A Phase 2 Open-Label Safety and Efficacy Study of PF-06835375
- Conditions
- Primary immune thrombocytopeniaMedDRA version: 23.0Level: LLTClassification code: 10083843Term: Primary immune thrombocytopenia Class: 10005329Therapeutic area: Diseases [C] - Hemic and Lymphatic Diseases [C15]
- Registration Number
- CTIS2023-509338-21-00
- Lead Sponsor
- Pfizer Inc.
- Brief Summary
Not available
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- Recruiting
- Sex
- All
- Target Recruitment
- 61
1. Participants between the ages of 18 (or the minimum country specific age of consent if >18) and 70 years, inclusive, at Screening. •Refer to Appendix 4 for reproductive criteria for male and female participants., 2. Willing and able to comply with all scheduled visits, treatment plan, laboratory tests, lifestyle considerations and other study procedures., 3. Diagnosis of Primary ITP. ITP must be diagnosed in accordance with established guidelines.12,22,29 • Ongoing ITP (platelet counts <50 x 103/mL) [No severe bleeding within 1 month or during screening]. AND • Persistent ITP (3 to 12 months) or Chronic ITP >12 months. AND • Failed initial therapy or require alternative therapy for ITP, in the opinion of the Investigator., 4. BMI 17.5 to 40 kg/m2, and minimum weight >40 kg (88 lbs)., 5. Capable of giving signed informed consent as described in Appendix 1 which includes compliance with the requirements and restrictions listed in the ICD and in this protocol.
1. Bleeding event according to the WHO grading scale30 =2 occurring =4 weeks prior to screen OR a current bleeding event that, in the opinion of the investigator, requires treatment with standard of care therapy OR require blood or blood products during screening (8.1.2)., 10. Co-existing thrombotic thrombocytopenic purpura, hemolytic uremic syndrome, coagulopathies or other bleeding disorders., 11. History of immune deficiency or current evidence of total IgG or total IgA deficiency., 12. History of allergic or anaphylactic reaction to any components of the study intervention., 13. Have cancer or a history of cancer within 5 years of screening (other than adequately resected cutaneous basal cell, squamous cell carcinoma, or carcinoma in situ of the uterine cervix with no evidence of recurrence within the previous 3 years)., 14. Any psychiatric condition including recent or active suicidal ideation or behavior that meets any of the following criteria: • Suicidal ideation associated with actual intent and a method or plan in the past year: Yes” answers on items 4 or 5 of the C-SSRS (Section 10.12). • Previous history of suicidal behaviors in the past 5 years: Yes” answer (for events that occurred in the past 5 years) to any of the suicidal behavior items of the C-SSRS. • Any lifetime history of serious or recurrent suicidal behavior., 15. Current use of any prohibited concomitant medication(s) or those unwilling/unable to use a permitted concomitant medication(s). Refer to 6.8., 16. Any prior treatment with rituximab (or any other B cell depleting agent) must have been completed 12 months prior to first dose of study drug and CD19 count (>100 cells per microliter) must be normal prior to first dose., 17. Recent high doses corticosteroids (> 20 mg prednisone or equivalent per day). If on corticosteroids, must be on a stable dose for =28 days prior to the first dose (maximum dose up to 20 mg/day prednisone equivalent) and expected to remain on a stable dose throughout the study. See 10.9 for equivalence detail., 18. Treatment with IVIg =28 days prior to the first dose., 19. Treatment with plasmapheresis within 3 months prior to the first dose., 2. Splenectomy within 3 months of randomization or planned during the study duration., 20. Treatment with an anti-Rh D antigen agent (eg, WinRho®) =28 days prior to the first dose., 21. If receiving avotrombopag, eltrombopag, fostamatinib, or romiplostim, the dose must have been stable for =28 days prior to the first dose of study intervention and must be expected to remain stable throughout the study., 22. If receiving adjunct immunosuppressants such as cyclosporine, azathioprine, mycophenolate, or 6-mercaptopurine, the doses must be stable for 2 months prior to Day 1 and anticipated to remain stable throughout the study. Stable dosages should not exceed MMF 3 g/day; AZA 2 mg/kg/day and cyclosporine 5 mg/kg/day. See Section 6.8.1 for details., 23. Treatment with other cytotoxic agents (eg, cyclophosphamide, vincristine) is not allowed within 3 months prior to the first dose., 24. Use of any systemic treatment or herbal supplement that is known to affect platelets (ie, resveratrol)., 25. Previous administration with an investigational drug within 30 days (or as determined by the local requirement) or 5 half-lives preceding the first dose of study intervention used in this study (whichever is longer)., 26. Presence of any of the following laboratory abnormalities at Screening: • B-cell count below
Study & Design
- Study Type
- Interventional clinical trial of medicinal product
- Study Design
- Not specified
- Primary Outcome Measures
Name Time Method Main Objective: To evaluate absolute value of platelet count of treated participants at Week 12 (6 mg cohort) and at Week 16 (18 mg cohort).;Secondary Objective: To evaluate proportion of participants with modified overall response (mOR) at Week 12 (6 mg cohort) and at Week 16 (18 mg cohort), To evaluate proportion of participants with complete response (CR) at Week 12 (6 mg cohort) and at Week 16 (18 mg cohort), To evaluate safety and tolerability of PF 06835375, To evaluate effect of PF-06835375 treatment on platelet count over time, To evaluate the effect of PF-06835375 on depletion of circulating B cells and cTfh cells over time.;Primary end point(s): Log2 (platelet count) at Week 12 (6 mg cohort) and at Week 16 (18 mg cohort)
- Secondary Outcome Measures
Name Time Method Secondary end point(s):Modified overall response (mOR) at Week 12 (6 mg cohort) and at Week 16 (18 mg cohort);Secondary end point(s):Complete response (CR) at Week 12 (6 mg cohort) and at Week 16 (18 mg cohort);Secondary end point(s):Incidence of AEs as characterized by type, frequency, severity, timing, seriousness, and relationship to study intervention, Day 1 through end of study;Secondary end point(s):Log2 (platelet count);Secondary end point(s):Modified response (mOR);Secondary end point(s):Complete response (CR);Secondary end point(s):Absolute values and change of platelet count from baseline;Secondary end point(s):Absolute values and change from baseline of circulating B and cTfh cell counts