Micrograph showing DLBCL
Researchers have reported the first known case of central nervous system (CNS) lymphoma responding to chimeric antigen receptor (CAR) T-cell therapy.
The investigational CAR T-cell therapy JCAR017 induced complete remission of brain metastasis in a patient with refractory diffuse large B-cell lymphoma (DLBCL).
When a subcutaneous tumor began to recur 2 months after the patient received JCAR017 and a surgical biopsy was performed, the CAR T cells spontaneously re-expanded and the tumor again went into remission.
While the patient eventually relapsed and died more than a year after receiving JCAR017, the brain tumor never recurred.
“Brain involvement in DLBCL carries a grave prognosis, and the ability to induce a complete and durable response with conventional therapies is rare,” said Jeremy Abramson, MD, of Massachusetts General Hospital in Boston.
“In addition, all available CAR T-cell trials have excluded patients with central nervous system involvement. This result has implications not only for secondary DLBCL like this case but also for primary central nervous system lymphoma, for which treatment options are similarly limited after relapse and few patents are cured.”
Dr Abramson and his colleagues described this case in a letter to NEJM. The patient was involved in a trial of JCAR017, which was sponsored by Juno Therapeutics.
The patient was a 68-year-old woman with germinal center B-cell-like DLBCL with a BCL2 rearrangement and multiple copies of MYC and BCL6.
The patients’ disease was refractory to conventional chemotherapy and an 8/8 HLA-matched stem cell transplant. After she enrolled in a phase 1 trial of JCAR017, the patient was found to have a new lesion in the right temporal lobe of her brain.
One month after the patient received JCAR017—given after lymphodepletion with fludarabine and cyclophosphamide—imaging showed complete remission of the brain lesion.
The subcutaneous lesion that recurred 2 months later disappeared after the biopsy with no further treatment. Blood testing showed an expansion of CAR T cells that coincided with the tumor’s regression.
While re-expansion of CAR T cells has been reported in response to other immunotherapy drugs, this is the first report of such a response to a biopsy.
“Typically, the drugs we use to fight cancer and other diseases wear off over time,” Dr Abramson said. “This spontaneous re-expansion after biopsy highlights this therapy as something entirely different, a ‘living drug’ that can re-expand and proliferate in response to biologic stimuli.”
