Complete this brief questionnaire

Check eligibility

This study is looking for individuals (ages 18-80) with immune-mediated thrombotic thrombocytopenic purpura (iTTP).  Sanofi believes that everyone should have the opportunity to participate in clinical trials, especially those that have been historically under-represented.  


Complete a brief questionnaire to help determine if you may qualify to be referred to a site recruiting in your area for further evaluation for potential participation in this clinical study.


Am I eligible?
Immune-mediated thrombotic thrombocytopenic purpura (iTTP), also known as acquired thrombotic thrombocytopenic purpura (aTTP), is a rare blood disorder.  The current rate of occurrence for TTP is about 3.7 cases per million people each year.  This serious blood disorder can cause:  clots blocking blood flow, oxygen and nutrients to vital organs, bleeding inside the body (internal bleeding), bleeding underneath the skin or from the surface of the skin creating spots or red areas (purpura) and death. 

Patients with iTTP have increased amounts of an unusual protein called von Willebrand factor.  This protein has a particular effect on platelets, causing them to stick together and form blood clots throughout the body.  Overall, this leaves fewer platelets in the body to prevent and stop bleeding.   

Treatment of iTTP includes:  Cablivi (caplacizumab) in combination with therapeutic plasma exchange (TPE) and immunosuppression.  During TPE, a machine is used to replace the patient's plasma with healthy plasma in the blood.   

What is the purpose of the study?

The purpose of this study is to evaluate the safety and effectiveness of caplacizumab and immunosuppressive drugs without TPE by measuring the proportion of patients who achieve remission (no signs and symptoms of iTTP and iTTP related blood markers are in the normal range) without requiring therapeutic plasma exchange. 

Am I eligible?

What is the investigational medication? 

Cablivi (caplacizumab) is currently approved and marketed for the treatment of adult patients with iTTP, in combination with therapeutic plasma exchange and immunosuppressive therapy.  Caplacizumab is a small antibody which has been designed to attach to von Willebrand factor in a way that stops it acting on platelets. As a result, platelet levels in the blood should increase towards normal because they are no longer taken to form clots.  

All participants will receive caplacizumab.  Caplacizumab will be given once into the blood vessels (intravenously) at the beginning of the study and then under the skin (subcutaneously) as an injection in the abdomen daily.  During hospitalization the study staff will administer the injection. Before discharge from the hospital, you will receive training on how to perform the injection at home.  

Study Information

How long is the study?

A maximum of 24 weeks (about six months).  Treatment is up to 12 weeks with an additional 12-week follow-up.  

How many study visits will there be?  

A maximum of 15 visits to the study clinic, following initial hospitalization.

How many people are in the study?  

This study will enroll approximately 61 participants in sites across North America and Europe.

What is expected if I qualify and decide to participate?

Review and sign the informed consent to participate.  

Attend all study visits and complete the study assessments.

Complete an electronic diary daily.  

Hospitalized during the first part of your illness, where you will you receive the investigational medication intravenous (into the blood vessels) followed by daily subcutaneous injections (under the skin) of caplacizumab. Once your condition has stabilized, the study doctor will make a decision if it is safe to be discharged from the hospital.

Perform daily self-injections at home.

Report immediately any side effects that you may experience, changes in medications or hospitalizations to your doctor / study staff.

Abstain from strenuous exercise during study participation for 4 weeks after the last dose.

Tell the doctor / study staff if you are thinking about stopping the study treatment or leaving the study.

Agree not to join another research study throughout the duration of the study.

FAQ on SanofiStudies.com

Is there a cost to participate?  

No, all things study-related are provided, including study-related exams, study-related medications and other study-related medical care.  There is no insurance required to participate.  All study-related medical care will be explained.  Study-related exams may include:  


  • Physical exam 
  • Neurologic assessments (tests sensory and motor responses) 
  • Cognitive assessment (test of orientation, attention, calculation, recall, language, and motor skills) 
  • Bleeding assessment (symptoms of bleeding in any part of your body) 
  • Vital signs (blood pressure, heart rate, temperature)  
  • Blood tests
  • Pregnancy tests (if applicable)  
  • Electrocardiogram (ECG, records the electrical activity of the heart over a period of time using electrodes placed on the skin)  

This study may offer compensation for travel. 

Can I speak with someone if I have questions?

Yes, after you complete the online questionnaire and give permission to be contacted, a study representative will contact with you. You can ask questions at any time, before deciding to participate and during study conduct.

Find a site near you

Reese JA, Muthurajah DS, Kremer Hovinga JA, Vesely SK, Terrell DR, George JN. Children and Adults With Thrombotic Thrombocytopenic Purpura Associated With Severe, Acquired Adamts13 Deficiency: Comparison Of Incidence, Demographic and Clinical Features. Pediatr Blood Cancer. 2013:60(10):1676-82. 7. Page EE, 

Kremer Hovinga JA, Terrell DR, Vesely SK, George JN. Thrombotic thrombocytopenic purpura: diagnostic criteria, clinical features, and long-term outcomes from 1995 through 2015. Blood Adv. 2017;1(10):590-600.


Version 1.0, 16Aug2022