SHANGHAI, China, September 23, 2026 — ImmuneOnco Biopharmaceuticals (Shanghai) Inc. ("ImmuneOnco") today announced updated results from the ongoing Phase Ib/IIa clinical study (NCT05771883) evaluating amulirafusp alfa (IMM0306) in combination with lenalidomide for the treatment of relapsed or refractory (R/R) CD20-positive B-cell non-Hodgkin lymphoma (NHL). IMM0306 is a novel, first-in-class myeloid cell engager (MCE) independently developed by ImmuneOnco based on its proprietary "mAb-Trap" technology platform, which simultaneously targets CD47 and CD20. The latest data demonstrate that the combination regimen delivers high response rates, durable progression-free survival benefits, and a favorable safety profile in patients with R/R marginal zone lymphoma (MZL) and R/R follicular lymphoma (FL), offering a highly promising new therapeutic option for patients with R/R indolent B-cell lymphomas. The Phase II clinical study is ongoing.

R/R MZL Cohort: ORR of 92.3%, CRR of 53.8%

Marginal zone lymphoma (MZL) is the most common indolent lymphoma after follicular lymphoma, accounting for approximately 7%–15% of all non-Hodgkin lymphoma cases. Treatment options remain limited following the failure of first-line therapies, leaving patients with R/R MZL with a high unmet medical need.

As of September 20, 2026, the study had enrolled 13 patients with R/R CD20-positive MZL.

The objective response rate (ORR) reached 92.3%

The complete response rate (CRR) reached 53.8%

Compared with the ORR of 57.8% and CRR of 12% reported for approved BTK inhibitors, amulirafusp alfa (IMM0306) in combination with lenalidomide has the potential to provide a more efficacious treatment option for patients with MZL.

R/R FL Cohort: ORR of 88.6%, CR Rate of 70.5%

As of September 20, 2026, data from 44 efficacy-evaluable patients with R/R CD20-positive FL enrolled in the Phase IIa portion showed that the IMM0306 plus lenalidomide regimen achieved a complete response (CR) rate of 70.5% and an ORR of 88.6%.

In cross-trial comparisons with other "immunomodulatory drug plus monoclonal/bispecific antibody" combination regimens in R/R FL, the regimen demonstrated superior performance:

Versus obinutuzumab plus lenalidomide: the CR rate of the IMM0306 combination regimen (70.5%) was significantly higher than the 38.0% reported in historical Phase II data for that combination (N=86), indicating a stronger capacity for tumor clearance;

Versus rituximab plus lenalidomide (the R² regimen): the R² regimen achieved a CR rate of 34.7% in a historical Phase II study (N=147), whereas the IMM0306 combination regimen doubled the CR rate (70.5% vs. 34.7%), with the ORR further improved from 80.3% to 88.6%;

Versus tafasitamab plus the R² regimen: even against this three-drug combination (N=273, data presented at the 2024 ASH meeting), the two-drug IMM0306 combination maintained a higher ORR (88.6% vs. 83.5%) and a clear CR advantage (70.5% vs. 52.0%).

These results indicate that, through its differentiated design featuring higher affinity for CD20 than for CD47, IMM0306 preferentially binds to CD20 on the surface of tumor cells. By sparing normal CD47-expressing cells, this mechanism simultaneously engages macrophage-mediated antibody-dependent cellular phagocytosis (ADCP) and activates the immune system against tumor cells, thereby achieving deeper responses.

Safety: No Cytokine Release Syndrome (CRS)-Related Toxicity Observed

Notably, unlike currently popular bispecific T-cell engager (TCE) therapies, no severe toxicities or neurotoxicity related to cytokine release were observed in this study. The toxicity profile of IMM0306 was primarily characterized by hematologic events that are well known and manageable in clinical practice, greatly reducing the complexity of clinical management while improving treatment adherence and quality of life for patients.

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

"IMM0306 is a cornerstone asset in our CD47 pipeline. Today's data validate the program on multiple dimensions simultaneously: in MZL, an indication with significant unmet medical need, the ORR reached 92.3% and the CRR 53.8%, bringing new hope to patients with relapsed or refractory disease; in follicular lymphoma, an ORR of 88.6% and a CR rate of 70.5% mean that the regimen not only controls the disease but also offers patients a genuine opportunity to achieve a deep, tumor-free state. Most importantly, the very low discontinuation rate, the absence of CRS-related toxicity, and no treatment-related deaths across the entire MZL/FL population establish a 'highly effective and well tolerated' therapeutic window — this is the core strength of the regimen and validates the success of our differentiated innovation strategy. ImmuneOnco will continue to advance the global clinical development of IMM0306, with the aim of bringing benefit to more patients with hematologic malignancies and solid tumors."

Dr. Zhuli Wu, Chief Medical Officer of ImmuneOnco, stated:

"IMM0306 simultaneously binds to CD47 and CD20 on B cells, and through its triple mechanism of action it can clear B cells more thoroughly, thereby achieving superior tumor cell killing. We are delighted to see that the combination of IMM0306 and lenalidomide has yielded excellent ORR and CRR in patients with relapsed or refractory MZL and FL, enabling patients to achieve deeper and more durable responses with a favorable safety profile — findings of significant clinical importance for patients with relapsed or refractory indolent lymphomas who have limited treatment options."