Biokin’s world-first bispecific ADC hits milestones, speeding commercialization

Iza-bren was approved for recurrent or metastatic esophageal squamous cell carcinoma, after receiving earlier approval to treat nasopharyngeal carcinoma

Key Takeaways:

• New approvals for Biokin’s Iza-bren highlight the rise of China’s role in developing bispecific ADCs, and their effectiveness in treating a growing range of solid tumors
• The company aims to become a multinational corporation using major-indication “super blockbuster” products, as it prepares to launch Iza-bren overseas by 2029

By Molly Wen

As a sector-wide correction for innovative drug stocks bottoms out, major breakthroughs and commercial rollouts have become the most potent catalysts for reviving investor confidence in individual companies. Since late June, Sichuan Biokin Pharmaceutical Co. Ltd.’s (688506.SH), listed on Shanghai’s STAR market, has voluntarily announced that its investigational drug Izalontamab brengitecan (Iza-bren) has completed first patient dosing in two Phase Three clinical trials for biliary tract cancer and breast cancer.

Over the past month, China’s National Medical Products Administration (NMPA) has also approved two marketing applications for indications of the company’s internally developed EGFR×HER3 bispecific antibody-drug conjugate (ADC), for the treatment of advanced nasopharyngeal carcinoma and recurrent or metastatic esophageal squamous cell carcinoma (ESCC). The latest approval marks the world’s first bispecific ADC for ESCC and carries the potential to redefine the standard of care.

The positive news sparked a major rally for Biokin’s Shanghai-listed stock, which surged by 40% in a month since it made the first announcement. While the stock is listed on China’s domestic A-share market, it is also available to foreign investors through the Shanghai-Hong Kong Stock Connect program.

ADCs, often dubbed “biological missiles,” precisely target cancer via an antibody–linker–payload design and have become a core focus of global drug development. With 2,334 ADCs in pipelines — 75% of those conventional — the crowded single-target space is driving bispecific ADCs as the next-generation approach.

As a first-in-class EGFRxHER3 bispecific ADC, Iza-bren locks onto the epidermal growth factor receptor (EGFR) on one end and the human epidermal growth factor receptor 3 (HER3) on the other. Both receptors drive tumor growth and resistance in cancers such as lung and nasopharyngeal.

The dual EGFR/HER3 blockade using Iza-bren overcomes resistance, exhibits a low rate of discontinuation in only 2.6% in patients, and enables dosing just once every three weeks, relieving the burden on patients.

In the bispecific ADC arena, Biokin boasts a generational lead. Iza-bren is the first bispecific ADC to conclude a Phase Three registrational clinical study and achieve approval, with the closest candidates behind it at just the Phase Two clinical stage. The time gap has given Biokin a clear first-mover advantage.

Iza-bren’s first approved indication is for adults with recurrent or metastatic nasopharyngeal carcinoma (NPC) after failure of at least two chemotherapy lines and PD-1/PD-L1 therapy, addressing a major unmet need in South China and Southeast Asia. It shows better efficacy and survival versus standard chemotherapy and is the preferred regimen in both the “NCCN Guidelines for Nasopharyngeal Cancer: Chinese Edition (2026)” and the “2026 CSCO Guidelines for the Diagnosis and Treatment of Nasopharyngeal Carcinoma.”

Broader commercialization potential

As a first-in-class EGFR×HER3 bispecific ADC developed in China, Iza-bren gained approval to treat ESCC within a month of filing, a notable milestone. The approval expands its use into major solid tumors, launching a multi-tumor strategy and advancing bispecific ADC therapy.

“This approval marks a key step in expanding Iza-bren into major solid tumors and signals the rise of bispecific ADC therapy in high-incidence cancers, advancing China’s position at the forefront of global biopharma innovation,” said Biokin Chairman Zhu Yi.

With broader clinical adoption, Iza-bren is expected to be rapidly incorporated into standard treatment guidelines in China and globally, potentially becoming the new standard second-line therapy for recurrent or metastatic ESCC, offering improved survival prospects for patients with advanced solid tumors.

Iza-bren also shows global commercialization potential for treating a variety of other solid tumors. By June 2026, the drug had kicked off more than 40 pan-tumor clinical trials in the two core markets of China and the U.S., receiving a total of eight breakthrough therapy designations.

Globally, Biokin has launched three pivotal registrational trials. Bristol Myers Squibb (BMY.US), its key co-developer outside China, is positioning Iza-bren as a key oncology asset with a broad development roadmap.

On global commercialization, Biokin Chairman Zhu said the company’s R&D, clinical, and supply-chain strengths are well-established. But commercialization is still developing, with overseas markets largely led by Bristol Myers Squibb under their $8.4 billion Iza-bren partnership. Amid geopolitical cost pressures, Zhu said profitability hinges on “super blockbuster” drugs, scale via multi-product synergies, and in-licensing to build a global pipeline and offset overseas commercialization costs.

Regarding overseas regulatory expectations, Zhu pointed out in an interview with Bamboo Works that top-tier clinical data generated in China can also win endorsement from the U.S. FDA under mutual data recognition principles of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). As for regulatory mandates involving racial disparities, the company just needs to conduct bridging studies to supplement population data and establish the absence of significant clinical divergence, he said. Previously, the company’s second ADC drug, BL-M07D1, leveraged vast amounts of domestic PD-1 combination data to pave the way for a bridging trial in the U.S., validating the viability of such a path.

Biopharma revaluations often hinge on a lead asset moving from the development to commercialization stage. For Biokin, China’s approval of Iza-bren validates such a path and marks the start of its shift toward a multinational model. Investors will now focus on whether its domestic and global commercialization can scale into sustained sales and profits.

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