A Study to Learn More About the Treatment of People With Congenital Thrombotic Thrombocytopenic Purpura (cTTP) Who Received Recombinant ADAMTS13 (rADAMTS13) as Part of the Early Access Program

Treatment and Management of Patients With Congenital Thrombotic Thrombocytopenic Purpura (cTTP): An International, Multi-center Retrospective Chart Review of Patients in the Early Access Program (EAP) Treated With Recombinant ADAMTS13 (rADAMTS13)

Congenital thrombotic thrombocytopenic purpura (cTTP) is a rare blood disorder that some people are born with. It is caused by inherited changes in the ADAMTS13 gene that reduce the body's ability to produce the ADAMTS13 enzyme. ADAMTS13 normally cleaves ultra-large multimers of a protein called von Willebrand factor (VWF). In cTTP, low ADAMTS13 activity allows these ultra-large VWF multimers to build up and promote blood clot formation in small blood vessels. These clots can restrict blood flow to vital organs and lead to serious complications.

Recombinant ADAMTS13 (rADAMTS13) is a manufactured form of human ADAMTS13 designed to replace the missing enzyme and restore ADAMTS13 activity.

This study aims to describe the impact of cTTP on participants before and after treatment with rADAMTS13. It will also evaluate participants' health outcomes after treatment and describe treatment patterns before and after rADAMTS13, including whether treatment was used to prevent or treat TTP episodes, how often it was given, the amount received, and others. In addition, the study will describe pregnancies and outcomes for the mother and baby before and during treatment with rADAMTS13.

Only data already available in the medical records of the people who received rADAMTS13 through Takeda's early access program (EAP) for cTTP will be collected and reviewed in this study.

Study Overview

• Status: Not yet recruiting
• Conditions: Thrombotic Thrombocytopenic Purpura (TTP)
• Intervention / Treatment: Other: No Intervention

• Study Type: Observational
• Enrollment (Estimated): 94

Contacts and Locations

• Study Contact: Name: Takeda Contact; Phone Number: +1-877-825-3327; Email: medinfoUS@takeda.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult and pediatric participants treated with rADAMTS13 via the EAP at participating centers will be included in this study.

Description

Inclusion criteria for the rADAMTS13 EAP are:

• Participants of any age can participate who have a confirmed diagnosis of severe congenital ADAMTS13 deficiency or cTTP.
• Participants must be on preventative or prophylactic treatment for cTTP or must have had at least one TTP event in the past.
• Participants must have no other treatment options available (this includes other clinical studies for cTTP).

The inclusion criteria for this retrospective chart review are:

• Pediatric and adult participants (no age restrictions) with cTTP, treated with rADAMTS13 via the EAP, who received at least two administrations of rADAMTS13 and who have provided consent (or the legal guardians) to participate in this retrospective chart review.
• As per local regulations, evidence of a personally signed (or signed by a legally acceptable representative) and dated informed consent form/informed assent form (ICF/IAF) indicating that the participant (or their legal guardian) has been informed of all pertinent aspects of the retrospective chart review or an approval to process data without informed consent granted by an institutional review board/independent ethics committee (IRB/IEC)) Participants included in the EAP who were/are transitioned to the commercially available product will have their data abstracted for the duration of their participation in the EAP as well as when they received the commercially available product until the end of chart abstraction.

There are no additional exclusion criteria for this chart review.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Participants with cTTP; Data of participants who have received rADAMTS13 for the treatment of cTTP will be collected retrospectively from electronic medical records (eMR) for before (up to 6 months) and after initiation of rADAMTS13 treatment. Participant enrollment and data collection for this study is expected to be completed by the last quarter of 2026.	Other: No Intervention; This is a non-interventional study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of cTTP Acute and Subacute Episodes Before and During Treatment with rADAMTS13	Acute episodes will be defined as those with clinically overt features of thrombotic microangiopathy, including thrombocytopenia, microangiopathic hemolytic anemia, and/or organ dysfunction, often requiring urgent therapeutic intervention. Subacute or non-overt episodes will be defined as episodes with laboratory evidence of thrombocytopenia or hemolysis without significant clinical symptoms or organ involvements, often detected on routine monitoring.	Up to 6 months prior to the initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Changes in Hematological Measures (Platelet Count) Before and During Treatment with rADAMTS13	Changes in hematological measures like platelet count (thrombocytopenia) will be reported.	Up to 6 months prior to the initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Changes in Hematological Measures (Microangiopathic Hemolytic Anemia [MAHA]) Before and During Treatment with rADAMTS13	Changes in hematological measures like MAHA will be reported.	Up to 6 months prior to the initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Changes in Biochemical Measures (Lactate Dehydrogenase [LDH]) Before and During Treatment with rADAMTS13	Changes in Biochemical measures like LDH will be reported.	Up to 6 months prior to the initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Changes in Biochemical Measures (Proteinuria) Before and During Treatment with rADAMTS13	Changes in Biochemical measures like Proteinuria will be reported.	Up to 6 months prior to the initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Changes in Biochemical Measures (Serum creatinine) Before and During Treatment with rADAMTS13	Changes in Biochemical measures like serum creatinine will be reported.	Up to 6 months prior to the initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Changes in Biomarker Measures Before and During Treatment with rADAMTS13	Changes in biomarker measures like ADAMTS13 activity level, total ADAMTS13 neutralizing/binding antibodies will be reported.	Up to 6 months prior to the initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Number of Participants with cTTP Symptoms Before and During Treatment with rADAMTS13	Number of participants with cTTP symptoms like abdominal pain, fatigue/lethargy, fever, bruising/purpura, neurological symptoms/stroke episodes, renal signs, thrombocytopenia, upper respiratory tract infections, headache/migraine, dizziness, diarrhea, nausea will be assessed using participant's electronic medical record (eMR).	Up to 6 months before initiation of rADAMTS13 administration and continuing during rADAMTS13 administration

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Reasons for rADAMTS13 Early Access Request	Number of reasons for early access request will be described.	Up to 6 months before initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Number of Treatment Initiation Characteristics at the First Dose of rADAMTS13	Treatment initiation characteristics includes first rADAMTS13 treatment, participants weight at initiation of treatment, starting dose of rADAMTS13, other dose than specified in summary of product characteristics for prophylaxis or acute treatment, starting prophylaxis dose, frequency and duration will be reported.	From first dose of rADAMTS13 until EAP discontinuation (up to 6 months)
Number of Treatment Changes During rADAMTS13 Treatment	Treatment changes during rADAMTS13 treatment (for each treatment episode) includes treatment purpose, treatment dates, location, doses and duration, any change(s) to dose, dosing frequency or duration, including dates and the reason(s), additional cTTP prophylaxis treatments will be reported.	From first dose of rADAMTS13 until EAP discontinuation (up to 6 months)
Peak Activity Level of ADAMTS13	Peak ADAMTS13 activity level i.e., highest level post-infusion will be reported.	Up to 6 months before initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Trough Activity Level of ADAMTS13	Trough ADAMTS13 activity level i.e., lowest level before next dose will be reported.	Up to 6 months before initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Time of Sample Collection Relative to Infusion	Time of sample collection relative to infusion (1-hour pre infusion, 6 hours post infusion etc) will be reported.	Up to 6 months before initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Duration of Treatment and EAP Discontinuation With rADAMTS13	Duration of treatment and EAP Discontinuation with rADAMTS13 will be reported.	Up to end of treatment (up to 18 months)
Number of Reasons for Treatment and EAP Discontinuation Before and During Treatment with rADAMTS13	Number of reasons for treatment and EAP discontinuation before and during treatment with rADAMTS13 will be reported.	Up to end of treatment (up to 18 months)
Number of Participants Showing Response as per Laboratory Assessments After Treatment with rADAMTS13	Number of participants showing response as per laboratory assessments after treatment with radamts13 will be reported.	After rADAMTS13 administration
Number of Instances of Pregnancy and its Corresponding Outcome Before and During Treatment with rADAMTS13	Number of instances of pregnancy and its corresponding Outcome, including pregnancies coinciding with exposure to rADAMTS13 will be reported.	Up to 6 months prior to the initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Duration of Infusion During Treatment with rADAMTS13	Duration of infusion during treatment with rADAMTS13 will be reported.	From First dose of rADAMTS13 until EAP discontinuation (Up to 6 months)
Number of Days Spent in Hospital	Number of days spent by participants in hospital will be reported.	From first dose of rADAMTS13 until EAP discontinuation (Up to 6 months)
Number of Treatment Related Reasons for Hospitalization	Number of treatment related reason for hospitalization will be reported.	From first dose of rADAMTS13 until EAP discontinuation (Up to 6 months)

Collaborators and Investigators

• Sponsor: Takeda
• Investigators: Study Director: Study Director, Takeda

Publications and helpful links

Helpful Links

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• Click here for more information about this trial in easy-to-understand language.

Study record dates

Study Major Dates

• Study Start (Estimated): July 31, 2026
• Primary Completion (Estimated): September 30, 2026
• Study Completion (Estimated): September 30, 2026

Study Registration Dates

• First Submitted: January 28, 2026
• First Submitted That Met QC Criteria: February 18, 2026
• First Posted (Actual): February 24, 2026

Study Record Updates

• Last Update Posted (Actual): July 10, 2026
• Last Update Submitted That Met QC Criteria: July 9, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Drug Therapy
• Additional Relevant MeSH Terms: Cytopenia; Pathologic Processes; Hemorrhage; Skin Manifestations; Hematologic Diseases; Blood Coagulation Disorders; Blood Platelet Disorders; Thrombotic Microangiopathies; Purpura, Thrombocytopenic; Purpura; Thrombocytopenia; Thrombophilia; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Hemic and Lymphatic Diseases; Purpura, Thrombotic Thrombocytopenic
• Other Study ID Numbers: TAK-755-4008

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Takeda provides access to the de-identified individual participant data (IPD) for eligible studies to aid qualified researchers in addressing legitimate scientific objectives (Takeda's data sharing commitment is available on https://clinicaltrials.takeda.com/takedas-commitment?commitment=5). These IPDs will be provided in a secure research environment following approval of a data sharing request, and under the terms of a data sharing agreement.
• IPD Sharing Access Criteria: IPD from eligible studies will be shared with qualified researchers according to the criteria and process described on https://vivli.org/ourmember/takeda/. For approved requests, the researchers will be provided access to anonymized data (to respect patient privacy in line with applicable laws and regulations) and with information necessary to address the research objectives under the terms of a data sharing agreement.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes