Innovent dosed the first patient in the Phase 3 TriadicMM-1 trial of IBI3003, a GPRC5D/BCMA/CD3 trispecific antibody for relapsed or refractory multiple myeloma. Early data showed an 83.3% response rate with manageable safety in heavily pretreated patients.
Written By: Sana Khan, BPharm
Reviewed By: Pharmacally Editorial Team
Innovent Biologics has dosed the first patient in TriadicMM-1 (NCT07623798), a pivotal Phase 3 trial evaluating its investigational trispecific antibody IBI3003 in patients with relapsed or refractory multiple myeloma (R/R MM). The study marks a significant milestone for the program, making IBI3003 the first China-developed GPRC5D/BCMA/CD3 trispecific antibody to enter registrational Phase 3 testing.
The randomized, open-label Phase 3 TriadicMM-1 trial is evaluating IBI3003 against investigator’s choice of pomalidomide, bortezomib, and dexamethasone (PVd) or daratumumab, pomalidomide, and dexamethasone (DPd) in patients with relapsed or refractory multiple myeloma who have received one to four prior lines of therapy. The study’s primary endpoint is progression-free survival (PFS) as assessed by an independent review committee (IRC).
A Dual-Antigen Strategy to Overcome Tumor Escape
IBI3003 is built on Innovent’s proprietary Sanbody® platform and simultaneously targets GPRC5D, BCMA, and CD3. By engaging two myeloma-associated antigens while recruiting T cells through CD3, the therapy is intended to reduce the risk of antigen escape, a known challenge with single-target therapies.
Multiple myeloma remains the second most common hematologic malignancy worldwide. Although proteasome inhibitors, immunomodulatory agents, anti-CD38 antibodies, and newer cellular therapies have improved outcomes, most patients eventually relapse and develop treatment resistance. Effective therapies with novel mechanisms remain a major unmet need, particularly after multiple prior treatment lines.
Early Clinical Data Show Strong Activity
Data presented at the American Society of Hematology (ASH) Annual Meeting in December 2025 provided early evidence of IBI3003’s clinical potential.
Among 24 patients treated at doses of at least 120 μg/kg, the overall response rate (ORR) reached 83.3%. Responses included four stringent complete responses, seven very good partial responses, and nine partial responses.
The therapy also demonstrated activity in difficult-to-treat populations. Patients with extramedullary disease achieved an ORR of 80%, while those previously exposed to BCMA- and/or GPRC5D-targeted therapies achieved an ORR of 77.8%.
Among patients achieving complete response or better, all evaluable patients were minimal residual disease (MRD)-negative based on next-generation sequencing assessment.
Safety findings were consistent with expectations for T-cell-engaging therapies. All cytokine release syndrome events were Grade 1 or 2, and only two Grade 1-2 cases of immune effector cell-associated neurotoxicity syndrome (ICANS) were reported. Most GPRC5D-related adverse events affecting the skin, nails, and oral cavity were mild to moderate, with only two cases of Grade 3 rash.
Clinical Implications
Professor Peng Liu of Zhongshan Hospital Affiliated to Fudan University, the study’s principal investigator, emphasized the need for new therapeutic options as treatment responses often diminish with successive relapses. He noted that TriadicMM-1 could help establish a new treatment standard if the trial confirms the encouraging early findings.
Innovent’s oncology R&D leadership described the Phase 3 initiation as a key step in advancing the company’s trispecific antibody portfolio and broader immunotherapy strategy.
Clinical Path Forward
Beyond China, IBI3003 is being evaluated in an ongoing Phase I/II trial across China, Australia, and the United States (NCT06083207). The therapy also received Fast Track Designation from the U.S. Food and Drug Administration for heavily pretreated R/R MM patients who have previously received a proteasome inhibitor, immunomodulatory drug, and anti-CD38 antibody.
Results from ongoing dose-optimization studies and selection of the recommended Phase 2 dose are expected to be presented at future scientific meetings, while TriadicMM-1 will determine whether IBI3003 can advance toward regulatory approval in China.
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About the Writer
Sana Jamil Khan (LinkedIn) is a B. Pharm graduate with a strong interest in medical writing and scientific communication. Her work focuses on interpreting clinical research, exploring developments in pharmaceutical science, and presenting complex medical information in a clear and accessible manner. She is particularly interested in topics related to human clinical studies, drug safety observations, and emerging therapeutic research.