Data from a large French registry on a multicenter experience with chimeric antigen receptor T-cell (CAR T) therapy for aggressive lymphoma suggests that the favorable outcomes seen in clinical trials can be replicated in the real world.
Among 481 patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) treated with either of two commercially available CAR T products – tisagenlecleucel (Kymriah) or axicabtagene ciloleucel (Yescarta) – the duration of responses, progression-free survival (PFS), and overall survival (OS) rates at 6 months mirror those seen in clinical trials, reported Steven LeGouill, MD, PhD, from the University of Nantes (France), on behalf of colleagues in the DESCAR-T (Dispositive d’Evaluation et de Suivi des CAR-T) registry.
“CAR T has now become a standard of care in a lot of French centers, with more than 640 patients treated with CAR T in less than 2 years. The DESCAR-T real-life experience mimics the experience that had been previously by other real-life registries but also in clinical trials. We didn’t see new emerging toxicity signals in real life,” he said in an oral abstract session during the European Hematology Association annual congress (Abstract S216).
“I am convinced that a population registry about CAR T–treated patients is needed,” commented Pieter Sonneveld, MD, from Erasmus Medical Center in Rotterdam, the Netherlands, who was not involved in the study.
“Selection criteria for CAR T trials have been incredibly restrictive, and academic trials have not gained ground yet. It is important to collect and analyze more data, include non-trial patients and analyze long-term follow-up in order to determine the real effects of this innovative treatment in lymphoma and other diseases,” he said.
Dr. Sonneveld, EHA past president, was the moderator a briefing where Dr. LeGouill presented the DESCAR-T study findings.
Natalie Sophia Grover, MD, a leukemia and lymphoma specialist at the University of North Carolina at Chapel Hill, noted in an interview that “there have been several publications recently that have shown that these promising outcomes for these really refractory, high-risk patients with diffuse large B-cell lymphoma seem to be similar with what we’ve seen in trials, which is definitely exciting.”
She noted that the median time from CAR T order to treatment in the study, 50 days, was longer than in her experience.
“Generally, from collection to treatment is less than a month. Looking at that, I would have expected more patients not to make it CAR T, but nearly 90% of patients who had collections got treatment, which is pretty good. Those patients that didn’t make it to treatment had really poor outcomes,” she said.
Dr. Grover was not involved in the study.
More data, s’il vous plait
The DESCAR-T registry was created in response to a request from French health authorities for data beyond that provided in the EBMT patient registry. The health authorities asked for characterization of the CAR T–eligible population in an intention to treat, 15-year follow-up of both CAR T recipients and candidates who were not treated for whatever reasons, and a full accounting of previous lines of therapy.
Dr. LeGouill presented the first analysis of data from the registry involving 19 enrolling site and 647 patients with DLBCL for whom CAR T cells were ordered from January 2018 to March 2021.
Of the 647 candidates, 10 did not have CAR T ordered for reasons that included patient deaths or disease progression, infection, and patient refusal. An additional 30 patients either had leukapheresis performed or pending, and 607 had CAR T ordered.
Of the 607 patients, 53 did not receive CAR T infusions because of disease progression, death before product administration, manufacturing or leukapheresis failures, uncontrolled infections, patient choice, or progression of other malignancies.
That left 550 patients (85%) who received a CAR T product, either tisagenlecleucel (200 patients) or axicabtagene ciloleucel (350 patients).
Among all patients, the median age at CAR T order was 63 for patients who received tisagenlecleucel, and 65 for patients receiving axicabtagene ciloleucel. Patients 65 and older comprised 44% and 51% of the population, respectively.
Patients treated with each CAR T product had a median of three prior lines of therapy.
Manageable toxicities
Toxicities within 10 days of CAR T infusion included 418 cases among 515 patients (81.2%) of cytokine release syndrome, with most being grade 1 or 2 in severity; 44 patients had grade 3 or 4 CRS.
Any-grade neurotoxicity was seen in 184 patients (35.7%), primarily grade 1 or 2 in severity; 50 patients had grade 3 or greater neurotoxicity.
Of 427 patients with at least one CAR T–specific toxicity within 10 days, 139 (32.8%) required ICU admission, 325 (76,1%) were treated for CAR T–specific toxicities, 278 (65.1%) received tocilizumab, 13 (3%) received siltuximab, and 176 (41.2%) received corticosteroids.
Favorable outcomes
Overall response rates, at 1, 3, and 6 months post infusions were 70.6%, 56.3%, and 60%, respectively, with the majority of response at each time point being complete responses (CR).
The 6-month overall survival (OS) rate among all patients who were treated was 83.7%, compared with 5.5% for patients who did not receive CAR T infusions.
Progression-free survival (PFS) at 6 months was 44.5%, and 57.7% of patients had an ongoing response at the same time point.
Among patients who received bridging therapy between leukapheresis and CAR T infusion, the 6-month PFS was 58.4% for patients with either a CR, partial response, or stable disease, compared with 63.3% for patients who did not receive bridging therapy, and 29.8% for those with disease progression.
The respective 6 months OS rates were 87.4%, 82.3%, and 65.5%.
The results showed that patients who do not have at least stable disease at the time of CAR T infusion are at risk for early relapse, but approximately 30% of these patients still had long-term disease control, Dr. LeGouill said.
He acknowledged that longer follow-up will be need to see whether the plateaus in the PFS and OS curves the investigators observed can be maintained over time. Questions that still need to be answered include the impact of bridging therapy or disease status at the start of treatment on outcomes, and how to improve CAR T efficacy based on individual patient characteristics.
The registry will be extended to include data on patients treated with CAR T for mantle cell lymphoma and multiple myeloma, investigators announced.
The study is supported by participating centers and Gilead/Kite and Novartis. Dr. LeGouill disclosed advisory board activity and honoraria from the companies and others. Dr. Grover disclosed advisory board participating for Kite and others. Dr. Sonneveld has disclosed research grants and honoraria from several companies, not including Kite or Novartis.