A

Not Applicable

• Conditions: Congenital hemophilia A and acquired hemophilia A

• Registration Number: JPRN-jRCT1031230480
• Lead Sponsor: Keiji Nogami

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2023-11-25
• Last Update Posted: 22 January 2024

Recruitment & Eligibility

• Status: Pending
• Sex: All
• Target Recruitment: 50

Inclusion Criteria

Patients who have submitted blood samples to the plasma emicizumab concentration measurement program (hereinafter, Measurement Program) and will be collected blood samples prospectively after study enrollment.
1) Informed consent to participate in the study has been obtained from the patient personally or from a legal representative using the Informed Consent Form. If possible, assent to participate in the study will be obtained from pediatric patients personally using the Informed Assent Form.
2) Diagnosis of congenital hemophilia A or acquired hemophilia A at the time of enrollment.
3) Investigator have confirmed both of the following conditions at the time of blood sample submission to the Measurement Program prior to enrollment.
a. Recieving emicizumab in accordance with the indications and dosage and administration of the package insert.
b. Suspect of having a decreased plasma emicizumab concentration, as evidenced by prolonged APTT and increased bleeding frequency, etc.

Patients who have been stored blood samples of the Measurement Program at the central laboratory and will not be collected new blood samples after study enrollment.
1) Patients who have not indicated their refusal during the period when the documents regarding the clinical study and use of existing samples are posted on the website of the medical institution, etc.
2) Diagnosis of congenital hemophilia A or acquired hemophilia A at the time of initial sample submission to the Measurement Program.
3) Blood samples submitted to the Measuremtn Program are stored at the central laboratoy, and investigator have confirmed both of the following conditions at the time of blood sample submission to the Measurement Program.
a. Recieving emicizumab in accordance with the indications and dosage and administration of the package insert.
b. Suspect of having a decreased plasma emicizumab concentration, as evidenced by prolonged APTT and increased bleeding frequency, etc.

Exclusion Criteria

1) Inherited or acquired bleeding disprder other than congenital hemophilia A and acquired hemophilia A
2) In the judge of the investigator, patient would be unsuitable for study participation

Study & Design

• Study Type: Observational
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
The following endpoints will be described in congenital hemophilia A and aquired hemophilia A patients who are suspected of having decreased plasma emicizumab concentrations, as evidenced by prolonged APTT and increased bleeding frequency, etc., and who have tested positive for anti-emicizumab antibodies<br>APTT<br>Anti-emicizumab antibodies (antibody titer and presence of neutralizing activity)<br>- Plasma emicizumab concentration<br>- FVIII activity (emicizumab non-response, one-stage clotting assay of emicizumab-neutralizing activity)<br>- FVIII activity (emicizumab response, chromogenic assay using human coagulation factor)<br>- FVIII inhibitor titer<br>- Clot waveform analysis

Secondary Outcome Measures

Name	Time	Method
The following endpoints will be described in congenital hemophilia A and aquired hemophilia A patients who are suspected of having decreased plasma emicizumab concentrations, as evidenced by prolonged APTT and increased bleeding frequency, etc., and who have tested negative for anti-emicizumab antibodies<br>- APTT<br>- Plasma emicizumab concentration<br>- FVIII activity (emicizumab non-response, one-stage clotting assay of emicizumab-neutralizing activity)<br>- FVIII activity (emicizumab response, chromogenic assay using human coagulation factor)<br>- FVIII inhibitor titer<br>- Clot waveform analysis<br> Changes over time in anti-emicizumab antibody titers, coagulation tests and clinical findings in anti-emicizumab antidody-positive patients.<br>Characteristic analysis of anti-emicizumab antibodies.<br>Exploratory study on future hemophilia therapeutic drug.