Shanghai, China, March 17, 2026 – ImmuneOnco Biopharmaceuticals (Shanghai) Inc. (“ImmuneOnco”; HKEX Stock Code: 01541.HK) today announced that the Phase II clinical trial of its independently developed novel agent, Amouravfop alfa (IMM0306), for the treatment of Primary Membranous Nephropathy (PMN), has officially received approval from the National Medical Products Administration (NMPA). This marks another significant milestone in ImmuneOnco’s strategic layout within autoimmune nephrology, representing a substantive step forward in bringing this innovative therapy to the field of kidney disease treatment.

Multi-Point Breakthroughs in Autoimmune Pipeline Demonstrating Platform Innovation Strength

The approval of the Phase II trial for Amouravfop alfa in Primary Membranous Nephropathy (PMN), coupled with the recent Investigational New Drug (IND) approval for the subcutaneous formulation of Amouravfop alfa (IMM0306S), represents the latest achievement in ImmuneOnco’s intensive deployment in autoimmune diseases. These developments underscore the Company’s “multi-point breakthrough” strategy in its autoimmune pipeline.

Amouravfop alfa has achieved critical progress across multiple high-value autoimmune indications, building a rich and deep product portfolio:

• IgG4-Related Disease (IgG4-RD): IND approved.

• Systemic Lupus Erythematosus (SLE):

  • Intravenous (IV) formulation: Phase Ib/II clinical trials ongoing.

  • Subcutaneous (SC) formulation (IMM0306S): IND approved.

• Neuromyelitis Optica Spectrum Disorder (NMOSD): Phase Ib/III clinical trials ongoing.

• Lupus Nephritis (LN): Phase II clinical trial approved.

• Primary Sjögren’s Syndrome (pSS): IND application accepted.

• Primary Membranous Nephropathy (PMN): Phase II clinical trial approved (current approval).

This series of breakthroughs—spanning from early-stage research to late-stage clinical development, and from intravenous to subcutaneous administration—fully validates the robust extensibility and commercial potential of ImmuneOnco’s proprietary “mAb-Trap” technology platform. It further demonstrates the Company’s unwavering commitment to addressing major unmet medical needs.

Significant Unmet Needs in the Treatment of Primary Membranous Nephropathy

Primary Membranous Nephropathy is one of the most common pathological types of nephrotic syndrome in adults, characterized by immune complex deposition beneath the epithelial cells of the glomerular basement membrane, accompanied by diffuse thickening of the basement membrane. Approximately 30%-40% of patients may progress to End-Stage Renal Disease (ESRD). Furthermore, about 30% of patients exhibit inadequate response to existing therapies or experience relapse after discontinuation, while access to some novel agents remains limited. There is an urgent need for innovative therapies that offer higher efficacy and lower relapse rates. The approval of this Phase II trial for IMM0306 will accelerate the in-depth development of new drugs in this field, offering new hope for these patients.

The potential of IMM0306 in the autoimmune domain has been strongly supported by preliminary clinical data. In Phase Ib/II clinical studies for Systemic Lupus Erythematosus (SLE), IMM0306 demonstrated superior efficacy and safety profiles. Relevant data have been presented at top-tier international academic conferences, such as the American College of Rheumatology (ACR) annual meeting, garnering high attention from global experts. These findings provide a solid scientific basis for expanding IMM0306 into other autoimmune indications, including membranous nephropathy.

Multi-Indication Layout with Parallel Advancement in Hematology

Based on positive Phase I/II clinical data, the Phase III clinical trial protocol for IMM0306 in combination with lenalidomide for the treatment of Relapsed/Refractory Follicular Lymphoma (R/R FL) was approved by the Center for Drug Evaluation (CDE) in November 2025, officially entering the registration-enabling clinical stage.

Data presented at the 67th American Society of Hematology (ASH) Annual Meeting revealed that this combination regimen achieved an Objective Response Rate (ORR) of 91.2% and a Complete Response (CR) rate of 67.6% in patients who had failed at least one prior line of anti-CD20 monoclonal antibody-containing therapy. The regimen demonstrated a generally manageable safety profile with no risk of cytokine release syndrome (CRS). This outcome offers a highly promising immunotherapy strategy for patients with relapsed/refractory follicular lymphoma.

Dr. Tian Wenzhi, Founder, Chairman, CEO, and CSO of ImmuneOnco, stated:

“The approval of the Phase II clinical trial for IMM0306 in Primary Membranous Nephropathy marks another key breakthrough in our nephrology portfolio, following our progress in Lupus Nephritis. Patients with membranous nephropathy have long faced a dilemma of limited treatment options. We believe that the innovative mechanism of IMM0306 will bring new hope to these patients. We will actively advance the clinical research to strive for providing superior treatment solutions to patients as soon as possible.”

Ms. Wu Zhuli, Chief Medical Officer of ImmuneOnco, commented:

“The pathogenesis of Primary Membranous Nephropathy (PMN) is closely linked to abnormal B-cell activation and autoantibody production. As an innovative bispecific fusion protein, IMM0306 simultaneously targets CD47 and CD20, enabling the efficient clearance of pathogenic B-cells and plasmablasts. This ‘dual-strike’ mechanism holds the promise of overcoming the efficacy bottlenecks of existing single-target drugs. Based on the rapid onset of action and deep remission data observed in our SLE studies, we are confident that the upcoming Phase II clinical trial in PMN will further validate the immense potential of IMM0306 in reducing proteinuria, inducing clinical remission, and helping patients reduce steroid dependence, thereby providing an efficient and safe therapeutic solution for this refractory kidney disease.”