Study to Evaluate Rilzabrutinib in Adults and Adolescents With Persistent or Chronic Immune Thrombocytopenia (ITP)

JRCT ID: jRCT2051220003

Registered date:08/04/2022

Basic Information

• Recruitment status: Recruiting
• Health condition(s) or Problem(s) studied: Immune Thrombocytopenia
• Date of first enrollment: 11/05/2022
• Target sample size: 224
• Countries of recruitment: Argentina,Japan,Australia,Japan,Austria,Japan,Brazil,Japan,Canada,Japan,Chile,Japan,France,Japan,Germany,Japan,Hungary,Japan,Israel,Japan,Italy,Japan,Republic of Korea,Japan,Mexico,Japan,Norway,Japan,Poland,Japan,Russian Federation,Japan,Singapore,Japan,Spain,Japan,Thailand,Japan,Turkey,Japan,Ukraine,Japan,United Kingdom,Japan,United States,Japan,China,Japan,Netherlands,Japan
• Study type: Interventional

Intervention(s)

Drug: Rilzabrutinib (PRN1008)
Pharmaceutical form: 400mg Caplet, Route of administration: Oral
Drug: Placebo
Pharmaceutical form: 400mg Caplet, Route of administration: Oral

Outcome(s)

Primary Outcome

1. Durable platelet response during the last 6 weeks of the 24-week blinded treatment period (not for EU and UK) [ Time Frame: 24 weeks ]
Durable platelet response is defined as a proportion of participants able to achieve platelet counts at or above 50,000/microL for >= two-thirds of at least 8 non-missing weekly scheduled platelet measurements during the last 12 weeks of the 24-week blinded treatment period in the absence of rescue therapy, provided that at least 2 non-missing weekly scheduled platelet measurements are at or above 50,000/microL.

2. for EU and UK: Proportion of adult participants able to achieve platelet counts at or above 50,000/microL for at least 8 out of the last 12 weeks of the 24-week blinded treatment period in the absence of rescue therapy [ Time Frame: 24 weeks ]

Secondary Outcome

1. Number of weeks with platelet count >= 50,000/microL OR between >= 30,000/microL and <50,000/microL and at least doubled from baseline over the 24-week blinded treatment period in the absence of rescue therapy [ Time Frame: 24 weeks ]

2. Number of weeks with platelet counts >=30,000/microL and at least doubled from baseline over the 24-week blinded treatment period in the absence of rescue therapy [ Time Frame: 24 weeks ]

3. Time to first platelet count of >= 50,000/microL OR between >=30,000/microL and <50,000/microL and doubled from baseline [ Time Frame: 24 weeks ]

4. Proportion of patients requiring rescue therapy during the 24-week blinded treatment period [ Time Frame: 24 weeks ]

5. Change from baseline on Item 10 of the ITP-Patient Assessment Questionnaire in adult patients (>=18 years) at Week 13 [ Time Frame: From baseline to Week 13 ]

6. for EU and UK: Change from baseline in Idiopathic Thrombocytopenic Purpura Bleeding Scale (IBLS) assessment at Week 25 [ Time Frame: at Week 25 ]

7. Proportion of participants who able to achieve stable platelet response, within a period of 24 weeks following initial achievement of the platelet response [ Time Frame: 24 weeks ]
Stable platelet response is defined as no 2 scheduled visits, at least 4 weeks apart, with a platelet count less than 50,000/microL, without an intervening visit with a platelet count >=50,000/microL. Initial platelet response defined as platelet count >=50,000/microL within 12 weeks of initiation of treatment with rilzabrutinib during the study.

8. Frequency and severity of Treatment Emergent Adverse Events [ Time Frame: 52 weeks of treatment, 12 months of long term extension and 4 weeks of follow up post last dose ]
Including physical examination, ECG, clinical laboratory test results, vital signs and laboratory tests (serum chemistry, hematology, except for platelet counts included in the primary efficacy endpoint)

9. Frequency and severity of bleeding TEAEs [ Time Frame: 52 weeks of treatment, 12 months of long term extension and 4 weeks of follow up post last dose ]

10. Plasma concentrations of rilzabrutinib [ Time Frame: Until 52 weeks ]

11. Change from baseline on the Symptoms, Bother and Activity domains of the ITP Patient Assessment Questionnaire (ITP-PAQ) in adult patients (>= 18 years) [ Time Frame: 52 weeks of treatment, 12 months of long term extension and 4 weeks of follow up post last dose ]
The ITP Patient Assessment Questionnaire (ITP-PAQ) is a disease-specific instrument that was designed to measure the Quality of Life (QoL) of adult patients with immune thrombocytopenia. The items employ a 4-week recall with responses recorded on 4-, 5- or 7-point Likert scales. All item scores are transformed to a 0 to 100 continuum where higher scores represent better QoL and are weighted equally to derive the scale scores.

12. Change from baseline in disease-specific QoL as measured by the Kids' ITP Tools (ITP-KIT) score in pediatric participants [ Time Frame: 52 weeks of treatment, 12 months of long term extension and 4 weeks of follow up post last dose ]
The ITP-KIT include a battery of three disease-specific instruments, a child self-report form designed to be completed by children >= 7 years, a parent proxy report form for children <7 and a parent impact form. Respondents record their disease experience based on a 1-week recall. The instrument yields a total score which is the summation of the items converted to a 0 to 100 score with higher scores indicating better disease-specific QoL.

Key inclusion & exclusion criteria

• Age minimum: >= 12age old
• Age maximum: Not applicable
• Gender: Both

Include criteria

1. Patients will be male and female with primary ITP with duration of >6 months in pediatric participants aged 12 to <18 years (pediatric participants aged 10 to <12 years will be enrolled in the EU [EEA countries] only) and duration of >3 months in ages 18 years and above
2. Patients who had a response (achievement of platelet count >= 50,000/microL) to IVIg/anti-D or CSs that was not sustained and who have documented intolerance, insufficient response or any contra-indication to any appropriate courses of standard of care ITP therapy
3. An average of 2 platelet counts at least 5 days apart of <30,000/microL during the Screening period and no single platelet count >35,000/microL within 14 days prior to the first dose of study drug
- Pediatric patients must additionally be determined to need treatment for ITP as per clinical assessment by the Investigator
4. Adequate hematologic, hepatic, and renal function (absolute neutrophil count >= 1.5 X 10^9/L, AST/ALT <= 1.5 x upper limit of normal [ULN], albumin >= 3 g/dL, total bilirubin <= 1.5 x ULN [unless the patient has documented Gilbert syndrome], glomerular filtration rate >50 [Cockcroft and Gault method])
5. Hemoglobin >9 g/dL within 1 week prior to Study Day 1
6. All contraceptive use by men and women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies
7. Patients must be able to provide written informed consent or informed assent with corresponding informed consent obtained from the patient's guardian and agree to the schedule of assessments

Exclude criteria

Participants are excluded from the study if any of the following criteria apply:
1. Patients with secondary ITP
2. Pregnant or lactating women
3. History (within 5 years of Study Day 1) or current, active malignancy requiring or likely to require chemotherapeutic or surgical treatment during the study, with the exception of non melanoma skin cancer
4. Transfusion with blood, blood products, plasmapheresis, or use of any other rescue medications with intent to increase platelet count within 14 days before Study Day 1
5. Change in CS and/or TPO-RA dose within 14 days prior to Study Day 1 (more than 10% variation from current doses)
6. Immunosuppressant drugs other than CSs within 5 times the elimination half-life of the drug or 14 days of Study Day 1, whichever is longer
7. Treatment with rituximab or splenectomy within the 3 months prior to Study Day 1
- Patients treated with rituximab will have normal B-cell counts prior to enrollment
8. Has received any investigational drug within the 30 days before receiving the first dose of study medication, or at least 5 times elimination half-life of the drug (whichever is longer); patient should not be using an investigational device at the time of dosing
- Patients who previously received treatment with Bruton's Tyrosine Kinase (BTK) inhibitors (except rilzabrutinib) within 30 days before the first dose of study drug are not eligible
- Patients who previously received rilzabrutinib at any time are not eligible
9. History of solid organ transplant
10. Myelodysplastic syndrome
11. Live vaccine within 28 days prior to Study Day 1 or plan to receive one during the study
12. Planned surgery in the time frame of the dosing period

Related Information

• Primary Sponsor: Tanaka Tomoyuki
• Secondary ID(s): NCT04562766