China’s CDE Accepts IND Application for Boan Biotech’s BA1203 (A Masked Anti-PD-1/IL-2 Fusion Protein)

Boan Biotech announced today that the Center for Drug Evaluation (CDE) of China’s National Medical Products Administration (NMPA) has accepted the Investigational New Drug (IND) application for BA1203, an antibody-cytokine prodrug targeting PD-1 and IL-2 pathways. The company developed BA1203 as a next-generation immuno-oncology (IO) therapy intended to treat multiple solid tumors. To the knowledge of the company, BA1203 is poised to become the first masked PD-1/IL-2 antibody-cytokine prodrug retaining α-subunit binding activity to enter clinical trials in China.

Next-gen IO strategy: high-affinity PD-1 antibody + masked IL-2

IO therapies, led by PD-1/PD-L1 inhibitors, have become a cornerstone treatment for malignancies. However, a significant proportion of patients still experience primary non-response, recurrence, or resistance. Previous meta-analyses have shown that PD-1/PD-L1 inhibitor monotherapy yields an overall objective response rate (ORR) of approximately 20%¹, with response rates varying significantly across tumor types and PD-L1 expression levels. These findings highlight the significant unmet clinical need with current immunotherapies.

IL-2 is a critical cytokine that drives T-cell proliferation and functional rejuvenation. However, traditional IL-2 therapies face severe limitations due to a narrow therapeutic window, non-selective peripheral immune cell activation, and systemic toxicity risks. Consequently, achieving targeted delivery and selective activation of IL-2 within the tumor microenvironment (TME) represents a pivotal frontier for next-generation IO therapeutics.

BA1203 leverages the dual mechanism of action of a PD-1 antibody and an IL-2 cytokine, aiming to simultaneously achieve immune checkpoint blockade and localized immune activation within the TME. Through a masked design, the IL-2 prodrug selectively activates within the TME to amplify local anti-tumor immunity while minimizing cytokine activity in peripheral tissues to mitigate systemic toxicity risks. Concurrently, the molecule features a high-affinity, bivalent PD-1 targeting architecture, which enhances pathway blockade and enables precise delivery of IL-2 to PD-1-positive tumor-infiltrating T cells. In addition, BA1203 features a symmetric molecular structure, which improves molecular stability and the controllability of manufacturing process.

Unique strengths validated by preclinical data, with Best-in-Class potential

Preclinical studies show that BA1203 exhibits a differentiated profile in terms of PD-1 binding, immune pathway blockade, and immune activation within the TME. Notably, BA1203 demonstrated superior anti-tumor activity that significantly outperformed existing PD-1/PD-L1 antibodies across multiple tumor models where such checkpoint inhibitors were ineffective or exhibited limited activity. In tumor-bearing mouse models, BA1203 demonstrated superior efficacy compared to the competitor in the same class, while exhibiting a more favorable safety profile driven by tumor-dependent activation. Crucially, while enhancing localized intratumoral immune activation, BA1203 maintains low peripheral toxicity; studies involving cynomolgus monkeys demonstrate its favorable safety and tolerability profile.

Jiang Hua, Chairlady and Chief Executive Officer at Boan Biotech, said:“BA1203 represents our key strategic initiative in developing next-generation IO therapies. Engineered with a symmetric molecular structure, it features high-affinity, bivalent PD-1 targeting coupled with a masked IL-2. We expect such architecture to deliver a superior efficacy and safety profile. Moving forward, we will accelerate BA1203’s clinical development while further exploring its therapeutic potential both as a monotherapy and in combination regimens.”