Evaluating platelet responses to caplacizumab in treating aTTP

Platelet Response to Caplacizumab in the Treatment of Acquired Thrombotic Thrombocytopenic Purpura

University of Cologne · NCT05876221

This study looks at how well patients with aTTP respond to the treatment caplacizumab by checking their platelet counts to help doctors make better treatment decisions.

Quick facts

Study typeObservational
Enrollment160 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of Cologne (other)
Drugs / interventionscaplacizumab
Locations1 site (Cologne)
Trial IDNCT05876221 on ClinicalTrials.gov

What this trial studies

This observational study aims to assess how patients with acquired thrombotic thrombocytopenic purpura (aTTP) respond to caplacizumab, a treatment that blocks platelet binding sites on VWF-multimers. By analyzing platelet count dynamics, the study seeks to identify predictive parameters that can help clinicians avoid misinterpretation of platelet responses, which could lead to inappropriate treatment adjustments. The study will involve a retrospective analysis of a large cohort of patients who have received caplacizumab. The goal is to improve understanding of platelet behavior in response to this therapy.

Who should consider this trial

Good fit: Ideal candidates include adults over 18 with a confirmed diagnosis of autoimmune aTTP who have received caplacizumab.

Not a fit: Patients with hereditary thrombotic thrombocytopenic purpura will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to better management of aTTP, reducing the risk of over- or undertreatment.

How similar studies have performed: While this approach is novel in its specific focus on caplacizumab's effects on platelet dynamics, similar studies have shown promise in understanding treatment responses in aTTP.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Confirmed diagnosis of autoimmune thrombotic thrombocytopenic purpura
* Treatment with at least a single dose of caplacizumab, either i.v. or s.c.
* Male or female patients older than 18 years of age

Exclusion Criteria:

* Hereditary thrombotic thrombocytopenic purpura

Where this trial is running

Cologne

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Acquired Thrombotic Thrombocytopenic Purpura, caplacizumab, platelet responses, aTTP, iTTP

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.