ATRA for Management of Primary ITP

All-trans Retinoic Acid for Management of Primary Immune Thrombocytopenia : a Randomized, Double-blind, Placebo-controlled Study

A multicenter, randomized, double-blind placebo-controlled study to report the efficacy and safety of all-trans etinoic acid compared to placebo for the treatment of adults with corticosteriod-resistant/relapsed primary immune thrombocytopenia (ITP).

Study Overview

• Status: Not yet recruiting
• Conditions: Immune Thrombocytopenia
• Intervention / Treatment: Drug: all-trans retinoic acid (ATRA); Drug: Placebo

Detailed Description

The investigators are undertaking a parallel-group, multicenter, randomized controlled trial of 192 adults with corticosteriod-resistant/relapsed primary ITP. Patients were randomized to all-trans etinoic acid and placebo group. Platelet count, bleeding, and other symptoms were evaluated before and after treatment. Adverse events are also recorded throughout the study.

• Study Type: Interventional
• Enrollment (Estimated): 192
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Xiaohui Zhang, Prof.; Phone Number: 861088326001; Email: zhangxh@bjmu.edu.cn
• Study Contact Backup: Name: Haixia Fu, Dr.; Phone Number: 861088326002; Email: fuhaixia_210@163.com

Study Locations

• China
  • Beijing, China
    • Peking University Institute of hematology, People's Hospital
    • Contact: Xiaohui Zhang; Phone Number: 861088326001; Email: zhangxh@bjmu.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Primary ITP if aged ⩾18 years;
• With an average of two platelet counts ⩾1 day apart of <30×10^9/L during screening and no single platelet count >35×10^9/L within 2 weeks before study treatment;
• Patients who have previously received at least one first-line standard therapy for ITP (corticosteroid and/or intravenous immunoglobulin) with unsustained efficacy, relapse, intolerance to standard therapy, or insufficient response.

Exclusion Criteria:

• Pregnant or lactating women, and who were possibly pregnant, planning to become pregnant, or who had partners planning to become pregnant;
• With active malignancy or a history of malignant tumor;
• Having experienced severe bacterial, viral, fungal or parasitic infection within the past 4 weeks;
• With a history of symptomatic herpes zoster infection within 12 weeks prior to screening;
• Active or chronic HBV, HCV or HIV infection;
• Evidence of active tuberculosis; or previous evidence of active tuberculosis without appropriate and documented treatment; or household contact with patients with active tuberculosis without appropriate and documented tuberculosis prophylaxis;
• Receipt of live vaccines within the past 12 weeks, or planned live vaccination during the study period;
• Prior ATRA therapy;
• History of solid organ transplant or planned surgery;
• Myelodysplastic syndrome, aplastic anemia or myelofibrosis;
• Patients with other diseases were undergoing treatment with immunosuppressants;
• Clinically significant thromboembolic events within the past 24 weeks, or ongoing anticoagulant treatment, who are deemed ineligible for the study by the investigator;
• History or presence of myocardial infarction, unstable ischemic heart disease, stroke, or NYHA Class IV heart failure;
• History or presence of cardiovascular, respiratory, hepatic, gastrointestinal, endocrine, neurological, neuropsychiatric or any other severe and/or unstable diseases that, in the opinion of the investigator, may pose an unacceptable risk with the investigational product or interfere with the interpretation of study data;
• AST > 2 times the upper limit of normal (ULN), ALT > 2×ULN, TBIL ≥ 1.5×ULN;
• WBC < 2500/µL, neutrophil count < 1200/µL, lymphocyte count < 750/µL, hemoglobin < 9 g/dL;
• eGFR < 50 mL/min/1.73m²;
• Other patients deemed unsuitable for enrollment in this study by the investigator.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ATRA; ATRA 10mg twice daily	Drug: all-trans retinoic acid (ATRA); 10mg twice daily ×24 weeks; Other Names: tretinoin
Placebo Comparator: Placebo; Placebo 10mg twice daily	Drug: Placebo; 10mg twice daily ×24 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Durable platelet response	Platelet count of ⩾50 × 10^9/L or between ⩾30 × 10^9/L and <50 × 10^9/L and at least doubled from baseline on at least four of six scheduled visits between weeks 14 and 24	Up to week 24

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
24-week overall response rate	From enrollment to the end of week 24, the proportion of patients with at least one platelet count of ≥50×10⁹/L or between 30 × 10^9/L and 50 × 10^9/L plus at least doubled from baseline	Up to week 24
12-week overall response rate	From enrollment to the end of week 12, the proportion of patients with at least one platelet count of ≥50×10⁹/L or between 30 × 10^9/L and 50 × 10^9/L plus at least doubled from baseline	Up to week 12
Consecutive Increased Platelet Counts (≥2 Consecutive PLT ≥ 30×10^9/L)	The proportion of participants who achieved platelet counts ≥ 30×10^9/L and at least doubled from baseline at two consecutive visits	Up to week 24
Consecutive Increased Platelet Counts (≥2 Consecutive PLT ≥ 50×10^9/L)	The proportion of patients with two consecutive platelet counts of 50×10⁹/L or more and doubling from the baseline count	Up to week 24
Quality of Life Score	ITP-patient assessment questionnaire (ITP-PAQ) was used to assess the HRQoL before and after treatment.	Up to week 24
Adverse Events	The rate of participants with adverse events	Up to week 28
Complete response rate	The proportion of patients with a platelet count of ≥ 100×10^9/L in absence of bleeding at any time	Up to week 24
Duration of response	Number of weeks with platelet count of ≥50 × 10^9/L or between 30 × 10^9/L and 50 × 10^9/L plus at least doubled from baseline	Up to 24 weeks
Time to response	Time from treatment initiation to first platelet count reaching ≥30x10^9/L and doubling from the baseline count in 0-24 weeks	Up to week 24
Initial response	Platelet count ≥30×10^9/L and at least doubling baseline at day 28	Up to week 4
Peak platelet count	The peak platelet count without rescue treatment	Up to week 24
Bleeding events	Bleeding incidence and severity per WHO bleeding score in 0-12 weeks and 0-24 weeks	0-12 weeks and 0-24 weeks
Rescue treatment	Proportion of patients receiving predefined rescue treatment	Up to week 24
Reduced or discontinued concomitant therapy	Proportion of patients with reduced or discontinued baseline concomitant anti-ITP therapy	Up to week 24

Collaborators and Investigators

• Sponsor: Peking University People's Hospital
• Collaborators: Peking University First Hospital; Beijing Friendship Hospital; Peking University Third Hospital; Beijing Tongren Hospital; Beijing Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): May 30, 2026
• Primary Completion (Estimated): December 30, 2027
• Study Completion (Estimated): December 30, 2028

Study Registration Dates

• First Submitted: May 13, 2026
• First Submitted That Met QC Criteria: May 13, 2026
• First Posted (Actual): May 19, 2026

Study Record Updates

• Last Update Posted (Actual): May 19, 2026
• Last Update Submitted That Met QC Criteria: May 13, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: ATRA; Immune thrombocytopenia;; Corticosteriod resistance resistant/relaped
• Additional Relevant MeSH Terms: Cytopenia; Pathologic Processes; Autoimmune Diseases; Immune System Diseases; Hemorrhage; Skin Manifestations; Hematologic Diseases; Blood Coagulation Disorders; Hemorrhagic Disorders; Blood Platelet Disorders; Thrombotic Microangiopathies; Purpura, Thrombocytopenic; Purpura; Thrombocytopenia; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Hemic and Lymphatic Diseases; Purpura, Thrombocytopenic, Idiopathic; Organic Chemicals; Retinoids; Carotenoids; Polyenes; Alkenes; Hydrocarbons, Acyclic; Hydrocarbons; Cyclohexenes; Cyclohexanes; Cycloparaffins; Hydrocarbons, Alicyclic; Hydrocarbons, Cyclic; Terpenes; Pigments, Biological; Biological Factors; Diterpenes; Vitamin A; Tretinoin
• Other Study ID Numbers: 2025PHD007-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No