A Study of GR1803 Injection Versus Daratumumab, Pomalidomide, and Dexamethasone (DPd) in Participants With Relapsed or Refractory Multiple Myeloma

NCT07452198 | Recruiting Phase 3 DMC

• 1 other identifier: GR1803-004
• Study Type: interventional
• Target: 358
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to compare the efficacy of GR1803 Injection with daratumumab in combination with pomalidomide and dexamethasone (DPd).

Conditions

Multiple Myeloma

Outcome Measures

Primary Outcomes (1)

• Progression Free Survival (PFS)

  Up to 5 years

Secondary Outcomes (12)

• Overall Survival (OS)

  Up to 5 years

• Progression Free Survival on Next-line Therapy (PFS2)

  Up to 5 years

• Overall Response (Partial Response [PR] or Better)

  Up to 5 years

• Complete Response (CR) or Better

  Up to 5 years

• Duration of Response

  Up to 5 years

Study Arms (2)

Arm A: GR1803 Injection

EXPERIMENTAL

Drug: GR1803 injection

Arm B: DPd

ACTIVE COMPARATOR

Drug: Daratumumab; Drug: Pomalidomide; Drug: Dexamethasone

Interventions

GR1803 injection DRUG

Participants received intravenous GR1803 injection at a dose of 180 ug per kilogram, which had been preceded by step-up doses of 10 and 30 ug per kilogram.

Arm A: GR1803 Injection

Daratumumab DRUG

Participants received subcutaneous Daratumumab at a dose of 1800 mg.

Arm B: DPd

Pomalidomide DRUG

Participants received Pomalidomide at a dose of 4 mg on days 1 to 21 of each cycle (28 days).

Arm B: DPd

Dexamethasone DRUG

Participants received once-weekly dexamethasone at a dose of 40 mg (≤75 years) or 20 mg (\>75 years).

Arm B: DPd

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Have an eastern cooperative oncology group (ECOG) performance status score of 0, 1, or 2 at screening and baseline.
• Diagnosed as multiple myeloma according to the diagnostic criteria of the International Myeloma Working Group (IMWG) diagnostic criteria.
• Received 1 to 3 prior line(s) of antimyeloma therapy including a proteasome inhibitor (PI) and lenalidomide; a. participants who have received only 1 line of prior line of antimyeloma therapy must be lenalidomide refractory. Stable disease or progression on or within 60 days of the last dose of lenalidomide given as maintenance will meet this criterion.
• Documented evidence of progressive or stable disease based on investigator's determination of response by IMWG criteria on or after their last regimen.
• Measurable disease at screening and baseline as defined by any of the following: 1) serum M-protein level greater than or equal to (\>=) 5 gram per liter (g/L); or 2) urine M-protein level \>=200 milligrams (mg)/24 hours; or 3) serum immunoglobulin free light chain \>=100 mg/L and abnormal serum immunoglobulin kappa lambda free light chain ratio.
• Have clinical laboratory values within the specified range.
• Have an understanding of and comply with the clinical trial protocol requirements, voluntarily participate in the clinical trial, and sign the informed consent form.

You may not qualify if:

• Plasma cell leukemia, Waldenström's macroglobulinemia, POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes), or amyloidosis (including primary and secondary).
• History or clinical signs of central nervous system involvement or meningeal involvement of multiple myeloma .
• Received any prior B cell maturation antigen (BCMA)-directed therapy.
• Has disease that is considered refractory or intolerant to an anti-cluster of differentiation 38 (CD38) targeted therapy or Pomalidomide.
• Prior antitumor therapy, within 21 days (PI 、IMiDs or radiotherapy within 14 days, clinical trial vaccine within 28 days, Gene modified adoptive cell therapy within 3 months, allogeneic stem cell transplantation within 6 months, autologous stem cell transplantation within 12 weeks) prior to first dose of study drug.
• Received a cumulative dose of corticosteroids equivalent to \>=140 mg of prednisone within 14 days prior to first dose of study drug.
• Grade \>= 2 peripheral neuropathy at screening.
• History of Guillain Barre Syndrome (GBS) or variant GBS.
• The following medical conditions: active infecion, human immunodeficiency virus (HIV) infection, hepatitis B or C infection, Syphilis infection, thromboembolic events or cerebrovascular events less than or equal to (\<=) 6 m, seizure attacks less than or equal to (\<=) 6 m.
• Active malignancies other than relapsed/refractory multiple myeloma within 3 years prior to screening.
• Active autoimmune disease or history of autoimmune disease.
• Received a live, attenuated vaccine within 4 weeks before first dose of study drug.
• Have major surgery within 2 weeks before first dose of study drug.
• Contraindications or life-threatening allergies, hypersensitivity, or intolerance to any study drug or its excipients.
• Pregnant, lactating female.

Sponsors & Collaborators

• Genrix (Shanghai) Biopharmaceutical Co., Ltd.: lead

Study Sites (1)

Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences

Tianjin, China

RECRUITING

MeSH Terms

Conditions

Multiple Myeloma

Interventions

daratumumab; pomalidomide; Dexamethasone

Condition Hierarchy (Ancestors)

Neoplasms, Plasma Cell; Neoplasms by Histologic Type; Neoplasms; Hemostatic Disorders; Vascular Diseases; Cardiovascular Diseases; Paraproteinemias; Blood Protein Disorders; Hematologic Diseases; Hemic and Lymphatic Diseases; Hemorrhagic Disorders; Lymphoproliferative Disorders; Immunoproliferative Disorders; Immune System Diseases

Intervention Hierarchy (Ancestors)

Pregnadienetriols; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Steroids, Fluorinated

Central Study Contacts

Gang An

CONTACT

13502181109; angang@ihcams.ac.cn

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 28, 2026
• First Posted: March 5, 2026
• Study Start: March 9, 2026
• Primary Completion (Estimated): March 1, 2029
• Study Completion (Estimated): March 1, 2030
• Last Updated: March 25, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)