# Novartis CAR T cell therapy trial suspensions

> Live situation record from CLSTR: https://clstr.news/situations/novartis-car-t-cell-therapy-trial-suspensions
> Updated: 2026-09-07T05:45:49.000Z. Sources: 35. Developments: 2.

Novartis has halted eight clinical trials involving an experimental CAR T cell therapy following three deaths. The fatalities were linked to immune effector cell-associated hemophagocytic syndrome (IEC-HS), a condition where the immune system attacks the body’s own organs.

The suspension affects studies targeting various autoimmune and neurological disorders, such as systemic lupus erythematosus, rheumatoid arthritis, and multiple sclerosis. Novartis is conducting a review with independent safety boards to determine if methods exist to detect these side effects earlier. While these specific trials are paused, the company confirmed that its oncology programs using the same therapy for leukemia and lymphoma remain unaffected.

## Claims

- The drug del-desiran failed to reach its primary endpoint in a study for muscle disease. (disputed by 6 sources)
- The success of the del-desiran trial is required to justify the $12 billion Avidity acquisition. (disputed by 2 sources)
- Novartis stock price dropped by approximately 10 percent following the clinical trial results. (corroborated by 5 sources)
- The drug pelacarsen did not reduce the risk of heart attacks or strokes in clinical trials. (corroborated by 4 sources)
- Jefferies analysts maintained a 'Hold' rating for Novartis with a price target of 110 CHF. (corroborated by 3 sources)

## Timeline

### 2026-09-07: Novartis shares plunge following dual clinical trial failures

Novartis shares fell up to 10% after two major clinical trial failures: the cholesterol drug pelacarsen failed to reduce cardiovascular events, and the muscle disease treatment del-desiran missed its primary 목표

31 sources. https://clstr.news/cluster/novartis-receives-hold-rating-from-jefferies-company

### 2026-09-01: Novartis halts eight CAR T cell therapy trials following three deaths

Novartis has paused eight clinical trials for an experimental CAR T cell therapy after three deaths caused by severe immune reactions in patients with autoimmune and neurological diseases.

3 sources. https://clstr.news/cluster/novartis-halts-eight-car-t-cell-therapy-trials-following-three-deaths

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Cite as: Novartis CAR T cell therapy trial suspensions. CLSTR, https://clstr.news/situations/novartis-car-t-cell-therapy-trial-suspensions