Daiichi Sankyo disclosed an “extraordinary loss” of 149.4 billion yen (about $950 million) and moved to scrap plans for antibody-drug conjugate manufacturing capacity. The loss was linked to overestimating demand for ADCs manufactured for third parties, driving a sizable financial reset and prompting a rethink of capacity assumptions. The decision highlights execution risk in the ADC manufacturing model, where third-party demand forecasts can shift quickly as competitive pipelines and clinical readouts change partner strategies. For the broader biotech and pharma manufacturing ecosystem, the update underscores how downstream capacity commitments can unwind when utilization falls short. The company’s move arrives as ADC supply chains remain central to how biotech sponsors scale clinical programs and commercial launches—making changes to manufacturing plans a practical signal of where market demand is headed.