Oxford Biomedica shares fell more than 24% after the British cell and gene therapy manufacturer cut its 2026 revenue forecast, citing a six-month delay to operational readiness at its Durham, North Carolina site and weaker near-term demand from clients. The company now expects 2026 sales of £180 million to £200 million, down from previous guidance of £220 million to £240 million, and said changes in client ordering behaviour included delayed programme timelines and altered procurement pathways from a large client. The stock dropped to its lowest level in nearly a year and was on course for its worst day since June 2013 as of 0741 GMT. Oxford Biomedica also said its 2026 core profit margin, excluding one-off costs, should be in the mid-single-digit percentage range, while maintaining its medium-term goals of 25-30% revenue growth and about £500 million in revenue by 2030.