Primary immune thrombocytopenia (ITP) MedDRA version: 23.0 Level: LLT Classification code 10083843 Term: Primary immune thrombocytopenia System Organ Class: 100000004851
Conditions
Sponsors
argenx BV
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Ability to understand the requirements of the trial and provide written informed consent (including consent for the use and disclosure of research-related health information), willing and able to comply with the trial protocol procedures (including attending the required trial visits). 2. Male or female, aged =18 years at the time the informed consent form (ICF) is signed. Exceptions are made for the Republic of South Korea and Taiwan where, according to local regulatory requirements, legal age is reached at 19 years and 20 years, respectively. 3. Confirmed diagnosis of primary ITP made at least 3 months before randomization and based on the American Society of Hematology Criteria, and no known etiology for thrombocytopenia. 4. Diagnosis supported by a response to a prior ITP therapy (other than TPO-RAs), in the opinion of the investigator. 5. Mean platelet count of =65 years) yes F.1.3.1 Number of subjects for this age range 28
Exclusion criteria
Exclusion criteria: 1. Secondary ITP/thrombocytopenia associated with another condition, eg, lymphoma, chronic lymphocytic leukemia, viral infection, hepatitis, induced or alloimmune thrombocytopenia, thrombocytopenia associated with myeloid dysplasia, or hematopoietic stem cell transplant. 2. Use of anticoagulants (eg, vitamin K antagonists, direct oral anticoagulants) within 4 weeks prior to randomization. 3. Use of any transfusions within 4 weeks prior to randomization. 4. Use of Ig (IV, SC, or intramuscular route) or plasmapheresis (PLEX) within 4 weeks prior to randomization. 5. Use of romiplostim within 4 weeks prior to randomization. 6. Undergone splenectomy less than 4 weeks prior to randomization. 7. Use of an investigational product within 3 months or 5 half-lives (whichever is longer) before the first dose of the IMP. 8. Use of any monoclonal antibody or Fc fusion proteins, other than those previously indicated, within 6 months before the first dose of the IMP (eg, anti-CD20). 9. At the screening visit, clinically significant laboratory abnormalities as follows: • Hemoglobin =9 g/dL - OR – • International normalized ratio >1.5 or activated partial thromboplastin time >1.5×upper limit of normal - OR – • total IgG level <6 g/L 10. History of malignancy unless deemed cured by adequate treatment with no evidence of recurrence for =3 years before the first administration of IMP. Participants with the following cancer can be included at any time: a. Adequately treated basal cell or squamous cell skin cancer b. Carcinoma in situ of the cervix c. Carcinoma in situ of the breast or d. Incidental histological finding of prostate cancer (TNM stage T1a or T1b) 11. Uncontrolled hypertension, defined as a repeated elevated blood pressure exceeding 160 mmHg (systolic) and/or 100 mmHg (diastolic) despite appropriate treatments. 12. History of any major thrombotic or embolic event (eg, myocardial infarction, stroke, deep venous thrombosis, or pulmonary embolism) within 12 months prior to randomization. 13. History of coagulopathy or hereditary thrombocytopenia or a family history of thrombocytopenia. 14. Evidence of an active clinically significant bleeding of an organ or internal mucosal bleeding, other than expected in ITP, that warrants emergent treatment or therapeutic procedure based on the investigator’s judgment (eg, intracranial hemorrhage, pulmonary hemorrhage, bleeding with ongoing need for packed red blood cell transfusion). 15. Estimated high risk of a clinically significant bleeding of an organ or internal mucosal bleeding, other than expected in ITP, that warrants emergent treatment or therapeutic procedure according to the investigator’s judgment. 16. Clinical evidence of other significant serious diseases, have had a recent major surgery, or who have any other condition in the opinion of the investigator, that could confound the results of the trial or put the participant at undue risk. 17. Positive serum test at screening for an active viral infection with any of the following conditions: a. Hepatitis B virus (HBV) that is indicative of an acute or chronic infection, unless associated with a negative HBV DNA test (https://www.cdc.gov/hepatitis/HBV/PDFs/SerologicChartv8.pdf). b. Hepatitis C virus (HCV) based on HCV-antibody assay (unless associated with a negative HCV RNA test). c. Human immunodeficiency virus (HIV) based on test results that are associated with an acquired immunodeficiency syndrome (AIDS)-defining condition or a CD4 count =
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Main Objective: To evaluate the efficacy of efgartigimod PH20 SC compared to placebo PH20 SC in achieving a sustained platelet count response in patients with chronic primary ITP, with a sustained platelet count response defined as platelet counts of =50×10^9/L for at least 4 of the 6 visits between week 19 and week 24 of the trial ;Secondary Objective: • To evaluate the efficacy of efgartigimod PH20 SC compared to placebo PH20 SC in overall platelet count response • To evaluate the incidence and severity of bleeding events while receiving treatment with efgartigimod PH20 SC compared to placebo PH20 SC •To evaluate the safety and tolerability of efgartigimod PH20 SC administered qw or every other week (q2w) compared to placebo PH20 SC • To evaluate the use of rescue treatment and changes in concurrent ITP therapy while receiving treatment with efgartigimod PH20 SC compared to placebo PH20 SC • To evaluate the effects of efgartigimod PH20 SC treatment on quality-of-life (QoL) measures and patient-reported outcomes (PRO) compared to placebo PH20 SC • To assess the immunogenicity of efgartigimod and rHuPH20 • To assess the pharmacokinetics (PK) of efgartigimod PH20 SC • To assess the pharmacodynamic (PD) effects of efgartigimod PH20 SC;Primary end point(s): Proportion of patients with chronic ITP with a sustained platelet count response defined as achieving platelet counts of =50×10^9/L for at least 4 of the 6 visits between week 19 and week 24 of the trial;Timepoint(s) of evaluation of this end point: Up to 5 weeks (between week 19 –24) | — |
Secondary
| Measure | Time frame |
|---|---|
| Secondary end point(s): 1. Extent of disease control defined as the number of cumulative weeks over the planned 24-week treatment period with platelet counts of =50×10^9/L in the chronic ITP population (Key Secondary Endpoint 1) 2. Proportion of patients in the overall population (chronic and persistent ITP) with a sustained platelet count response defined as achieving platelet counts of =50×10^9/L for at least 4 of the 6 visits between week 19 and week 24 (Key Secondary Endpoint 2) 3. Proportion of patients in the overall population achieving platelet counts of =50×10^9/L for at least 6 of the 8 visits between week 17 and 24 of the trial (Key Secondary Endpoint 3) 4. Proportion of patients in the overall population with overall platelet response defined as achieving a platelet count of =50×10^9/L on at least 4 occasions at any time during the 24-week treatment period 5. Extent of disease control defined as the number of cumulative weeks until week 12 with platelet counts of =50×10^9/L in the overall population 6. Proportion of patients in the overall population with overall platelet response defined as achieving a platelet count of =50×10^9/L on at least 4 occasions at any time until week 12 7. Mean change from baseline in platelet count at each visit in the overall population 8. Time to response defined as the time to achieve 2 consecutive platelet counts of =50×10^9/L in the overall population 9. The number of cumulative weeks over the planned 24-week treatment period with platelet counts of =30×10^9/L and =20×10^9/L above baseline in the overall population 10. In patients with baseline platelet count of <15×10^9/L, the number of cumulative weeks over the planned 24-week treatment period with platelet counts of =30×10^9/L and =20×10^9/L above baseline in the overall population 11. Incidence and severity of the World Health Organization (WHO)-classified bleeding events in the overall population (Key Secondary Endpoint 4) 12. Incidence and severity of AEs, AEs of | — |
Countries
Argentina, Australia, Bulgaria, Chile, China, Colombia, Denmark, France, Georgia, Germany, Greece, Ireland, Israel, Italy, Japan, Jordan, Korea, Republic of, Mexico, New Zealand, Norway, Peru, Poland, Portugal, Romania, Russian Federation, Serbia, South Africa, Spain, Taiwan, Thailand, Tunisia, Turkey, United Kingdom, United States
Contacts
Public ContactRegulatory
argenx BV
Outcome results
None listed