TheTechno Optimist.

ESO-T01AstraZeneca—ESO-T01 Phase 1 for multiple myeloma published in Nature Medicine; all patients developed Grade 3+ cytokine release syndrome

AstraZeneca

Biopharmaceutical, oncology, cell therapy, in vivo CAR-T

GB$246B est. market cap~90,000 staffest. 1999astrazeneca.com (opens astrazeneca.com)Checked 10 Oct

The brief

Analyst view
  • AstraZeneca is a major pharma company formed in 1999 from Swedish Astra AB and British Zeneca. Headquarters in Cambridge, UK.
  • Acquired EsoBiotec in May 2025 for up to $1B to develop in vivo CAR-T therapies with infused viral vectors.
  • ESO-T01 for multiple myeloma showed early activity but all Phase 1 patients developed severe cytokine release syndrome.

Technical approach

As reported
In vivo CAR-T

CAR-T made inside the patient

Lentiviral vector infects T cells with CAR gene in bloodstream, avoiding leukapheresis and ex vivo manufacturing.

Nanobody-directed vector

Immune-shielded delivery

ESO-T01 uses a nanobody-directed lentiviral vector designed to reduce immune activation, though clinical results showed persistent inflammatory responses.

Off-the-shelf potential

No cell manufacturing

In vivo CAR-T eliminates leukapheresis, cell engineering, and the 2–4 week manufacturing wait if the safety challenges are solved.

Primer