Plain language summary of the CARTITUDE-1 study of ciltacabtagene autoleucel for the treatment of people with relapsed or refractory multiple myeloma

What is this summary about? This is a summary of a clinical study called CARTITUDE-1. This study tested the anti-cancer chimeric antigen receptor-T cell (CAR-T) therapy ciltacabtagene autoleucel, abbreviated as cilta-cel, in people with multiple myeloma, a cancer that affects a specific type of blood cell called plasma cells. The participants in this study had relapsed or refractory disease, which means that their cancer did not improve or returned after 3 or more previous anti-cancer treatments. How was the study in this summary conducted? Ninety-seven participants went through the treatment process, which included collecting participants' own T cells (a type of immune cell), genetically modifying those T cells to recognize a certain protein found on myeloma cancer cells, pretreating with chemotherapy to prepare the participant's immune system to accept the modified T cells (cilta-cel), and finally injecting cilta-cel. What were the results of this study? Ninety-eight percent of participants showed decreases in indicators of cancer after treatment with cilta-cel. Seventy percent of participants were still alive approximately 28 months after treatment, and 55% of participants were still living without their cancer getting worse. The most common side effects were low blood cell levels, infections, cytokine release syndrome (a potentially serious side effect caused by overactivation of the immune system), and side effects that involved the nervous system (called neurotoxicities). Some participants experienced late-onset symptoms of neurotoxicity like the signs and symptoms of parkinsonism, meaning that they affected people's movement. Improvements in recognition of factors that increase the risk of these late-onset neurotoxicities and strategies to help avoid them has reduced their occurrence, although long-term monitoring for side effects is still an important part of treatment. What do the results of the study mean? Overall, almost all participants treated with cilta-cel had long-term reductions in signs of myeloma, and the majority of participants were alive and had no detectable signs of cancer over 2 years after being injected with cilta-cel. Clinical Trial Registration: NCT03548207 (1b/2 CARTITUDE-1 study) NCT05201781 (Long-term Follow-up Study for Participants Previously Treated With Ciltacabtagene Autoleucel) </sec.