An observational study in Glanzmann Thrombasthenia, sponsored by Rockefeller University. Recruiting at 1 site in United States. Per ClinicalTrials.gov, last updated 2025-10-20.
Sponsored by Rockefeller University · Observational
Blood contains red blood cells, white blood cells, and platelets, as well as a fluid portion termed plasma. We primarily study blood platelets, but sometimes we also analyze the blood of patients with red blood cell disorders (such as sickle cell disease), white blood cell disorders, and disorders of the blood clotting factors found in plasma.
Blood platelets are small cell fragments that help people stop bleeding after blood vessels are damaged. Some individuals have abnormalities in their blood platelets that result in them not functioning properly. One such disorder is Glanzmann thrombasthenia. Most such patients have a bleeding disorder characterized by nosebleeds, gum bleeding, easy bruising (black and blue marks), heavy menstrual periods in women, and excessive bleeding after surgery or trauma. Our laboratory performs advanced tests of platelet function and platelet biochemistry. If we find evidence that a genetic disorder may be responsible, we analyze the genetic material (DNA and RNA) from the volunteer, and when possible, close family members to identify the precise defect.
After volunteers and family members agree to participate, they are seen in the Outpatient Research Center by the Principal Investigator or another physician. A detailed history is obtained, a physical examination is performed, and blood is obtained for further tests. Occasionally patients and family members are requested to return for additional tests. If an abnormality is identified with tests conducted in our research laboratory, we advise the volunteer to have the studies repeated in a laboratory certified to conduct tests on patients.
955 studies on the registry are indexed under Thrombosis; 171 are open to participants now.
This study's planned enrollment of 60 is below the median of 173 across 384 observational studies indexed under Thrombosis.
Browse Thrombosis studies →Rockefeller University is the lead sponsor of 123 studies on the registry; 3 are open to participants now.
Of its 14 completed or terminated interventional studies of FDA-regulated products, 6 (43%) have results posted.
Counted across the registry records on this site, refreshed daily.
For normal volunteers, we recruit from laboratory personnel and other volunteers from the NYC area. Patients with platelet disorders, coagulation disorders, or white blood cell disorders, are recruited from among patients referred by other physicians to the P.I. for assessment or via the internet.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
A. Normal Healthy Volunteers:
B. Patients with Glanzmann thrombasthenia or their relatives, inherited qualitative and/or quantitative disorders, inherited disorders of white blood cells, inherited disorders of coagulation (including von Willebrand disease):
Exclusion Criteria:
A. Normal Healthy Volunteers:
B. Patients with Glanzmann thrombasthenia or their relatives, inherited qualitative and/or quantitative platelet disorders, inherited disorders of white blood cells, inherited disorders of coagulation (including von Willebrand disease).
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.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Normal, healthy volunteers 18 years of age or older of either sex and any ethnic background
Patients with Glanzmann thrombasthenia or their relatives, inherited qualitative and/or quantitative platelet disorders, inherited disorders of white blood cells, inherited disorders of coagulation
Platelet aggregation
The initial slope of the increase in light transmission after an agonist is added to a cuvette containing platelet-rich plasma.
Time frame: minutes
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