Safety and clinical efficacy of BCMA CAR-T-cell therapy in multiple myeloma

  • J Hematol Oncol. 2020 Dec 3;13(1):164. doi: 10.1186/s13045-020-01001-1.
Gils Roex  1 Marijke Timmers  2 Kristien Wouters  3 Diana Campillo-Davo  1 Donovan Flumens  1 Wilfried Schroyens  2 Yiwei Chu  4 Zwi N Berneman  2 Eva Lion  1 Feifei Luo  4  5 Sébastien Anguille  6  7
Affiliations
  • 1. Laboratory of Experimental Hematology, Vaccine and Infectious Disease Institute, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.
  • 2. Division of Hematology and Center for Cell Therapy & Regenerative Medicine, Antwerp University Hospital, Edegem, Belgium.
  • 3. Clinical Trial Center, Antwerp University Hospital, Edegem, Belgium.
  • 4. Biotherapy Research Center, Fudan University, Shanghai, China.
  • 5. Department of Digestive Diseases, Huashan Hospital of Fudan University, Shanghai, China.
  • 6. Laboratory of Experimental Hematology, Vaccine and Infectious Disease Institute, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium. [email protected].
  • 7. Division of Hematology and Center for Cell Therapy & Regenerative Medicine, Antwerp University Hospital, Edegem, Belgium. [email protected].
Abstract

Background: B-cell maturation antigen (BCMA)-targeted chimeric antigen receptor (CAR)-T-cell therapy is an emerging treatment option for multiple myeloma. The aim of this systematic review and meta-analysis was to determine its safety and clinical activity and to identify factors influencing these outcomes.

Methods: We performed a database search using the terms "BCMA," "CAR," and "multiple myeloma" for clinical studies published between 01/01/2015 and 01/01/2020. The methodology is further detailed in PROSPERO (CRD42020125332).

Results: Twenty-three different CAR-T-cell products have been used so far in 640 patients. Cytokine release syndrome was observed in 80.3% (69.0-88.2); 10.5% (6.8-16.0) had neurotoxicity. A higher neurotoxicity rate was reported in studies that included more heavily pretreated patients: 19.1% (13.3-26.7; I2 = 45%) versus 2.8% (1.3-6.1; I2 = 0%) (p < 0.0001). The pooled overall response rate was 80.5% (73.5-85.9); complete responses (CR) were observed in 44.8% (35.3-54.6). A pooled CR rate of 71.9% (62.8-79.6; I2 = 0%) was noted in studies using alpaca/llama-based constructs, whereas it was only 18.0% (6.5-41.1; I2 = 67%) in studies that used retroviral vectors for CAR transduction. Median progression-free survival (PFS) was 12.2 (11.4-17.4) months, which compared favorably to the expected PFS of 1.9 (1.5-3.7) months (HR 0.14; p < 0.0001).

Conclusions: Although considerable toxicity was observed, BCMA-targeted CAR-T-cell therapy is highly efficacious even in advanced multiple myeloma. Subgroup analysis confirmed the anticipated inter-study heterogeneity and identified potential factors contributing to safety and efficacy. The results of this meta-analysis may assist the future design of CAR-T-cell studies and lead to optimized BCMA CAR-T-cell products.

Keywords
BCMA; CAR-T; Multiple myeloma.