Lisocabtagene Maraleucel (liso-cel) for Treatment of Second-Line Transplant Noneligible (TNE) Relapsed/Refractory (R/R) Aggressive Non-Hodgkin Lymphoma (NHL): Initial Results from the PILOT Study

Background: Patients (pts) with R/R aggressive large B cell NHL who fail first-line therapy with immunochemotherapy and are ineligible for high-dose chemotherapy and hematopoietic stem cell transplantation (HSCT) have a poor prognosis. Available treatment options include platinum/gemcitabine-based or bendamustine-based regimens in combination with rituximab, with or without radiotherapy, or clinical trials. However, long-term outcomes remain poor due to lack of a curative option. Liso-cel is an investigational, anti-CD19, defined composition, 4-1BB CAR T cell product administered at target doses of CD4+ and CD8+ CAR T cells. In the ongoing TRANSCEND NHL 001 study of liso-cel as third- or later-line treatment for pts with R/R large B cell NHL, preliminary data showed high overall response rates with a low incidence of grade ≥3 cytokine release syndrome (CRS) and neurological events (NEs) (Abramson et al, ASCO 2018). The open-label, phase 2 PILOT study is assessing the safety and efficacy of liso-cel as second-line therapy in TNE pts (NCT03483103). PILOT is the first study evaluating CAR T cell therapy focusing on this pt population.

Methods: Eligible pts had R/R large B cell NHL (diffuse large B cell lymphoma [DLBCL], not otherwise specified [NOS], de novo or transformed indolent NHL, high-grade lymphoma with MYC and BCL2 and/or BCL6 [double/triple-hit lymphoma], or follicular lymphoma (FL) grade 3B) and had received only 1 prior line of immunochemotherapy containing an anthracycline and a CD20-targeted agent (eg, R-CHOP). Pts had to be deemed ineligible for high-dose chemotherapy followed by HSCT by meeting at least 1 of the following TNE criteria while still fulfilling the criteria for CAR T cell therapy: age ≥70 years, ECOG PS of 2, and/or impaired pulmonary (DLCO ≤60% but SaO₂ ≥92% on room air and CTCAE ≤1 dyspnea), cardiac (LVEF ≥40% and <50%), renal (creatinine clearance >30 and <60 mL/min), or hepatic function (AST/ALT >2 and ≤5 ×ULN). Liso-cel was administered at a target dose of 100×10⁶ CAR+ T cells after lymphodepletion (LD) with fludarabine/cyclophosphamide for 3 days. Pts could be treated as outpatients at the investigator's discretion.

Results: At data cutoff, 10 pts had been leukapheresed, and 9 pts had LD followed by liso-cel infusion; 1 pt is awaiting liso-cel treatment. Liso-cel was manufactured successfully in all pts. Five pts were infused and monitored as outpatients. Median age was 71 (range, 64-79) years; 5 pts were male. Histology included DLBCL NOS (n=7) and transformed FL (n=2); 2 pts had triple-hit, one of whom had transformed from FL. Five pts had relapsed from, and 4 pts had disease refractory to, prior therapy. Median SPD and LDH were 26.6 cm² and 201 U/L, respectively. Four pts had high tumor burden with SPD ≥50 cm² (n=4) and/or LDH ≥500 U/L (n=1). The median Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI) score was 3 (range, 0-3). Six pts had 1 or more treatment-emergent adverse events (TEAEs) grade ≥3, which were primarily cytopenias. Three pts had prolonged grade ≥3 cytopenias at Day 29. Two pts had infections of any grade; no pts had grade ≥3 infections. No pts had CRS or NEs, and no pts received tocilizumab, corticosteroids, or vasopressors. There were no cases of macrophage activation syndrome, tumor lysis syndrome, infusion reactions, or grade 5 TEAEs. Among the 5 pts treated and monitored as outpatients, none were admitted to hospital for adverse events within the first 29 days post liso-cel infusion. All 9 pts achieved an objective response. Four pts achieved complete response; all are ongoing. Five pts achieved partial response (PR), with 2 PRs ongoing. Results were similar in inpatient vs outpatient pts. Median follow-up was 3.5 months. Median (range) time to peak CAR T cell expansion was 10 (7-21) days.

Conclusions: These preliminary safety and efficacy data from the ongoing phase 2 PILOT study suggest that liso-cel can be successfully administered, including in the outpatient setting, as second-line therapy in pts with R/R aggressive B cell NHL who were ineligible for high-dose chemotherapy and HSCT by prespecified criteria. Updated safety and efficacy data with longer follow-up will be presented.