CD19/CD20 Bispecific Chimeric Antigen Receptor (CAR) in Naive/Memory T Cells for the Treatment of Relapsed or Refractory Non-Hodgkin Lymphoma

To address antigen escape and loss of T-cell functionality, we report a phase I clinical trial (NCT04007029) evaluating autologous naive and memory T (TN/MEM) cells engineered to express a bispecific anti-CD19/CD20 chimeric antigen receptor (CAR; CART19/20) for patients with relapsed/refractory non-Hodgkin lymphoma (NHL), with safety as the primary endpoint. Ten patients were treated with 36 × 106 to 165 × 106 CART19/20 cells. No patient experienced neurotoxicity of any grade or over grade 1 cytokine release syndrome. One case of dose-limiting toxicity (persistent cytopenia) was observed. Nine of 10 patients achieved objective response [90% overall response rate (ORR)], with seven achieving complete remission [70% complete responses (CR) rate]. One patient relapsed after 18 months in CR but returned to CR after receiving a second dose of CART19/20 cells. Median progression-free survival was 18 months and median overall survival was not reached with a 17-month median follow-up. In conclusion, CART19/20 TN/MEM cells are safe and effective in patients with relapsed/refractory NHL, with durable responses achieved at low dosage levels.

SIGNIFICANCE

Autologous CD19/CD20 bispecific CAR-T cell therapy generated from TN/MEM cells for patients with NHL is safe (no neurotoxicity, maximum grade 1 cytokine release syndrome) and demonstrates strong efficacy (90% ORR, 70% CR rate) in a first-in-human, phase I dose-escalation trial. This article is highlighted in the In This Issue feature, p. 517.

CD19/CD20 bispecific chimeric antigen receptor (CAR) in naïve/memory T cells for the treatment of relapsed or refractory non-Hodgkin lymphoma

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Background: Although chimeric antigen receptor (CAR)-T cells produce impressive outcomes in B-cell malignancies, a substantial fraction of patients with relapsed/refractory B-cell leukemia and lymphoma treated with anti-CD19 CAR-T cell therapy (CART19) either do not respond to treatment or relapse, with poor CAR-T cell persistence or CD19 antigen escape being two key factors that limit durability of response. In order to address these factors, we initiated a clinical trial with naïve/memory T (TN/MEM) cells engineered to express bispecific anti-CD19/CD20 CARs (CART19/20) (NCT04007029). Methods: This trial is a Phase 1, first-in-human, dose-escalation trial enrolling patients with relapsed or refractory follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL), mantle-cell lymphoma (MCL) and chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Following lymphodepletion chemotherapy with fludarabine and cyclophosphamide, patients received CART19/20 cell doses ranging from 50 x 106 to 200 x 106 CAR-positive cells. The primary endpoint was to evaluate the safety of CART19/20 as measured by adverse events and dose limiting toxicities. Secondary endpoints were efficacy as assessed by disease response, progression-free survival (PFS), overall survival (OS), and CAR transgene persistence. Results: As of February 7, 2022, dose-escalation has been completed with 9 patients enrolled and 8 patients infused (3 FL, 4 DLBCL including 2 transformed follicular and 1 primary mediastinal B cell, and 1 MCL). with CART19/20 cells on this study. The median age at the time of CART19/20 infusion was 59 and median prior lines of therapy was 3.5. All patients had stage IV disease and 7 of 9 patients required bridging therapy. Grade-1 cytokine release syndrome (CRS) occurred in 6 of 8 patients, and no patient experienced immune effector cell-associated neurotoxicity syndrome ( ICANS). Among all patients, only one dose of tocilizumab was administered to one subject, and no steroids were given. With a median follow-up of 12 months from time of CART19/20 infusion (range: 4+ to 24+ months), 7 of 8 of patients remain in a complete remission. Median PFS and OS were not reached, and all patients with a complete remission demonstrate ongoing B-cell aplasia. Conclusions: This study demonstrates that CART19/20 cells are safe and effective in patients with relapsed/refractory NHL and potentially obviates the challenges of the commonest causes of relapse after CAR-T cell therapy by means of modifying TN/MEM cells and dual-antigen targeting, respectively. Given the strong safety and response observed, dose escalation was completed with the second dosing level (DL2) of 200 x 106 CAR-positive cells, and DL1 of 50 x 106 CAR-positive cells was chosen as the therapeutic dose for future trial expansion. Clinical trial information: NCT04007029.

Quantitative self-assembly prediction yields targeted nanomedicines

Development of targeted nanoparticle drug carriers often requires complex synthetic schemes involving both supramolecular self-assembly and chemical modification. These processes are generally difficult to predict, execute, and control. We describe herein a targeted drug delivery system that is accurately and quantitatively predicted to self-assemble into nanoparticles based on the molecular structures of precursor molecules, which are the drugs themselves. The drugs assemble with the aid of sulfated indocyanines into particles with ultrahigh drug loadings of up to 90%. We devised quantitative structure-nanoparticle assembly prediction (QSNAP) models to identify and validate electrotopological molecular descriptors as highly predictive indicators of nano-assembly and nanoparticle size. The resulting nanoparticles selectively targeted kinase inhibitors to caveolin-1-expressing human colon cancer and autochthonous liver cancer models to yield striking therapeutic effects while avoiding pERK inhibition in healthy skin. This finding enables the computational design of nanomedicines based on quantitative models for drug payload selection.