diagnosis of aHUS was made).
Infection (except for pneumococcal infection and Siga toxin-producing Escherichia coli infection)
During pregnancy or postpartum
Post-renal transplantation
Hypertensive crisis/malignant hypertension
Systemic lupus erythematosus and related diseases (e.g. dermatomyositis, mixed connective tissue disease, etc.)
Participants with the following three signs:
Thrombocytopenia: Platelet count <150,000/microliter (μL)
Microangiopathic haemolytic anaemia: Hb < 10 grams per deciliter (g/dL) (*)
Acute kidney injury: one of the following is fulfilled; 1. ΔsCr ≥ 0.3 milligrams per deciliter (mg/dL) (within 48 hours), 2. 1.5-fold increase from baseline sCr (within 7 days), 3. urinary output ≤ 0.5 mL/kg/hour for ≥ 6 hours.
No prior treatment with complement inhibitors.
The investigator plans to provide the participant with 26-week treatment with ravulizumab in accordance with the treatment policy in clinical practice.
Ravulizumab treatment is planned to be initiated within 14 days after onset of the latest TMA episode.
Participants consenting to meningococcal vaccine administration and appropriate antibiotic prophylaxis (if required).

Exclusion criteria

Participants with TTP, STEC-HUS, secondary TMA that is obviously unrelated to complement abnormality.
Participants with TMA caused by malignant tumors, abnormal Cobalamin C metabolism, Streptococcus pneumoniae, drugs, autoimmune diseases other than systemic lupus erythematosus and related diseases (e.g. scleroderma etc.), or hematopoietic stem cell transplantation
Participants with pathological complement gene variants (CFH, CFI , CD46 (MCP), C3, CFB, THBD, DGKE) associated with the development of aHUS at enrolment
Participants with positive anti-factor H antibodies
More than 14 day from onset of TMA to the planned start of ravulizumab treatment
Chronic kidney disease or irreversible renal impairment that requires chronic dialysis
Presence of unresolved meningococcal disease
Judgement by the investigator that the participant is not eligible for the study

Study description and what participation involves

The registry record has no detailed description beyond the summary above.

AI summaryWhat participation may involve, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

Participants receive ravulizumab by intravenous (IV) infusion: a weight‑based loading dose, a second dose two weeks later, then weight‑based maintenance infusions every 8 weeks for a planned 26‑week treatment. They will attend scheduled clinic visits with blood tests to monitor platelet counts, hemoglobin, kidney function and other safety measures (assessments occur at baseline, Day 4 and on Weeks 1, 2, 10, 18 and 26). Participants must accept meningococcal vaccination and any required antibiotic prophylaxis before treatment. Dialysis status will be recorded; the study tracks whether people on dialysis at baseline are able to stop dialysis by Week 26.

How the study is structured. Interventional, open-label, single-group Phase 4 trial. Participants receive weight-based IV ravulizumab (loading dose, a second dose after 2 weeks, then maintenance every 8 weeks) and are assessed regularly through Week 26 for blood counts, kidney function, TMA response, and safety.

Questions you could ask

These questions are suggestions for a conversation with the study team or your own clinician, not advice.

The listed sites are in Japan. Is any of them reachable for me, and does the study help with travel?
Which of the eligibility criteria would need to be checked with tests before I could join?

More on atypical hemolytic uremic syndrome

Clinical trials13 trials listed for atypical hemolytic uremic syndromeEvery trial the registry lists for atypical hemolytic uremic syndrome, with recruitment status, phase and sites, updated from ClinicalTrials.gov.See all trials →Research updatesWhat changed in atypical hemolytic uremic syndrome researchLatest monthly update: September 2026. Includes: Ravulizumab and labs. New research summarized each month in plain language, with links to every source paper.Read the latest update →

Important dates

Study start: Dec 19, 2025
Primary completion: Jun 25, 2027 (estimated)
Study completion: Jun 25, 2027 (estimated)
Target enrollment: 20 participants (estimated)
Last updated on registry: Apr 20, 2026
Data verified: Oct 10, 2026

Sponsor and research team

The lead sponsor funds and oversees the trial. A pharmaceutical or biotech company sponsor typically means the study is testing that company's drug or device; a hospital, university, or government agency usually indicates investigator-initiated or publicly funded research.

Lead sponsor: Alexion Pharmaceuticals, Inc.

Central study contact

If you're interested in participating, the central contact can answer general questions about the study — including eligibility requirements and how to find a recruiting site near you. Actual eligibility is determined by the site's medical team.

Alexion Pharmaceuticals, Inc. (Sponsor) 📞 1-855-752-2356 ✉ clinicaltrials@alexion.com

Participating sites (12)

Research SiteNot Yet Recruiting
Bunkyō City, 113-8655 · Japan
Research SiteNot Yet Recruiting
Hirakata-shi, 573-1191 · Japan
Research SiteRecruiting
Iruma-Gun, 350-0495 · Japan
Research SiteNot Yet Recruiting
Kyoto, 602-8566 · Japan
Research SiteNot Yet Recruiting
Matsumoto-shi, 390-8621 · Japan
Research SiteNot Yet Recruiting
Miyazaki, 889-1692 · Japan
Research SiteRecruiting
Nagoya, 466-8650 · Japan
Research SiteNot Yet Recruiting
Nara, 630-8581 · Japan
Research SiteNot Yet Recruiting
Nerima-ku, 177-8521 · Japan
Research SiteNot Yet Recruiting
Sapporo, 060-8638 · Japan

Terms used on this page · explanations by MedicalUpdates.ai

primary objective: The main result the study is designed to measure and report on. Other results, called secondary outcomes, are also collected.
baseline: Measurements taken at the start of the study, before any study treatment, so that later results can be compared with them.
prior treatment: Treatment a person has already had for the condition. A 'line of therapy' is one course of treatment; studies often require, or limit, the number of prior lines.
enrolment: The number of participants a study plans to include, or has included. 'Estimated' means the planned number; 'actual' means the number who joined.
Inclusion Criteria: The conditions a person must meet to be considered for the study, for example a confirmed diagnosis, an age range or a test result.
Exclusion Criteria: The conditions that rule a person out even if they meet the inclusion criteria, for example other illnesses, certain medicines or pregnancy.

The study record on this page is reproduced from ClinicalTrials.gov, a database of the U.S. National Library of Medicine, where it was submitted by the study sponsor. MedicalUpdates.ai does not own this content, is not affiliated with or endorsed by ClinicalTrials.gov, NIH, or the U.S. Government, and does not verify the record. Plain-language notes, the glossary and the questions above are added by this site; text in the boxes marked "AI summary" was written by an AI model and may contain errors. Registry records change over time. Check the original record for the current version and discuss eligibility or participation with a qualified healthcare professional.

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