Oxford BioMedica falls 15% as CAR-T trial pauses hit manufacturing

Oxford BioMedica's shares fell 15% after two of its largest customers paused autoimmune CAR-T programmes on safety concerns, a setback for the contract manufacturer that likely supplies the viral vector for both halted studies. The London-listed cell and gene therapy maker closed at 447p on Tuesday, against a 690p target that Panmure Liberum kept intact.

The scale of the decline looks overdone given the company's already depressed valuation and the breadth of its pipeline, Panmure Liberum said. Autoimmune indications account for only 13% of Oxford BioMedica's 48 programmes as of April 2025, the broker noted, suggesting the near-term revenue impact should fall within the flexibility already built into current guidance.

Novartis halted screening, randomisation and dosing across eight clinical trials of rapcabtagene autoleucel, or rap-cel, on 24 August after three patients died from immune effector cell-associated haemophagocytic syndrome, a rare and potentially life-threatening inflammatory reaction. Bristol Myers Squibb separately paused enrolment in its zola-cel programme out of an "abundance of caution" after detecting transient and reversible inflammatory events, though it reported no deaths. Both therapies use CD19-directed CAR constructs derived from the companies' marketed cancer drugs — Novartis' Kymriah and BMS' Breyanzi — re-engineered for faster manufacturing.

Oxford BioMedica does not disclose programme-level detail, but Panmure Liberum said it was likely the company manufactures viral vector for both paused assets. The two drugmakers are among the leaders in a broad push to redirect CAR-T therapies against autoimmune diseases such as lupus, systemic sclerosis and multiple sclerosis, an approach that early academic data suggests can drive long-lasting remissions. William Blair analyst Sami Corwin flagged that the rapid-production technology behind both candidates "could be driving increased cell expansion and the reported toxicities," though she cautioned other factors may be involved.

What the pauses mean for Oxford BioMedica

The immediate financial hit is limited by the small share of autoimmune work in Oxford BioMedica's portfolio, but the longer-term risk hinges on the regulatory response. Novartis said it is engaged with regulators and reviewing findings across the rap-cel programme, while BMS aims to resume testing "as quickly as possible." Cancer studies of rap-cel continue, and BMS was set to begin a zola-cel trial in systemic sclerosis this month before the pause.

A broader safety review could slow the entire autoimmune CAR-T field, where rivals including Cabaletta Bio and Kyverna Therapeutics are also running trials. Kyverna could submit an approval application in stiff person syndrome by year-end, and Cabaletta has a late-stage study in myositis underway. Any tightening of regulatory scrutiny would ripple through the contract manufacturing chain that Oxford BioMedica sits atop.

Oxford BioMedica reports interim results on 22 September, when investors will get the first disclosed read on how the pauses affect its manufacturing revenue. At 447p, the shares trade well below the 690p target Panmure Liberum maintained, leaving roughly 54% implied upside if the trial halts prove temporary and the broader pipeline carries the valuation.

This article is for informational purposes only and does not constitute investment advice.