BeOne Medicines Ltd.

# Investment Summary: Disitamab Vedotin (BeOne Medicines) This Phase II trial demonstrates that disitamab vedotin combined with the PD-L1 inhibitor tislelizumab and chemotherapy (S-1) achieves clinically meaningful efficacy as first-line treatment for HER2+ advanced gastric/gastroesophageal junction cancer, a significant unmet need in Asian populations. The triple-agent regimen's safety and efficacy profile positions it as a competitive alternative to current standards of care (trastuzumab-based regimens), potentially expanding BeOne's addressable market in gastric cancer. However, investors should monitor Phase III data and regulatory pathways to assess whether superiority claims over existing trastuzumab combinations can be established, as this will determine commercial viability and uptake likelihood.

# Investment Summary: BeOne Medicines (BEIGF) - HARMONi-6 Trial **Clinical Context:** The HARMONi-6 trial compared ivonescimab (a CTLA-4/PD-L1 bispecific antibody) plus chemotherapy against tislelizumab (PD-L1 monotherapy) plus chemotherapy in advanced squamous non-small cell lung cancer (sqNSCLC), a subset representing approximately 25-30% of NSCLC cases. **Investor Implications:** The clinical outcome of this head-to-head comparison will determine whether ivonescimab's dual-mechanism approach offers meaningful survival or response rate advantages to justify premium positioning in a competitive immunotherapy space. Positive efficacy data with manageable tolerability could support market differentiation and pricing power in sqNSCLC, while non

# BeOne Medicines Investment Summary **Clinical Finding:** Zanidatamab combined with chemotherapy demonstrated survival improvements in advanced HER2-positive gastroesophageal adenocarcinoma (GEA), with additional benefit observed when combined with tislelizumab (PD-L1 inhibitor). **Investor Implications:** This first-line efficacy data strengthens zanidatamab's commercial positioning in a previously difficult-to-treat indication, potentially expanding its total addressable market beyond earlier-stage disease and establishing a multi-agent combination regimen. The triplet therapy option positions BeOne for premium pricing and multiple competitive advantages, though clinical adoption will depend on tolerability profiles and cost-benefit analysis against existing standards of care in this indication.

# Investment Summary: BeOne Medicines - Tislelizumab ESCC Trial **Clinical Finding:** The EC-CRT-002 trial demonstrated that tislelizumab (an anti-PD-L1 checkpoint inhibitor) combined with induction chemotherapy and concurrent chemoradiotherapy improved efficacy outcomes in locally advanced esophageal squamous cell carcinoma (ESCC), a disease with limited treatment options and significant unmet medical need in Asian markets. **Commercial Implications:** This positive Phase II data supports advancement toward registration in ESCC, potentially establishing tislelizumab in a new indication with meaningful market opportunity, particularly in China and other high-incidence regions where ESCC represents a major cancer burden. However, investors should monitor upcoming Phase III readouts and regulatory timelines, as the competitive immunotherapy landscape in solid tumors remains crowded with established checkpoint inhibitors. **Key Risk:**

# Investment Summary: BeOne Medicines (BEIGF) **Clinical Finding:** This case report documents a patient with Bing-Neel syndrome (CNS lymphoplasmacytic lymphoma) who progressed on ibrutinib but responded to zanubrutinib, a second-generation Bruton tyrosine kinase (BTK) inhibitor, suggesting potential efficacy in ibrutinib-resistant disease. **Investor Implications:** The data supports a clinical rationale for zanubrutinib in BTK inhibitor-resistant populations, which could expand the addressable market beyond first-line use and strengthen competitive positioning against ibrutinib. However, this represents a single case report rather than controlled evidence; meaningful commercial impact would require validation in prospective trials demonstrating consistent efficacy in resistant Bing-Neel syndrome—a rare indication with limited commercial scale—and potential label expansion.