AstraZeneca and Daiichi Sankyo presented new data showing Enhertu (trastuzumab deruxtecan) produces substantive benefits when moved into earlier-stage breast cancer settings, signaling a tactical shift for antibody-drug conjugates (ADCs) at ESMO. Trial readouts reported higher response and cure potential in neoadjuvant/early disease cohorts, expanding the drug’s addressable patient population. AstraZeneca framed the results as validation for accelerating ADCs beyond late-line indications. At the same meeting AstraZeneca executives argued their in-house ADC platform — built on proprietary linkers and topoisomerase I payloads — yields competitive differentiation and sustained tolerability across dose ranges. The company showed first-in-human activity for AZD5335, an FRα-targeted ADC in platinum-resistant ovarian cancer, with double-digit response rates and manageable neutropenia as the primary grade ≥3 toxicity at higher doses (AstraZeneca phase 1/2a data presented Oct. 18). These presentations underscore ADC developers’ dual push: broaden indications for proven agents while advancing next-gen, internally sourced platforms.