ELIANA: the global trial that made tisagenlecleucel the first approved CAR-T therapy for children and young adults with relapsed ALL
Across 25 centres, 81% of children and young adults with relapsed or refractory ALL went into remission after a single tisagenlecleucel infusion, and half were still event-free a year later.
ELIANA was a single-arm, multicentre phase 2 trial of tisagenlecleucel in patients aged 3-21 with CD19-positive relapsed or refractory B-cell ALL. Of 92 enrolled, 75 received an infusion; the rest could not because of manufacturing failure, death or adverse events. The overall remission rate within three months was 81%, all MRD-negative; event-free survival was 73% at six months and 50% at 12 months, with overall survival 90% and 76%. Cytokine release syndrome occurred in 77% (grade 3-4 in about 46%) and neurological events in 40%. The trial supported FDA approval in August 2017, the first gene therapy and first CAR-T approved in the United States, and demonstrated that a centrally manufactured autologous cell product could be delivered across continents.
- 92 enrolled, 75 infused; 25 centres in 11 countries; median age 11.
- Overall remission rate within 3 months 81%; all remissions MRD-negative.
- Event-free survival 73% at 6 months and 50% at 12 months; overall survival 90% and 76%.
- CRS 77% (grade 3-4 in about 46%; 48% needed tocilizumab; 47% intensive care); neurological events 40%.
- Manufacturing failed in 7 of 92 and 17 enrolled patients were never infused, highlighting the vein-to-vein problem.
ELIANA turned CAR-T from a single-centre experiment into a licensed product and created the regulatory and logistical template every later cell therapy has followed. For children with refractory leukaemia it offers a chance of durable remission without transplant. The trial also exposed the gaps: manufacturing failures, patients dying while waiting, and roughly half relapsing within a few years.
- Single-arm; no randomised comparator and outcomes reported on infused rather than enrolled patients in most analyses.
- Severe CRS rates were high by later standards, before prophylactic strategies.
- Long-term relapse, often CD19-negative, affects about half; some patients still proceed to transplant.
- List price around 475,000 US dollars at launch raised affordability and access questions.
The UCART19 report was the first clinical evidence that a universal, pre-manufactured CAR-T made from a donor can work, avoiding the weeks of autologous manufacturing and the problem of patients whose own T cells are too damaged. It set the template for later allogeneic programmes (including cemacabtagene autoleucel in the ALPHA studies) and for in vivo CAR generation. Short persistence and the need for deep lymphodepletion remain the central weaknesses.
This paper is the proof-of-concept for a living drug: a single infusion of a patient's own engineered T cells could eradicate leukaemia that had survived chemotherapy, transplant and antibody therapy. It defined cytokine release syndrome and its antidote, tocilizumab, and revealed antigen-loss relapse. It led directly to the first approved gene-modified cell therapy three years later.