Rituximab plus anti‑CD38 antibody versus rituximab alone for primary immune thrombocytopenia

A Randomized, Open-label Study To Compare The Efficacy And Safety Of Rituximab Combining Anti-CD38 Monoclonal Antibody Versus Rituximab in ITP Patients Who Failed or Relapsed After Glucocorticoid Therapy

This trial will test whether adding an anti‑CD38 antibody (daratumumab) to rituximab helps adults with primary ITP who did not respond to or relapsed after steroid treatment.

Quick facts

• Phase: Phase 2
• Study type: Interventional
• Enrollment: 160 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Institute of Hematology & Blood Diseases Hospital, China (Academic / other)
• Drugs / interventions: rituximab, prednisone, Daratumumab
• Locations: 1 site (Tianjin, Tianjin Municipality)
• Trial ID: NCT07234019 on ClinicalTrials.gov

What this trial studies

This is a randomized, open‑label phase 2 trial comparing rituximab combined with an anti‑CD38 monoclonal antibody (daratumumab) versus rituximab alone in adults with primary immune thrombocytopenia refractory to or relapsed after glucocorticoid therapy. Participants must have had primary ITP for at least three months and sustained platelet counts below 30×10^9/L on repeated testing. The trial will measure platelet responses and safety outcomes to determine whether targeting CD38‑expressing plasma cells improves durability of response. The study is conducted at the Institute of Hematology & Blood Diseases Hospital (Tianjin, China).

Who should consider this trial

Good fit: Adults aged 18 or older with primary ITP for at least three months, platelet counts persistently under 30×10^9/L, and prior failure or relapse after glucocorticoid therapy are the intended participants.

Not a fit: Patients with secondary causes of thrombocytopenia, active uncontrolled infection, pregnancy, or other contraindications to monoclonal antibody therapy may not benefit from or be eligible for this approach.

Why it matters

Potential benefit: If successful, the combination could produce higher or more durable platelet responses and reduce the need for ongoing ITP treatments.

How similar studies have performed: Small case series and reports have shown promising responses using daratumumab for refractory autoimmune cytopenias, but randomized data in ITP are limited and this combination approach is not yet proven.

Eligibility criteria

Inclusion Criteria:

* Age ≥18 years, male or female.
* Before enrollment, the subjects have been clinically diagnosed with primary immune thrombocytopenia for no less than three months according to the American Society of Hematology guidelines 2011 Evidence-Based Practice Guideline (Neunert et al. 2011) or the International Consensus Report for the Investigation and Management of Primary Immune Thrombocytopenia (Provan et al. 2010), as applicable locally.
* Subjects with a platelet count of \<30×10\^9/L within the 48 hours prior to the first dose of the study drug;The platelet count of at least two separate assessments (at least 1 week apart) \<30×10\^9/L during the screening visit.
* Patients have failed glucocorticoid therapy (either due to inefficacy, efficacy could not be maintained, or relapse).
* Previous emergency treatment for ITP (e.g., methylprednisolone, platelet, gamma globulin infusion) must have been completed at least 2 weeks before the first dose.
* Hepatic and renal function (e.g., alanine aminotransferase, aspartate aminotransferase, total bilirubin, serum creatinine) \<1.5 times the upper limit of normal (ULN).
* ECOG performance status score of ≤2.
* Cardiac function: New York Heart Association (NYHA) class ≤2.
* Enrollment of subjects receiving maintenance therapy is permitted, including glucocorticoids (≤0.5 mg/kg of prednisone or equivalent) or TPO receptor agonists, but the concomitant medication must have been stable for a minimum of 4 weeks prior to the initial infusion of the study drug; Azathioprine, danazol, cyclosporine A, tacrolimus, sirolimus, etc. must be stopped at least 4 weeks before the first dose; CD20 monoclonal antibody such as rituximab must have been stopped for more than 6 months; the interval between splenectomy and first administration need to be more than 6 months.
* For fertile female patients, a negative pregnancy test result is required. Fertile female and male patients must use effective contraception separately during the study and for 90 days after the cessation of study drug treatment.
* Subjects comprehensively understand and can adhere to the study protocol requirements and willingly signed the informed consent form.

Exclusion Criteria:

* Uncontrollable primary diseases of important organs, such as malignant tumors, liver failure, heart failure, renal failure and other diseases.
* HIV positive.
* Accompanied by uncontrollable active infection, including hepatitis B, hepatitis C, cytomegalovirus, EB virus and syphilis positive.
* Accompanied by extensive and severe bleeding, such as hemoptysis, upper gastrointestinal hemorrhage, intracranial hemorrhage, etc..
* At present, there are heart diseases, arrhythmias that need treatment or hypertension that researchers judge is poorly controlled.
* Patients with thrombotic diseases such as pulmonary embolism, thrombosis and atherosclerosis.
* Those who have received allogeneic stem cell transplantation or organ transplantation in the past.
* atients with mental disorders who cannot normally obtain informed consent and conduct trials and follow-up.
* Patients whose toxic symptoms caused by pre-trial treatment have not disappeared.
* Other serious diseases that may limit the subject's participation in this test (such as diabetes; Severe cardiac insufficiency; Myocardial obstruction or unstable arrhythmia or unstable angina pectoris in recent 6 months; Gastric ulcer, etc.).
* Patients with septicemia or other irregular severe bleeding.
* Patients taking antiplatelet drugs at the same time.
* Pregnant women, suspected pregnancies (positive pregnancy test for human chorionic gonadotropin in urine at screening) and lactating patients.
* Subjects with a known allergy to medications were used in the trial or excipients.
* Any other conditions unsuitable for participation in this study, as assessed by the investigator.

Where this trial is running

Tianjin, Tianjin Municipality

• Chinese Academy of Medical Science and Blood Disease Hospital — Tianjin, Tianjin Municipality, China (Recruiting)

Study contacts

• Study coordinator: Lei Zhang, MD

Conditions Immune Thrombocytopenia; Treatment