Market Analysis Report for Zhixiang Jintai's GR1803 Bispecific Antibody

On January 8, 2026, Zhixiang Jintai (Stock Code: 688443.SH) announced that the conditional marketing application for its self-developed BCMA×CD3 bispecific antibody drug GR1803 Injection (generic name: Velinotamig) has been accepted by the National Medical Products Administration (NMPA) [1][2]. The indicated population for this application is:

[1][2].

Item	Details
Drug Name	GR1803 Injection (Velinotamig)
Target Combination	BCMA × CD3
Registration Classification	Class 1 Therapeutic Biological Product
Developer	Zhixiang Jintai (Chongqing Zhixiang Jintai Biopharmaceuticals Co., Ltd.)
Drug Type	Bispecific Antibody (T-cell Engager)

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GR1803 adopts a

, whose structure is highly similar to that of normal monoclonal antibodies. This design has the following advantages:

• Optimized Manufacturing Process
  : Facilitates process development and reduces production costs
• Reduced Immunogenicity
  : Reduces the risk of immune reactions caused by structural differences
• Enhanced Safety
  : Similar in structure to natural antibodies, with better in vivo tolerance [1][2]

GR1803 adopts an

strategy, which is its core technical advantage:

Target	Affinity (Kd)	Relative Multiple
BCMA	10⁻¹⁰ M	100x higher
CD3	10⁻⁸ M	Baseline

This design’s core logic:

1. High-Efficiency Tumor Targeting
   : High-affinity binding to BCMA ensures precise recognition of myeloma cells
2. Mild T-cell Activation
   : Low-affinity binding to CD3 reduces non-specific T-cell activation
3. Reduced Toxicity
   : Effectively reduces adverse reactions such as cytokine release syndrome (CRS) [1][2]

GR1803 functions through a

:

┌─────────────────┐     ┌─────────────────┐     ┌─────────────────┐
│  BCMA+Tumor Cells│ ←── │  GR1803 Bispecific  │ ──→ │  CD3+T Cells   │
│  (Multiple Myeloma) │     │  (BCMA×CD3)    │     │  (Immune Effector Cells) │
└─────────────────┘     └─────────────────┘     └─────────────────┘
                              ↓
                    ┌─────────────────┐
                    │  Form Immune Synapse │
                    │  Activate T Cells │
                    │  Release Cytokines │
                    └─────────────────┘
                              ↓
                    ┌─────────────────┐
                    │  Tumor Cell Apoptosis │
                    │  Kill Tumor Tissue │
                    └─────────────────┘

---

Based on Phase I study data presented at the November 2025 American Society of Hematology (ASH) Annual Meeting [1]:

:

• As of July 1, 2025, a total of 60 patients were enrolled
• 48 patients received the 180μg/kg dose (Recommended Phase 2 Dose, RP2D)

:

Efficacy Endpoint	Rate	Number of Patients
Objective Response Rate (ORR)	89.5%	51/57
≥Very Good Partial Response (≥VGPR)	-	-
≥Complete Response (≥CR)	-	-
Minimal Residual Disease Negative (MRD-)	-	-

:

Efficacy Endpoint	Rate	Number of Patients
Objective Response Rate (ORR)	87.5%	42/48
≥Very Good Partial Response (≥VGPR)	70.8%	34/48
≥Complete Response (≥CR)	37.5%	18/48
MRD Negative Rate	54.2%	26/48

Drug	Company	ORR	≥VGPR	≥CR	MRD-	Dose
GR1803	Zhixiang Jintai	89.5%	70.8%	37.5%	54.2%	180μg/kg
Teclistamab	Johnson & Johnson	63%	55%	26%	26%	1.5mg/kg
Elranatamab	Pfizer	61%	44%	27%	28%	76mg
Linvoseltamab	Pfizer	71%	51%	30%	31%	200mg

[1][3]:

• ORR is approximately 20-30 percentage points higher than competitors
• Leading deep response rates (≥VGPR/CR)
• MRD negative rate is nearly twice that of Teclistamab

---

As of now, the global BCMA×CD3 bispecific antibody market presents a pattern of

:

Drug	Brand Name	Company	FDA Approval Date	EMA Approval Date	Status in China
Teclistamab	TECVAYLI®	Johnson & Johnson	October 2022	August 2022	Conditional Approval in 2023
Elranatamab	ELREXFIO®	Pfizer	August 2023	2023	Conditional Approval in 2024
GR1803	Velinotamig	Zhixiang Jintai	-	-	Filed in 2026

As the

, Johnson & Johnson’s Teclistamab enjoys first-mover advantage:

:

• On January 6, 2026, Johnson & Johnson submitted an application to the EMA for an indication expansion of
  teclistamab in combination with daratumumab SC
  [4]
• Indication expanded from
  fifth-line therapy to second-line therapy
• Phase III MajesTEC-3 study shows the combination regimen significantly improves patient outcomes

:

Teclistamab (BCMA×CD3) + Daratumumab (CD38)
         ↓
  Dual Targeting: BCMA + CD38
         ↓
  Synergistic Effect: Earlier Activation of Immune System
         ↓
  Clinical Benefit: Applicable for Second-Line Therapy

Pfizer’s Elranatamab received accelerated approval from the FDA in August 2023, making it the

[3]:

:

• Subcutaneous Administration
  : More convenient than Johnson & Johnson’s intravenous administration
• Fixed Dose
  : Fixed dose of 76mg, no need for weight-based adjustment
• Better Compliance
  : Outpatient treatment model

:

• Linvoseltamab (follow-up BCMA×CD3 pipeline)
• Exploration of combination therapies

---

Based on existing clinical data, GR1803 has significant advantages in the following aspects:

1. Higher Response Rate
   : ORR of 89.5% vs competitors’ 60-70%
2. Deeper Remissions
   : ≥CR rate reaches 37.5%, significantly higher than competitors
3. Higher MRD Negative Rate
   : 54.2%, indicating potential curative potential

Safety Indicator	GR1803 Design	Potential Clinical Significance
Affinity Ratio	BCMA:CD3 = 100:1	Reduces excessive T-cell activation
Asymmetric Design	Similar structure to natural antibodies	Reduces immunogenicity
Common Light Chain	Reduces mispairing risk	Improves product homogeneity

In June 2025, Zhixiang Jintai entered into an overseas licensing collaboration with

(NASDAQ: CGEM) [5]:

Collaboration Term	Details
Upfront Payment	$20 million
Milestone Payments	Up to $692 million
Royalties	Up to mid-teens percentage
Licensed Territory	Global rights excluding Greater China
Retained Rights	Independent development and commercialization in Greater China

:

• Total Transaction Value: $712 million
• Validates the international value of GR1803
• Accelerates overseas clinical development with Cullinan’s support
• Zhixiang Jintai retains full rights in the Chinese market

---

Multiple Myeloma (MM) is the

[2]:

:

• High-risk Population: Elderly patients over 60 years old
• Common Symptoms: Hypercalcemia, renal impairment, anemia, bone disease
• Incidence Trend: Overall increasing trend in recent years
• Driving Factor: Deepening aging population

:

• Onset age is 5-10 years younger than in Europe and the US
• Higher proportion of relapsed or refractory patients
• Large unmet treatment needs

Indicator	Data
Global Total MM Patients	Approximately 450,000-500,000
Chinese MM Patients	Approximately 60,000-100,000
Proportion of Relapsed/Refractory Patients	Approximately 40-50%
Treatment Line for BCMA×CD3 Agents	Third-line and beyond

:

1. Growing Patient Population
   : Aging population drives growth in new cases
2. Increased Treatment Penetration
   : Improved accessibility of bispecific antibody drugs
3. Expansion of Combination Therapies
   : Advancement from later-line to earlier-line therapy
4. Domestic Substitution in China
   : High prices of imported drugs

---

Challenge Type	Details
First-Mover Advantage	Johnson & Johnson/Pfizer have established brand and channel advantages
Combination Therapies	Teclistamab+Daratumumab advancing to earlier-line therapy
Price Competition	Imported drugs may trigger price wars
CAR-T Competition	Competition with BCMA CAR-T (e.g., Abecma)

Risk Type	Details
Conditional Approval	Required to complete confirmatory clinical studies
Safety Risks	Immune-related toxicities such as CRS
Production Capacity Challenges	High barriers to bispecific antibody drug production
Internationalization Risks	Uncertainties in the collaboration with Cullinan

Risk Type	Details
Medical Insurance Negotiations	Pricing and medical insurance access for innovative drugs
Competitor Approvals	Progress of other domestic BCMA×CD3 bispecific antibodies
Indication Expansion	Difficulty in advancing from later-line to earlier-line therapy

---

2026 Q1  ──→  Domestic Conditional Approval and Launch
     │
2026 Q2-Q3 ──→  Commercial Team Establishment and Channel Deployment
     │
2026 Q4 ──→  Preparation for Medical Insurance Negotiations
     │
2027 ──→  Completion of Confirmatory Clinical Studies
     │
2028 ──→  Full Approval + Indication Expansion

:

1. Accelerate commercial preparation after conditional approval
2. Establish a hematology sales team and DTP pharmacy channels
3. Launch patient assistance programs to improve accessibility

:

1. Complete confirmatory clinical studies
2. Advance medical insurance negotiations to achieve in-hospital volume growth
3. Expand combination therapy research (in combination with proteasome inhibitors and immunomodulatory agents)

:

1. Advance to earlier-line therapy (from third-line to second-line)
2. Explore new indications such as autoimmune diseases
3. Global layout (self-operation in Greater China + collaboration in Europe and the US)

---

Dimension	Core Viewpoint
Product Strength	ORR of 89.5% significantly leads competitors, with optimized safety design
Time Window	The third domestic BCMA×CD3 bispecific antibody, still with differentiation potential
Internationalization	$712 million licensing collaboration validates its value
Market Space	Growing MM patient population with strong demand for later-line therapy
Catalysts	Conditional approval + commercialization + medical insurance access

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[1] Sina Finance - “ORR Reaches 89.5%! Zhixiang Jintai’s BCMA/CD3 Bispecific Antibody Filed for Marketing” (https://finance.sina.com.cn/stock/relnews/cn/2026-01-08/doc-inhfqyhi5239845.shtml)
[2] Gelonghui/Sina Finance - “Zhixiang Jintai (688443.SH): Conditional Marketing Application for GR1803 Injection Accepted” (https://finance.sina.com.cn/stock/bxjj/2026-01-08/doc-inhfqtyt1350442.shtml)
[3] Pharmcube/Emedcube - “Bispecific/Multispecific Antibodies Enter the ‘TCE Era’! Panoramic View of 20+ Global Pipelines” (https://www.emedclub.com/information/view/qOWPCPbV72MBFEcoRp5Jm)
[4] J&J Media Center - “Novel immunotherapy combination regimen” (https://www.jnj.com/media-center/press-releases/johnson-johnson-submits-application-to-the-european-medicines-agency-for-tecvayli-teclistamab-in-combination-with-darzalex-daratumumab-subcutaneous-formulation-for-patients-with-relapsed-refractory-multiple-myeloma)
[5] Fangda Partners - “Fangda Assists Zhixiang Jintai in Securing Overseas Licensing Collaboration with Cullinan Therapeutics for BCMA×CD3 Bispecific Antibody” (https://www.fangdalaw.com/content/details34_8983.html)

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: This report is compiled and analyzed based on public information and does not constitute investment advice. The R&D and commercialization processes of drugs involve uncertainties, please note the risks when making investment decisions.