An observational study in Thrombotic Thrombocytopenic Purpura (TTP), sponsored by Takeda. Recruiting at 8 sites in 2 countries. Per ClinicalTrials.gov, last updated 2026-10-20.
Sponsored by Takeda · Observational
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.
67 studies on the registry are indexed under Purpura, Thrombotic Thrombocytopenic; 18 are open to participants now.
This study's planned enrollment of 94 is below the median of 156 across 27 observational studies indexed under Purpura, Thrombotic Thrombocytopenic.
Browse Purpura, Thrombotic Thrombocytopenic studies →Takeda is the lead sponsor of 1,026 studies on the registry; 89 are open to participants now.
Of its 178 completed or terminated interventional studies of FDA-regulated products, 154 (87%) have results posted.
Counted across the registry records on this site, refreshed daily.
Adult and pediatric participants treated with rADAMTS13 via the EAP at participating centers will be included in this study.
Inclusion criteria for the rADAMTS13 EAP are:
The inclusion criteria for this retrospective chart review are:
There are no additional exclusion criteria for this chart review.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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).
Time frame: Up to 6 months before initiation of rADAMTS13 administration and continuing during rADAMTS13 administration
Number of Reasons for rADAMTS13 Early Access Request
Number of reasons for early access request will be described.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: From first dose of rADAMTS13 until EAP discontinuation (Up to 6 months)
Not enrolling at this site.
Plan to share: Yes — 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.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
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.
Data sharing details ↗ · vivli.org
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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