Outcomes of Autologous Hematopoietic Cell Transplantation in Diffuse Large B Cell Lymphoma Refractory to Firstline Chemoimmunotherapy

Autologous stem cell transplant in fit patients with refractory or early relapsed diffuse large B-cell lymphoma that responded to salvage chemotherapy

Chimeric antigen receptor T-cell therapy is the new standard of care in fit patients with refractory or early relapsed diffuse large B-cell lymphoma (DLBCL). However, there may still be a role for salvage chemotherapy (ST) and autologous stem cell transplant (ASCT) in certain circumstances (e.g., lack of resources for chimeric antigen receptor T-cell therapy, chemosensitive relapses). We retrospectively studied 230 patients with refractory or early relapsed DLBCL who underwent ST and ASCT. The median line of ST was one (range, 1-3). Best response before ASCT was complete response in 106 (46%) and partial response in 124 (54%) patients. The median follow-up after ASCT was 89.4 months. The median progression-free (PFS) and overall survival (OS) were 16.1 and 43.3 months, respectively. Patients relapsing between 6 to 12 months after frontline therapy had a numerically better median PFS (29.6 months) and OS (88.5 months). Patients who required one line of ST, compared to those requiring more than one line, had a better median PFS (37.9 vs. 3.9 months; P=0.0005) and OS (68.3 vs. 12.0 months; P=0.0005). Patients who achieved complete response had a better median PFS (71.1 vs. 6.3 months; P<0.0001) and OS (110.3 vs. 18.9 months; P<0.0001) than those in partial response. Patients who achieved complete response after one line of ST had the most favorable median PFS (88.5 months) and OS (117.2 months). Post-ASCT survival outcomes of patients with refractory or early relapsed DLBCL appeared reasonable and were particularly favorable in those who required only one line of ST to achieve complete response before ASCT, highlighting the role of this procedure in select patients with chemosensitive disease.

Elhassan TA, Akhtar S. Outcomes of Autologous stem cell transplantation in patients with primary refractory Diffuse Large B-cell lymphoma who demonstrate chemosensitivity to salvage chemotherapy

Rituximab with anthracycline-based combination frontline chemoimmunotherapy can cure 50-60% of patients with diffuse large B-cell lymphoma (DLBCL). However, studies on the outcomes of patients with DLBCL who experience partial response (PR), stable or progressive disease in response to frontline rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (RCHOP) therapy are limited, as are data on the outcomes of high-dose chemotherapy (HDC) and autologous stem cell transplantation (ASCT) in patients with primary refractory DLBCL who demonstrate chemosensitivity to salvage chemotherapy (SC). We assessed the latter among 184 patients, 144 of whom started SC, with 84 responding and 72 receiving HDC-ASCT. The 5-year survival rate was 58.9%; the median overall survival (OS) was not reached. The difference in response to SC (partial response versus complete response) was significant, with higher 2- and 5-year OS rates in patients with CR (78.1% and 74.9%, respectively) than in those with PR (55.3% and 47%, respectively). The median OS for the whole group was 15 months and particularly patients who had progressive disease after frontline R-CHOP had dismal outcomes. Our study suggests that in patients with primary refractory DLBCL without initial progressive disease after frontline R-CHOP, the depth of response to SC before HDC-ASCT is predictive of relapse.

Early failure is still a poor prognostic factor in patients with relapsed or refractory large B-cell lymphoma in the era of CAR T-cell therapy

Patients with refractory or relapsed (R/R) large B-cell lymphoma (LBCL) refractory to first-line chemotherapy or with early relapse have poor outcomes. While chimeric antigen receptor (CAR) T-cell therapy has impressive efficacy after two or more lines of chemotherapy, it's still uncertain if these outcomes remain consistent in the context of third-line CAR T-cell therapy. We conducted a retrospective study of 107 R/R LBCL patients. Patients with relapse 12 months or more after their first-line chemoimmunotherapy (late failure: n = 25) had significantly longer overall survival (OS) than patients with refractory disease or relapse within 12 months (early failure: n = 82) (median OS: not achieved vs. 18.4 months; P < 0.001). Among patients who proceeded to autologous hematopoietic stem-cell transplantation (auto-HSCT), those with late failure had significantly longer event-free survival (EFS) than those with early failure (median EFS: 26.9 vs. 3.1 months; P = 0.012). However, no significant difference in EFS was detected among patients who underwent CAR T-cell therapy (median EFS: not reached vs. 11.8; P = 0.091). Cox regression with restricted cubic spline demonstrated that timing of relapse had significant impact on EFS in patients with auto-HSCT but not in patients with CAR T-cell therapy. Of patients who were scheduled for CAR T-cell therapy, those with late failure were significantly more likely to receive CAR T-cell therapy than those with early failure (90% vs. 57%; P = 0.008). In conclusion, patients with early failure still experienced poor outcomes after the approval of third-line CAR T-cell therapy.

Augmented ICE in Patients With Poor-Risk Refractory and Relapsed Lymphomas

BACKGROUND

In patients with relapsed/refractory lymphoma after first line therapy, chemosensitivity to salvage chemotherapy is the main determinant of outcome pre-autologous stem cell transplant . With novel therapies not yet widely available and poor responses to conventional dose salvage therapy such as ifosfamide, carboplatin, and etoposide (ICE) in patients with early relapse within 12 months and primary refractory disease, there is capacity to dose intensify ifosfamide and etoposide (augmented ICE).

METHODS

We retrospectively evaluated patients who received augmented ICE between 2010 and 2020 and report on response, deliverability, toxicities, and outcome. Patients were transplant eligible with diffuse large-B cell lymphoma (DLBCL) or Hodgkin lymphoma (HL) with refractory disease or relapse within 12 months. Dose of augmented ICE versus standard ICE was ifosfamide 10 versus 5 g/m² and etoposide 600 versus 300 mg/m². Carboplatin dose with a calculated area under curve of 5 was unchanged. Anti-CD20 monoclonal antibody was given in patients with CD20 positive lymphoma. Responding patients who achieved complete response or partial response proceeded to transplant.

RESULTS

Twenty-one patients with DLBCL (n = 13) and HL (n = 8) received augmented ICE. Nineteen of 21 completed 2 cycles. Overall response rates were 85% (DLBCL) and 100% (HL). Most patients required transfusion, 2 developed reversible ifosfamide encephalopathy and 86% febrile neutropenia. Eighteen patients proceeded to transplant. 5-year overall survival (OS) and progression-free survival (PFS) in DLBCL were 62% and 45%, and in HL, 100% and 88%, respectively.

CONCLUSION

Augmented ICE is associated with high response rate and transplant realization at the expense of toxicity.

Impact of Implementing a Bendamustine-Based Conditioning Regimen on Outcomes of Autologous Stem Cell Transplantation in Lymphoma while Novel Cellular Therapies Emerge

With the advent of new cellular and targeted therapies, treatment options for relapsed and refractory (r/R) lymphomas have multiplied, and the optimal approach offering the best outcomes remains a matter of passionate debate. High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is still considered a treatment option for patients with chemosensitive lymphoma when cure is the expected goal. The myeloablative conditioning regimen preceding the stem cell infusion is considered the effective component of this approach. Carmustine (BCNU)-based preparative regimens, such as BEAM and BEAC, are considered the standard of care and have shown efficacy and low nonrelapse mortality (NRM). Comparative studies between conditioning regimens have failed to identify a better option. After a BCNU drug shortage in Canada followed by a steep increase in price, we elected to substitute BCNU for bendamustine (benda) in the preparative regimen. The purpose of this substitution was to improve response while preserving safety and controlling costs. From May 2015 to May 2018, a total of 131 consecutive lymphoma patients received benda-EAM conditioning. These patients were compared with 96 consecutive patients who received BCNU-based conditioning from January 2012 to May 2015. Apart from conditioning, supportive care measures were the same in the 2 groups. Patients receiving benda were older (55.7 years versus 51.1 years; P = .002). The development of grade ≥3 mucositis was more frequent with benda conditioning (39.5% versus 7.8%; P < .001) leading to a greater requirement for parenteral nutrition (48.9% versus 21.9%; P < .001). A transient creatinine increase >1.5 times the upper limit of normal (15.3% versus 4.2%; P < .008) and intensive care unit admission (6.9% versus 1.1%; P < .029) were more frequent with benda; however, there were no between-group differences in cardiac, pulmonary, or liver toxicity and NRM. With a median follow-up of 48 months for the benda group and 60 months for the BCNU group, benda was associated with significantly better progression-free survival (71% versus 61%; P = .040; hazard ratio [HR], 1.6; 95% confidence interval [CI], 1.0 to 2.7) and overall survival (86% vs 71%; P = .0066; HR, 2.6; 95% CI, 1.3 to 5.4) compared with BCNU-based conditioning regimens. While novel therapies emerge, our study demonstrates that benda-EAM is safe and effective and should be considered a valid alternative to BCNU conditioning to improve outcomes of patients with chemosensitive r/R lymphomas undergoing ASCT.

Patterns of Utilization and Outcomes of Autologous Stem Cell Transplantation and Chimeric Antigen Receptor T-Cell Therapy in Relapsed or Refractory Diffuse Large B-cell Lymphomas with MYC and BCL2 and/or BCL6 Rearrangements

BACKGROUND

Patients with Diffuse Large Bcell Lymphoma (DLBCL) with MYC and BCL2 and/or BCL6 gene rearrangements [double-hit lymphoma/triple-hit lymphoma (DHL/THL)] have poor prognosis in the relapsed/refractory setting.

METHODS

We utilized a real-world deidentified database of DLBCL patients and report patterns of therapy utilization in relapsed/refractory DLBCL. We used log-rank test to compare real-world overall survival (rwOS) among DHL and non-DHL subgroups for CAR Tcell therapy or ASCT respectively, stratified for prior lines of therapy.

RESULTS

Of all 7,877 patients with DLBCL, 367 patients had DHL while 6113 had non-DHL. Second line chemotherapy was administered to 147 DHL patients and 1517 non-DHL. 1393 were excluded, including 934 with unknown DHL/THL status. Approximately 47% received salvage intent chemotherapy in the DHL subgroup, of which 19% patients eventually received ASCT, while 34% received salvage intent chemotherapy in the non-DHL/THL group with 32% receiving ASCT. DHL/THL status negatively influenced median rwOS for patients who underwent ASCT in the second-line while it was associated with numerically inferior but without statistically significant rwOS among patients that underwent CAR Tcell therapy on multivariable analysis.

CONCLUSION

rwOS of relapsed DHL/THL is inferior to non-DHL/THL. Fewer patients with DHL/THL were able to proceed with ASCT after salvage chemotherapy compared to non-DHL/THL. ASCT as second-line therapy for relapsed DHL/THL had worse rwOS than for non-DHL/THL, consistent with the natural history of DHL/THL. This difference was not seen for CAR Tcell therapy, which combined with promising results from clinical trials, suggests a greater role for CAR T-cell therapy in relapsed/refractory DHL.

Role of CD19 Chimeric Antigen Receptor T Cells in Second-Line Large B Cell Lymphoma: Lessons from Phase 3 Trials. An Expert Panel Opinion from the American Society for Transplantation and Cellular Therapy

Since 2017, 3 CD19-directed chimeric antigen receptor (CAR) T cell therapies-axicabtagene ciloleucel, tisagenlecleucel, and lisocabtagene maraleucel-have been approved for relapsed/refractory aggressive diffuse large B cell lymphoma after 2 lines of therapy. Recently, 3 prospective phase 3 randomized clinical trials were conducted to define the optimal second-line treatment by comparing each of the CAR T cell products to the current standard of care: ZUMA-7 for axicabtagene ciloleucel, BELINDA for tisagenlecleucel, and TRANSFORM for lisocabtagene maraleucel. These 3 studies, although largely addressing the same question, had different outcomes, with ZUMA-7 and TRANSFORM demonstrating significant improvement with CD19 CAR T cells in second-line therapy compared with standard of care but BELINDA not showing any benefit. The US Food and Drug Administration has now approved axicabtagene ciloleucel and lisocabtagene maraleucel for LBCL that is refractory to first-line chemoimmunotherapy or relapse occurring within 12 months of first-line chemoimmunotherapy. Following the reporting of these practice changing studies, here a group of experts convened by the American Society for Transplantation and Cellular Therapy provides a comprehensive review of the 3 studies, emphasizing potential differences, and shares perspectives on what these results mean to clinical practice in this new era of treatment of B cell lymphomas.

Axicabtagene Ciloleucel as Second-Line Therapy for Large B-Cell Lymphoma

BACKGROUND

The prognosis of patients with early relapsed or refractory large B-cell lymphoma after the receipt of first-line chemoimmunotherapy is poor.

METHODS

In this international, phase 3 trial, we randomly assigned, in a 1:1 ratio, patients with large B-cell lymphoma that was refractory to or had relapsed no more than 12 months after first-line chemoimmunotherapy to receive axicabtagene ciloleucel (axi-cel, an autologous anti-CD19 chimeric antigen receptor T-cell therapy) or standard care (two or three cycles of investigator-selected, protocol-defined chemoimmunotherapy, followed by high-dose chemotherapy with autologous stem-cell transplantation in patients with a response to the chemoimmunotherapy). The primary end point was event-free survival according to blinded central review. Key secondary end points were response and overall survival. Safety was also assessed.

RESULTS

A total of 180 patients were randomly assigned to receive axi-cel and 179 to receive standard care. The primary end-point analysis of event-free survival showed that axi-cel therapy was superior to standard care. At a median follow-up of 24.9 months, the median event-free survival was 8.3 months in the axi-cel group and 2.0 months in the standard-care group, and the 24-month event-free survival was 41% and 16%, respectively (hazard ratio for event or death, 0.40; 95% confidence interval, 0.31 to 0.51; P<0.001). A response occurred in 83% of the patients in the axi-cel group and in 50% of those in the standard-care group (with a complete response in 65% and 32%, respectively). In an interim analysis, the estimated overall survival at 2 years was 61% in the axi-cel group and 52% in the standard-care group. Adverse events of grade 3 or higher occurred in 91% of the patients who received axi-cel and in 83% of those who received standard care. Among patients who received axi-cel, grade 3 or higher cytokine release syndrome occurred in 6% and grade 3 or higher neurologic events in 21%. No deaths related to cytokine release syndrome or neurologic events occurred.

CONCLUSIONS

Axi-cel therapy led to significant improvements, as compared with standard care, in event-free survival and response, with the expected level of high-grade toxic effects. (Funded by Kite; ZUMA-7 ClinicalTrials.gov number, NCT03391466.).