Point of care CD19 chimeric antigen receptor (CAR) T-cells for relapsed/refractory acute myeloid leukemia (AML) with aberrant CD19 antigen expression.

Relapsed/refractory (r/r) acute myeloid leukemia (AML) is associated with poor prognosis. CD19 is a B-cell marker, is aberrantly expressed in AML, mostly with t(8; 21)(q22; q22.1). Here we report the results of a phase 2 study giving point of care produced CD19 CAR T- cells for r/r AML with aberrant expression of CD19 (NCT04257175). Lymphodepletion included fludarabine and cyclophosphamide The response was evaluated by bone marrow (BM) aspiration on day 28. Six patients (5 adults and 1 child) were included. Median number of previous chemotherapy lines was 4 (range, 3-8) and four patients received CAR T-cells 8-18 months post allogeneic hematopoietic stem cell transplantation (allo-HSCT). Cytokine release syndrome (CRS) of any grade occurred in all patients, and 1 patient had grade 3 CRS. Immune effector cell-associated neurotoxicity syndrome (ICANS) occurred in 2 patients at low grades. Tocilizumab was administered to 2 patients and corticosteroids to 3 patients. Four patients achieved a complete remission (CR), while 2/6 progressed (PD). Three patients (2 with CR and 1 with PD) underwent allo-HSCT (it was the second transplant in 2) 2-5 months post CAR T-cells infusion. The median duration of response in patients achieving CR was 8.5 (range; 3-14) months. However, all patients eventually died within 5 (1-18) months. In conclusion, CD19 CAR T- cell treatment for AML is feasible and safe. However, the response is short and should be followed by allo-HSCT. Hopefully, future long term results will be improved by combining the CAR T- cell therapy with the emerging novel effective anti-leukemic compounds.

Anti-CD19 chimeric antigen receptor T-cell therapy has less efficacy in Richter transformation than in de novo large B-cell lymphoma and transformed low-grade B-cell lymphoma.

The activity of anti-CD19 CAR T cell therapy in chronic lymphocytic leukemia (CLL) with Richter's transformation (RT) to aggressive large B cell lymphoma (LBCL) is largely unknown. In a multicenter retrospective study, we report the safety and efficacy of CAR T cell therapy in patients with RT (n=30) compared to patients with aggressive B cell lymphoma (n=283) and patients with transformed indolent Non-Hodgkins Lymphoma (iNHL) (n=141) between April 2016 and January 2023. Two-thirds of patients received prior therapy for CLL before RT and 89% of them received B-cell receptor and B-cell lymphoma 2 (BCL-2) inhibitors. Toxicities of CAR T cell therapy in RT were similar to other lymphomas, with no fatalities related to cytokine release syndrome or immune effector-cell associated neurotoxicity synderome. The 100-day overall response rate and complete response rates in patients with RT were 57% and 47%, respectively. With a median follow up of 19 months, the median overall survival (OS) was 9.9 months in patients with RT compared to 18 months in de-novo LBCL and not reached in patients with transformed iNHL. The OS at 12 months was 45% in patients with RT compared with 62% and 75% in patients with de novo LBCL and transformed iNHL, respectively. In a multivariate analysis, worse OS was associated with RT histology, elevated LDH, and more prior lines of therapy. CAR T cell therapy can salvage a proportion of patients with CLL and RT exposed to prior targeted agents; however, efficacy in RT is inferior compared to de novo LBCL and transformed iNHL.

Liver stiffness measurements predict Sinusoidal Obstructive Syndrome after hematopoietic stem cell transplantation.

Sinusoidal Obstructive Syndrome (SOS) is a life-threatening complication after hematopoietic stem-cell transplantation (HSCT), characterized by post-sinusoidal portal hypertension. FibroScan is used to assess portal hypertension non-invasively. We assessed transient elastography (TE) applicability in diagnosing SOS. The study included 27 adult patients, 11 underwent TE for high SOS risk pre-HSCT, 17 underwent TE post-HSCT due to bilirubin ≥2 mg/dl with no definite diagnosis of SOS. The first group had median Liver Stiffness Measurement (LSM) of 7.4 kPa (range, 3.3-22.5). Based on LSM results, conditioning regimen was modified for six patients and two of them developed SOS. Only one patient who did not have protocol adjustment experienced SOS. No patient with LSM < 7 kPa developed SOS. The second group had median LSM of 7.7 kPa (4.4-31.5). Median LSM after HSCT was significantly higher in patients who subsequently developed established SOS (n = 10) compared to patients who did not (n = 8), with values of 10.7 kPa (5.6-31.5) and 5.9 kPa (4.4-13.8), respectively (p = 0.02). An LSM cut-off of 7.5 kPa had a sensitivity and specificity of 75 and 80% for diagnosing SOS. In conclusion, pre-HSCT LSM can help adjustment of conditioning regimen in patients with high-risk for SOS. Post-HSCT LSM can help in early diagnosis of SOS.

Fecal microbiota transplantation in capsules for the treatment of steroid refractory and steroid dependent acute graft vs. host disease: a pilot study.

Acute graft-versus-host disease (aGvHD) is a serious complication of allogeneic hematopoietic stem-cell transplantation with limited treatment options. The gut microbiome plays a critical role in aGvHD pathogenesis. Fecal microbiota transplantation (FMT) has emerged as a potential therapeutic approach to restore gut microbial diversity. In this prospective pilot study, 21 patients with steroid-resistant or steroid-dependent lower gastrointestinal aGvHD received FMT in capsule form. At 28 days after the first FMT, the overall response rate was 52.4%, with 23.8% complete and 28.6% partial responses. However, sustained responses were infrequent, with only one patient remaining aGvHD-free long-term. FMT was generally well-tolerated. Microbiome analysis revealed dysbiosis in pre-FMT patient stool samples, with distinct microbial characteristics compared to donors. Following FMT, there was an increase in beneficial Clostridiales and a decrease in pathogenic Enterobacteriales. These findings highlight the potential of FMT as a treatment option for steroid-resistant aGvHD. Trial registration number NCT #03214289.

Point-of-care anti-CD19 chimeric antigen receptor T-cell therapy for relapsed/refractory follicular lymphoma.

Patients with relapsed/refractory follicular lymphoma (R/R-FL) often require multiple treatment lines. We performed a phase 1b/2 single-center clinical trial of autologous point-of-care anti-CD19 chimeric antigen receptor (CAR) T-cells in R/R-FL patients treated patients with ≥ 2 treatment lines. All 26 patients enrolled received CAR T-cell infusion at a median of 11 days after leukapheresis. Seventy-seven percent of patients had POD24. At enrollment, disease stage was III-IV in 85% of the patients, 77% had high-risk FLIPI score, and 77% had progressive disease. Grade III-IV cytokine release and immune effector cell-associated neurotoxicity syndromes occurred in 12% and 16% of the patients, respectively. Overall response rate at 1-month was 88%. The median follow-up was 15.4 months. One-year overall and progression-free survival were 100% and 63%, respectively. In conclusion, point-of-care CAR T-cell, manufactured within 11 days, induced a high response rate with an acceptable safety profile in patients with high-risk R/R-FL.

Outcomes of first therapy after CD19-CAR-T treatment failure in large B-cell lymphoma.

Persistence or recurrence of large B-cell lymphoma after CD19-CAR-T is common, yet data guiding management are limited. We describe outcomes and features following CAR-T treatment failure. Of 305 adults who received CD19-CAR-T, 182 experienced disease recurrence or progression (1-year cumulative incidence 63% [95%CI: 57-69]). Of 52 post-CAR-T biopsies evaluated by flow cytometry, 49 (94%) expressed CD19. Subsequent anti-cancer treatment was administered in 135/182 (74%) patients with CAR-T treatment failure. Median OS from the first post-CAR-T treatment was 8 months (95%CI 5.6-11.0). Polatuzumab-, standard chemotherapy-, and lenalidomide-based treatments were the most common approaches after CAR-T. No complete responses (CRs) were observed with conventional chemotherapy, while CR rates exceeding 30% were seen following polatuzumab- or lenalidomide-based therapies. Factors associated with poor OS among patients treated post-CAR-T were pre-CAR-T bulky disease (HR 2.27 [1.10-4.72]), lack of response to CAR-T (2.33 [1.02-5.29]), age >65 years (HR 2.65 [1.49-4.73]) and elevated LDH at post-CAR-T treatment (HR 2.95 [1.61-5.38]). The presence of ≥2 of these factors was associated with inferior OS compared to ≤1 (56% vs. 19%). In this largest analysis to date of patients who progressed or relapsed after CD19-CAR-T, survival is poor, though novel agents such as polatuzumab and lenalidomide may have hold promise.

Allogeneic Hematopoietic Cell Transplantation after Chimeric Antigen Receptor T Cell Therapy in Large B Cell Lymphoma.

Anti-CD19 chimeric antigen receptor T cell (CAR-T) therapy has transformed the care of patients with relapsed/refractory large B cell lymphoma (LBCL). However, approximately 60% of CAR-T recipients ultimately will experience disease recurrence or progression. Salvage therapies after CAR-T treatment failures are of limited efficacy and have a short duration of response. The objective of the present study was to evaluate the role of allogeneic hematopoietic cell transplantation (allo-HCT) after CAR-T therapy in LBCL patients. This was a multicenter observational study reporting the outcome of 39 adult LBCL patients who underwent allo-HCT following anti-CD19 CAR-T therapy. The median patient age was 47 years (range, 20 to 68 years). HLA-matched sibling, HLA-matched unrelated, and alternative donors were used in 36%, 36%, and 28% of transplantations, respectively. Conditioning regimens were primarily of low or intermediate intensity. Disease status at allo-HCT was complete response in 41%, partial response in 38%, and progressive disease in 21%. Allo-HCT was performed at a median of 127 days (range, 82 to 206 days) after CAR-T therapy. A high incidence of hepatic toxicity (28%), including sinusoidal obstruction syndrome (15.4%; 95% confidence interval; [CI], 6.2% to 28.5%), was observed. The 1-year cumulative incidence of grade II-IV and grade III-IV acute graft-versus-host disease (GVHD) was 38.5% (95% CI, 23.2% to 53.6%) and 15.4% (95% CI, 6.1% to 28.5%), respectively. The 2-year cumulative incidence of moderate-severe chronic GVHD was 11.1% (95% CI, 3.3% to 24.3%). Overall, 2-year nonrelapse mortality and relapse/progression incidence were 26% (95% CI, 13% to 41%) and 43% (95% CI, 27% to 59%), respectively. With a median follow-up of 32 months, the 2-year overall survival (OS) and progression-free survival (PFS) were 45% (95% CI, 31% to 66%) and 31% (95% CI, 19% to 50%), respectively. In multivariable analyses, pre-HCT elevated lactate dehydrogenase level and transformed lymphoma were predictive of OS and PFS, respectively. Our data suggest that allo-HCT after anti-CD19 CAR-T treatment failure is feasible with a relatively promising efficacy but possibly high toxicity rate.

Second hematopoietic stem cell transplantation as salvage therapy for relapsed acute myeloid leukemia/myelodysplastic syndromes after a first transplantation.

Second allogeneic hematopoietic stem-cell transplantation (HSCT2) is a therapeutic option for patients with acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) relapsing after a first transplant (HSCT1). However, patients allocated to HSCT2 may be a selected group with better prognosis and the added efficacy of HSCT2 is not well established. We retrospectively analyzed 407 consecutive patients with relapsed AML/MDS after HSCT1. Sixty-two patients had HSCT2 (15%) and 345 did not. The 2-year cumulative incidence rates of non-relapse mortality and relapse after HSCT2 were 26% (95% confidence interval [95% CI]: 17-39%) and 50% (95% CI: 39-65%), respectively. The 5-year overall survival rates were 25% (95% CI: 14-36%) and 7% (95% CI: 4-10%) in the HSCT2 and no-HSCT2 groups, respectively. Multivariate analysis identified female gender (hazard ratio [HR]=0.31, P=0.001), short remission duration after HSCT1 (HR=2.31, P=0.05), acute graft-versus-host disease after HSCT1 (HR=2.27, P=0.035), HSCT2 from a haplo-identical donor (HR=13.4, P=0.001) or matched unrelated donor (HR=4.53, P=0.007) and relapse after HSCT1 in earlier years (HR=2.46, P=0.02) as factors predicting overall survival after HSCT2. Multivariate analysis of all patients including HSCT2 as a timedependent variable identified relapse within 6 months after HSCT1 (HR=2.32, P<0.001), acute graft-versus-host disease before relapse (HR=1.47, P=0.005), myeloablative conditioning in HSCT1 (HR=0.67, P=0.011), female gender (HR=0.71, P=0.007), relapse in earlier years (HR=1.33, P=0.031) and not having HSCT2 (HR=1.66, P=0.010) as predictive of overall survival after relapse. In conclusion, HSCT2 is associated with longer survival compared to non-transplant treatments and may be the preferred approach in a subset of patients with relapsed AML/MDS after HSCT1.

Point-of-care CAR T-cell therapy as salvage strategy for out-of-specification tisagenlecleucel.

Tisagenlecleucel (tisa-cel) is an anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved for patients with relapsed/refractory large B-cell lymphoma. Outcomes of patients with out-of-commercial specification (OOS) CAR T products are not well characterized. We therefore assessed 37 adult patients who underwent leukapheresis for tisa-cel therapy in a single center. In nine (24%) patients, manufactured tisa-cel was considered OOS. Three of them (33%) received tisa-cel after institutional review board approval; 2/9 (22%) did not receive tisa-cel due to disease progression; and 4/9 (44%) received academic point-of-care (POC) CAR T-cell as salvage therapy, at a median of 35 days following OOS notification. Three of those four patients achieved a complete response. In univariate analysis, risk factors for OOS were ≥ 4 prior therapies or previous bendamustine exposure. In conclusion, we report high OOS incidence of 24% in real-life setting. Forty-four percent of those patients received POC CAR T-cell as salvage therapy.

Point-of-care anti-CD19 CAR T-cells for treatment of relapsed and refractory aggressive B-cell lymphoma.

Anti CD19 chimeric antigen receptor (CAR) T-cell therapy has transformed the care of relapsed and refractory aggressive B-cell lymphoma. However, financial toxicity and manufacturing time represent barriers to its widespread implementation. Study applicability, toxicity, and efficacy of a locally produced autologous CD19-directed CAR T-cell product were studied. We performed a phase 1b/2 clinical trial with a point-of-care (POC) CAR T-cell product that contains a CD28 costimulatory domain. Adult patients with aggressive B-cell lymphoma or transformed low-grade lymphoma who received at least 2 prior regimens were eligible. A total of 73 patients, with a median age of 49 years, met inclusion criteria. CAR T-cell production time from apheresis was 10 days (interquartile range 10-11), negating the need for bridging chemotherapy. Overall and complete response rates were 62.5% and 37.5%. Median progression-free and overall survival were 3.7 and 12.1 months, respectively. Overall and progression-free survival at 12 months were 52.1% (confidence interval [CI]: 40.8%-66.5%) and 40% (CI: 30%-53.7%), respectively. Patients who achieved response had longer progression-free and overall survival. Grade 3-4 cytokine release syndrome was observed in 9.5% of the patients, and immune effector cell-associated neurotoxicity syndrome grade 3-4 in 21.9%. No deaths occurred due to CAR T-cell toxicity. Fifteen patients (20%) underwent allogeneic stem cell transplantation at a median time of 60 days after CAR T-cell therapy; 8 were alive at last follow-up. Of the 6 patients who underwent the transplantation in complete response 2 deceased because of toxicity. POC CAR T-cells are a feasible therapeutic option in aggressive B-cell lymphoma. They provide good efficacy while minimizing production time and the need for bridging therapy.