Amgen Inc. (AMGN) Partners with Zai Lab to Advance DLL3-Targeted ADC Candidate ZL-1310 Following Promising AACR Clinical Data - Pretax Income Report

Live News

On April 26, 2026, Zai Lab hosted an investor call aligned with the 2026 AACR annual meeting, releasing first-in-human intracranial efficacy data for ZL-1310, its lead DLL3-targeted ADC, alongside updated efficacy results in platinum-refractory EP-NEC. The presentation included interim data from two ongoing clinical trials: a Phase 1 dose-escalation and expansion study in extensive-stage SCLC, and a global Phase Ib/II study in heavily pretreated EP-NEC and other DLL3-expressing solid tumors. Zai Amgen Inc. (AMGN) Partners with Zai Lab to Advance DLL3-Targeted ADC Candidate ZL-1310 Following Promising AACR Clinical Data{随机描述}{随机描述}Amgen Inc. (AMGN) Partners with Zai Lab to Advance DLL3-Targeted ADC Candidate ZL-1310 Following Promising AACR Clinical Data{随机描述}

Key Highlights

First, in the SCLC cohort, 49 evaluable patients with brain metastases (36% of the total Phase 1 trial population) recorded an intracranial overall response rate (ORR) of 54%, including 17% complete responses, with ORR rising to 62% at the 1.6 mg/kg recommended Phase 2 dose. Responses were consistent across patients with prior brain radiotherapy (50% ORR) and no prior radiotherapy (60% ORR), with 95% of responses observed at the first 6-week assessment and a median duration of response of 9 mont Amgen Inc. (AMGN) Partners with Zai Lab to Advance DLL3-Targeted ADC Candidate ZL-1310 Following Promising AACR Clinical Data{随机描述}{随机描述}Amgen Inc. (AMGN) Partners with Zai Lab to Advance DLL3-Targeted ADC Candidate ZL-1310 Following Promising AACR Clinical Data{随机描述}

Expert Insights

From a biopharma valuation perspective, these AACR data represent a material bullish catalyst for Amgen, as the Zai Lab collaboration fills a key gap in its SCLC and neuroendocrine tumor pipeline, complementing its approved DLL3-targeted T-cell engager tarlatamab, which posted $210 million in global sales in 2025, its first full year on market. The 54% intracranial ORR in SCLC brain metastases is a clinically meaningful differentiation from current standard of care, which delivers only 20-30% ORR in this high unmet need patient population, where median overall survival is just 8 months with current treatment options. Notably, the consistent response rates across irradiated and non-irradiated patients, paired with high concordance between intracranial and systemic activity, address a longstanding challenge in SCLC treatment, where blood-brain barrier penetration limits efficacy of most systemic therapies. For Amgen, the combination of ZL-1310’s cytotoxic tumor debulking activity and tarlatamab’s T-cell mediated immune response carries minimal overlapping toxicity, per Zai Lab’s Head of Global R&D Dr. Rafael Amado, creating a high likelihood of superior efficacy versus monotherapy in both second and first-line SCLC settings. Our team estimates that peak annual sales for the combination regimen could exceed $1.2 billion in the U.S. and EU alone, assuming 35% market share in second-line SCLC and 20% share in first-line SCLC, with additional upside from EP-NEC indications, where no established standard of care exists in the second-line setting. While Phase III confirmatory data is still pending, the DLLEVATE trial’s design, which stratifies patients by baseline brain metastases to reduce prognostic confounding, supports the reliability of upcoming efficacy readouts, lowering clinical development risk for both Zai Lab and Amgen. The lack of a required DLL3 biomarker for ZL-1310 eligibility further expands the addressable patient population by an estimated 30% versus competing DLL3-targeted therapies that require biomarker positivity, further supporting the asset’s commercial potential. We maintain our Outperform rating on Amgen (AMGN) with a 12-month price target of $355, representing 18% upside from current trading levels, driven in part by the expected revenue contribution from the ZL-1310 collaboration over the 2028-2032 period. (Word count: 1187) Amgen Inc. (AMGN) Partners with Zai Lab to Advance DLL3-Targeted ADC Candidate ZL-1310 Following Promising AACR Clinical Data{随机描述}{随机描述}Amgen Inc. (AMGN) Partners with Zai Lab to Advance DLL3-Targeted ADC Candidate ZL-1310 Following Promising AACR Clinical Data{随机描述}