Engineered T-Cell Trial Halted After Participant Dies

(dimitrisvetsikas1969, Pixabay)

23 November 2016. A clinical trial testing treatments that modify immune system cells to fight leukemia in adults was stopped after one of the patients died from inflammation in the brain. Juno Therapeutics Inc. in Seattle, the company developing the treatments and conducting the trial, says a second participant also developed cerebral edema, a life-threatening condition, and is not expected to recover.

The intermediate-stage clinical trial is testing Juno’s therapy code-named JCAR015 as a treatment for B cell acute lymphoblastic leukemia is a cancer of blood and bone marrow that progresses quickly, making an overabundance of immature lymphocytes, a type of white blood cell. It is the most common type of cancer among children, although it can also affect adults.

JCAR015 harnesses the cancer-fighting ability of a patient’s own T-cells, white blood cells in the immune system, engineered with a gene adding molecules known as chimeric antigen receptors to their DNA. Without these added weapons, cancerous cells evade the immune system, allowing tumors to grow unchecked. The chimeric antigen receptors added to T-cells, called CAR-Ts, are designed in this case to attack cancer cells identified with specific CD19 proteins. These CD19 molecules act as indicators of weakened B-cells in the immune system found with blood-related cancers. The modified T-cells are then infused back into the patient.

As reported in Science & Enterprise, Food and Drug Administration halted this same trial in July 2016 when two participants died after receiving the chemotherapy drug fludarabine as a pre-treatment to remove their original T-cells. Those patients, and a third individual, also developed cerebral edema and died. Juno later replaced fludarabine with the drug cyclophosphamide, and was allowed to continue the trial.

The company in this case stopped the trial itself and notified FDA. Juno says it is working with FDA and its own monitors to consider its next steps. The company adds that its other clinical trials and CAR-T products are continuing.

Until this study, Juno reported a string of favorable results in its early-stage trials, including those testing JCAR015. One of those trials reported in June 2016 with B-cell acute lymphoblastic leukemia patients showed high rates of response and remission, where all signs of leukemia disappear. However, the trial also showed high rates of adverse effects, including severe cytokine release syndrome that occurs when enzymes are emitted from cells targeted by treatments, which can cause flu-like symptoms such as fevers, nausea, and muscle pain, as well as neurological symptoms including hallucinations and delirium.

Read more:

• Clinic Opens for Engineered T-Cell Cancer Therapies
• Trial Shows Engineered T-Cells Can Stop Lymphoma
• Engineered T-Cells Get Leukemia Response
• Engineered T-Cells Get High Leukemia Remission in Trial
• Juno Acquires Biotech, Licenses Cell Sequencing Tech

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