CAR T-cell therapy in relapsed/refractory diffuse large B-cell lymphoma

Abstract

Lay abstract CAR-T therapy is a treatment option for patients with diffuse large B-cell lymphoma that has not responded to at least two other kinds of treatments. CAR-T therapies are manufactured from a patient's white blood cells, modified to attack lymphoma cells. A CAR-T therapy takes time to manufacture after these cells are collected. CAR-T therapies can result in the reduction or disappearance of lymphoma tumors and can increase the chances of survival, but also cause serious side effects for a few patients. One of these is cytokine release syndrome (CRS), in which high levels of inflammation throughout the body may cause fever, heart problems or difficulty breathing. Another is the development of temporary but serious neurological problems such as confusion, seizures and memory problems. To understand how important physicians consider certain features of CAR-T therapies to be when deciding whether to recommend them, we asked physicians to choose between two treatment options resembling CAR-T therapies in a series of questions, with the CAR-T features varying in each question. Their answers indicated whether disappearance of tumors, a patient's chances of survival after 1 and 2 years of treatment, manufacturing time, or the risk of CRS or neurological problems was the most important factor. Physicians most wanted to reduce manufacturing time from 113 to 16 days, but also were willing to accept a >20% increase in risk of severe CRS and a 15% increase in risk of severe neurological events to increase a patient's chance of survival from 40 to 55% at 2 years.

Aims: We evaluated physicians' willingness to trade-off benefits, risks and time to infusion for CAR T-cell therapy for relapsed or refractory diffuse large B-cell lymphoma. Materials & methods: In a discrete-choice experiment survey, 150 US oncologists/hematologists chose between two hypothetical CAR T-cell treatments defined by six attributes. Results: Decreasing time to infusion from 113 to 16 days yielded the greatest change in preference weight (1.91). Physicians were willing to accept a >20% increase in risk of severe cytokine release syndrome and 15% increase in risk of severe neurological events in exchange for an increase in the probability of overall survival at 24 months from 40 to 55%. Conclusion: Physicians value reducing time to infusion and will accept incremental increases in serious adverse event risks to gain survival improvements.