An observational study in Bleeding Disorder, sponsored by University Hospital, Geneva. Recruiting at 7 sites in Switzerland. Open to participants aged 16 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-04-29.
Sponsored by University Hospital, Geneva · Observational
The goal of this prospective cohort is to identified specific biological patterns in patients with a bleeding of unknown cause and to study the specific mechanisms of the bleeding disorder for each subset of patients.
Patients with bleeding of unknown cause are included. At baseline, blood will be drawn to evaluate the hemostatic profile. Findings are compared to a control group of healthy individuals. Patients and controls are followed for 3 years.
361 studies on the registry are indexed under Hemostatic Disorders; 65 are open to participants now.
This study's planned enrollment of 400 is above the median of 120 across 174 observational studies indexed under Hemostatic Disorders.
Browse Hemostatic Disorders studies →University Hospital, Geneva is the lead sponsor of 379 studies on the registry; 70 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Women and men aged 16-65 years who have been diagnosed as patients with bleeding of unknown cause Women and men aged 16-65 years without bleeding tendency
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.
Exclusion Criteria:
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.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients with bleeding of unknown cause
Diagnostic Test: Thrombin generation · Diagnostic Test: Fibrinolysis · Diagnostic Test: Fibrin clot structure · Diagnostic Test: Coated platelets
Healthy voluntaries without bleeding tendency
Diagnostic Test: Thrombin generation · Diagnostic Test: Fibrinolysis · Diagnostic Test: Fibrin clot structure · Diagnostic Test: Coated platelets
Measurement of thrombin generation by ST Genesia
Measurement of fibrinolysis by Lysis Timer
Measurement of fibrin polymerisation and permeability
Measurement of coated platelets by flow cytometry
Fibrin clot polymerisation
maximal absorption (optical density)
Time frame: At inclusion
Fibrin clot permeability
darcy coefficient (ks, cm2)
Time frame: At inclusion
Fibrinolysis
Clot lysis time (min)
Time frame: At inclusion
Thrombin generation
Endogenous thrombin potential (ETP, nM x min)
Time frame: At inclusion
Coated platelets
Absolute number of coated platelets
Time frame: At inclusion
Fibrinogen gamma' levels
Ratio fibrinogen gamma'/total fibrinogen (%)
Time frame: At inclusion
Scan electron microscopy
Fibrin fiber diameter (nm)
Time frame: At inclusion
Clot retraction
Ratio clot weight/serum extruded (%)
Time frame: At inclusion
Plasmin generation
Plasmin (nM)
Time frame: At inclusion
Fibrin clot formation (thrombodynamics)
Initial rate of clot growth (μM/min)
Time frame: At inclusion
Major bleeding episodes
Incidence of major bleeding
Time frame: Three years
Non-major bleeding episodes
Incidence of clinically relevant non-major bleeding
Time frame: Three years
Health related quality of life
SF36 questionnaire, 0 - 100 (high score, better outcome)
Time frame: three years
International Society Thrombosis Hemostasis Bleeding assessment tool
ISTH BAT score, 0 - 56 (high score, worse outcome)
Time frame: three years
Started Apr 2023 (actual). Primary completion is estimated for Jun 2026, 38 months after the start.
Of 98 non-industry observational studies under Hemostatic Disorders, half reached primary completion within 25 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 57. This study's planned 38 months is above that.
Counting every sponsor, half of 108 studies reached it within 24 months; a quarter within 9 and three quarters within 56.
How these figures are worked out, and which studies are left out of them.
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