On December 14, 2025, ImmuneOnco Biopharmaceuticals (Shanghai) Inc. ("ImmuneOnco", HKEX stock code: 01541.HK) successfully convened the interim investigator meeting for the "Phase Ib/II Clinical Study of Amulirafusp Alfa (IMM0306) Injection in Active Systemic Lupus Erythematosus (SLE)" in Beijing.

This meeting primarily focused on summarizing and discussing the encouraging clinical data from earlier-stage research, reaching consensus on efficacy evaluation, biomarker analysis, and corticosteroid application protocols for the next phase of work.

Summary of Phase Ib Clinical Efficacy and Safety of Amulirafusp Alfa (IMM0306) in Active Systemic Lupus Erythematosus (Based on ACR 2025 Data):

In terms of efficacy, the 24-week SRI-4 response rate was excellent: 71.4% (5/7) in the 0.8 mg/kg group and 80% (4/5) in the 1.2 mg/kg group. Patients achieved complete resolution of arthritis, vasculitis, and alopecia, with significant improvements in key biomarkers including anti-dsDNA antibodies, 24-hour urine protein, and complement C3/C4. Following deep B-cell depletion, 5 patients exhibited orderly B-cell reconstitution between weeks 12-24 (2 cases in the 0.8 mg/kg group, 3 cases in the 1.2 mg/kg group), characterized predominantly by naïve B-cells, which is conducive to long-term immune balance.

Regarding safety, among 19 subjects, 73.7% reported TRAEs (Treatment-Related Adverse Events), most of which were mild to moderate in severity; only 2 cases experienced Grade 3 or higher TRAEs (both thrombocytopenia, which self-resolved within 4-5 days). No DLT (Dose-Limiting Toxicity), CRS (Cytokine Release Syndrome), or significant infection events occurred. Immunoglobulin levels remained normal, and no patients required dose adjustment or died due to TRAEs, demonstrating a favorable overall safety and tolerability profile.

This study is led by Professor Zhan-guo Li, a leading expert in rheumatology and immunology in China from Peking University People's Hospital, bringing together investigators and industry experts from multiple top-tier research centers nationwide to discuss the clinical characteristics and development strategy of this dual-target candidate drug. The atmosphere was vibrant with a strong academic ambiance.

Researchers and Industry Experts Gather Together

The interim investigator meeting officially opened on the morning of December 14, with Professor Zhan-guo Li from Peking University People's Hospital serving as the principal investigator and chairing the discussion sessions. Dr. Wenzhi Tian, Founder and Chairman of ImmuneOnco and Founder of ImmuneCare, and Dr. Qian Zheng, Co-founder and Vice President of ImmuneCare, delivered opening and closing remarks respectively. Ms. Zhuli Wu, Chief Medical Officer of ImmuneOnco, as well as core investigators from multiple research centers nationwide, sponsor medical and project teams, and CRO representatives attended the meeting. All participants demonstrated exceptional professionalism and collaborative spirit, providing a solid foundation for the meeting's successful conclusion.

In his address, Professor Li noted that significant unmet clinical needs remain in SLE treatment. As an innovative drug targeting both CD47 and CD20, Amulirafusp Alfa (IMM0306)'s unique mechanism of B-cell depletion and immune remodeling is highly promising. He emphasized the importance of high-quality completion of the Phase Ib/II clinical trial and called on all centers to work together to advance the project smoothly, hoping to bring new treatment options to patients as soon as possible.

Subsequently, Dr. Wenzhi Tian, as the sponsor representative, addressed the meeting. As a deep player in the CD47 target field and the developer of Amulirafusp Alfa (IMM0306), Dr. Tian reviewed the study journey since the first subject was enrolled in October 2024, highlighting the scientific value of the CD47xCD20 dual-target mechanism in SLE treatment and expressing gratitude to the research teams from all centers for their professionalism in subject screening, efficacy evaluation, and quality control. Dr. Tian noted that Amulirafusp Alfa (IMM0306)'s demonstrated ability to achieve deep B-cell depletion in lymphoma studies provides a solid theoretical foundation for this SLE research, while the significant clinical efficacy and B-cell immune reconstitution characteristics shown in the preliminary Phase Ib data further confirm this molecule's tremendous potential in the autoimmune disease field.

The meeting then progressed to the core discussion segment, where attending experts conducted detailed and thorough deliberations on Phase Ib preliminary efficacy data, safety profiles, and Phase II development strategies. The discussion atmosphere was vigorous, with experts actively speaking up, engaging in in-depth exchanges on key scientific issues and reaching important consensus.

During the experience-sharing and discussion session, Professor Li chaired an in-depth exploration of key quality control points. Experts focused their exchange on the "process quality control" system, reaching consensus on implementation details of the three-tier quality control system comprising routine CRA monitoring, project manager risk management, and independent QC verification. Addressing the unique challenges of SLE clinical trials, experts shared practical experience on core issues affecting data quality, including 24-hour urine collection protocols, corticosteroid tapering compliance management, and scale assessment consistency, and unanimously agreed to strengthen real-time communication and collaboration between central laboratories and investigator teams.

Additionally, the meeting conducted a special discussion on subject compliance management strategies, including measures such as full-process CRC follow-up to avoid missed tests, advanced planning of blood collection windows, standardized prevention and management of infusion reaction protocols, and refined concomitant medication education to ensure data integrity at key efficacy evaluation timepoints (12, 24, and 52 weeks).

All participants also engaged in in-depth discussion on the innovative finding of B-cell reconstitution. Data showed that subjects experiencing B-cell reconstitution were predominantly characterized by naïve B-cells, and all achieved SRI-4 response. Experts agreed that this "immune remodeling" phenomenon warrants further exploration of its clinical significance in Phase II studies.

Future Development Plan

ImmuneOnco plans to rapidly advance Amulirafusp Alfa (IMM0306) from Phase Ib to Phase II in the SLE indication and submit an IND application for clinical development of a subcutaneous formulation. Simultaneously, the company will expand development of Amulirafusp Alfa (IMM0306) across multiple autoimmune disease indications. These strategic plans received high recognition and support from the research experts at this meeting. The successful convening of this investigator meeting marks Amulirafusp Alfa (IMM0306)'s official entry into a new stage of clinical development.

This meeting not only comprehensively summarized Phase Ib study progress but also consolidated collective wisdom through in-depth exchanges, providing a clear action plan for subsequent research implementation. The consensus and collaborative mechanisms established during the meeting will significantly enhance research execution efficiency and data quality, injecting strong momentum into the exploration of innovative SLE therapies. The company sincerely thanks all investigators and partners for their outstanding contributions and will continue to work hand-in-hand with all parties to advance this clinical study with a scientific and pragmatic attitude, striving to convert this innovative therapy into tangible patient benefits as soon as possible and bring positive changes to the global SLE treatment landscape.