ABSTRACT
Introduction: Adult T-cell leukemia lymphoma (ATLL) is a rare hematologic malignancy caused by human T-cell lymphotropic virus (HTLV-1) with dismal cure rates and poor response to conventional chemotherapy. Allogeneic Hematopoietic Stem Cell Transplantation (AlloSCT) is the only therapeutic option which may offer the chance of long-term remission and cures in a subset of patients. We sought to investigate the outcomes of transplantation in one of the largest cohorts in North America. Methods: A retrospective chart review study was conducted using the North-American ATLL and the Hematopoietic Precursor Cell transplantation databases at Montefiore Medical Center from 2011 to 2020. Variables collected include age, sex, ethnicity, ATLL subtype, molecular profile, previous treatments, conditioning regimens, type of transplant, immunosuppressive regimen, progression free survival (PFS) post-transplant and overall survival (OS) post-transplant. Results: Fourteen patients with ATLL who received an AlloSCT from 2011-2020 were identified. Fifty-seven percent (8/14) of patients were male. Seventy-one percent (10/14) of patients were African American and twenty-nine percent (4/14) were Hispanic. Median age was 51 years. Sixty-four percent (9/14) of patients had Stage IV disease at the time of diagnosis. Forty-three percent (6/14) patients had acute and fifty-seven percent (8/14) had lymphomatous ATLL. Almost all patients (92%) were treated initially with EPOCH combination chemotherapy. Twenty-eight percent (4/14) of patients received interferon/zidovudine as bridge-to-transplant. Fifty-seven percent (8/14) of patients achieved complete remission (CR) prior to AlloSCT, 7% (1/14) were in partial remission, and 28% (4/14) were relapsed or refractory. Forty-three percent (6/14) of patients received SCT from a matched-related donor (MRD), 36% (5/14) from a haplo-identical donor and 21% (3/14) from a matched-unrelated donor (MUD). Ninety-three percent (13/14) of patients received a reduced-intensity conditioning (RIC) regimen pre-transplantation. Seven percent (1/14) received a myeloablative conditioning (MAC) regimen. RIC regimens consisted of fludarabine with melphalan +/- anti-thymocyte globulin (ATG) or fludarabine with cyclophosphamide with total-body irradiation in doses less than 500 cGy. Patients receiving haplo-identical SCT also received post-transplant cyclophosphamide (PTCy) for prevention of graft vs host disease (GVHD). The MAC regimen used included busulfan with cyclophosphamide at myeloablative doses. Twenty-eight percent (4/14) of patients relapsed post-alloSCT with a median relapse-free survival of 6 months (range 4-18 months). The median OS of the whole cohort was 27 months (8-82 months). Graft-versus-host disease (GVHD) developed in 28% (4/14) percent of patients. The most common manifestation was skin GVHD. Fifty-percent (7/14) of the patients are surviving to-date. Transplant-related mortality (TRM) at day 100 was 21% (3/14) of patients. Causes of death were complex and included several diagnoses in certain patients. The most frequent diagnoses associated with death were infection (28%), graft failure (14%), GVHD (14%), veno-occlusive disease of the liver (VOD) (7%), disease progression (14%) and unknown due to patient lost to follow-up (14%). The main infectious events included fungal (2), bacterial (1), and COVID-19 (1) infection. Forty-three percent (6/14) of patients remain in complete remission to date. Conclusions: Allogeneic Stem Cell Transplantation offers long-term survival with a TRM of 21% in a disease with an inherently dismal prognosis. AlloSCT using several graft sources, is thus, a safe and well tolerated treatment modality and offers long term remissions. Disclosures: Steidl: Pieris Pharmaceuticals: Consultancy;Aileron Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding;Bayer Healthcare: Research Funding;Stelexis Therapeutics: Consultancy, Current equity holder in private company, Membership on an entity's Board of Directors or advi ory committees. Verma: BMS: Consultancy, Research Funding;acceleron: Consultancy, Honoraria;Janssen: Research Funding;Medpacto: Research Funding;stelexis: Current equity holder in private company. Janakiram: ADC Therapeutics, FATE therapeutics, TAKEDA pharmaceuticals: Research Funding.
ABSTRACT
Background: Adoptive immunotherapy using CD19-targeted Chimeric Antigen Receptor T-cells (CAR-T) has revolutionized the treatment of relapsed/refractory diffuse large B-cell lymphoma (DLBCL). We have demonstrated the efficacy of FDA-approved axicabtagene ciloleucel (Yescarta) in a multiethnic New York City underserved population with 80% complete response (CR) rate in the first ten patients treated at our institution (Abbasi et al., 2020). There is limited data on the propensity of infections and lymphohematopoietic reconstitution after Day 30 (D30) following CAR-T cell therapy. In this study, we evaluated the prevalence and nature of infectious complications in an expanded cohort of DLBCL patients treated with CD19 CAR-T therapy and its association with the dynamics of leukocyte subpopulation reconstitution post-CAR-T cell therapy. Methods: We conducted a retrospective study of patients who received CAR-T therapy at our institution between 2018-2020. Variables collected include patient demographics, absolute neutrophil (ANC), lymphocyte (ALC) and monocyte counts (AMC) at Day 30, hematologic reconstitution (ANC≥ 1500/µL) at Day 90 (D90), presence or absence of infections after D30 by clinical and/or microbiological parameters. Associations between presence of infection and D30 ANC, ALC, AMC, ANC/ALC ratio, AMC/ALC ratio were assessed using Kruskal-Wallis test. Association between infection and hematologic reconstitution at D90 was done using Chi-square test. Kaplan-Meier curves with log-rank test were used to evaluate overall survival (OS) and progression-free survival (PFS). Results: Nineteen patients were evaluated in our study, consisting of 42% (8) Hispanic, 32% (6) Caucasian, 21% (4) African-American, and 5% (1) Asian subjects. Based on clinical and microbiologic data, 47% (9) developed an infection after D30 (infection group) while 53% (10) of subjects remained infection-free after D30 (non-infection group). The most common infection type observed was viral (11 patients) followed by bacterial (8 patients) and fungal (3 patients) (Table 1). Of 25 total infectious events, 44% (11) were grade 1 or 2 and 48% (12) were grade 3 with 10 being viral in etiology. Two deaths occurred due to an infectious process. Three patients tested SARS-CoV-2 positive and were hospitalized with COVID-19 pneumonia. Median OS and PFS has not been reached in either group. To determine the kinetics of lymphohematopoietic reconstitution and its association with infection risk, we evaluated the relationship between cytopenias and rates of infection after D30. Notably, compared to non-infection group, infection group had a higher median ALC (1000/µL vs 600/µL p=0.04), a lower median ANC/ALC ratio (1.4 vs 4.5 p<0.01) and a lower median AMC/ALC at D30 (0.36 vs 1.33, p=0.01) (Table 2). In addition, patients in the infection group had a lower rate of hematologic reconstitution (ANC >1500/µL) at D90. We observed that only 22% (2) of patients had recovered ANC > 1500/µLin the infection group as opposed to 80% (8) in the non-infection group at D90 (p= 0.038). Rates of cytokine release syndrome (CRS) were comparable between the two groups (55.6% vs 70% p=0.52). Surprisingly, rates of immune-effector cell associated neurotoxicity syndrome (ICANS) was lower (55.6%) in the infection group compared to (90%) non-infection group (p=0.09). Fourteen of 19 patients had follow-up over one year, of which 8 (57%) remained in complete remission (CR). Conclusions: We demonstrate an infection rate of 47% (9) beyond D30 in patients undergoing CD19 CAR-T. Increased ALC, lower ANC/ALC and AMC/ALC ratios at D30 may be predictive of infectious complications. Median OS has not been reached in our cohort. Given the potential clinical impact, our observations should be corroborated using larger datasets. [Formula presented] Disclosures: Steidl: Pieris Pharmaceuticals: Consultancy;Bayer Healthcare: Research Funding;Stelexis Therapeutics: Consultancy, Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees;Ai eron Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Janakiram: ADC Therapeutics, FATE therapeutics, TAKEDA pharmaceuticals: Research Funding. Verma: BMS: Consultancy, Research Funding;acceleron: Consultancy, Honoraria;Janssen: Research Funding;stelexis: Current equity holder in private company;Medpacto: Research Funding.