CXCR4-targeted Theranostics in Hematooncology: Opportunities and Challenges

C-X-C motif chemokine receptor 4 (CXCR4) is overexpressed in a multitude of cancers, including neoplasms of hematopoietic origin. This feature can be leveraged by a theranostic approach, which provides a read-out of the actual CXCR4 expression in vivo, followed by CXCR4-targeted radioligand therapy (RLT) exerting anti-cancer as well as myeloablative efficacy. In a recent meeting of hematooncology and nuclear medicine specialists, statements on the current clinical practice and future perspectives of this innovative concept were proposed and summarized in this opinion article. Experts concluded that i) CXCR4-directed [68Ga]Ga-PentixaFor PET/CT has the potential to improve imaging for patients with marginal zone lymphoma; ii) CXCR4-targeted RLT exerts anti-lymphoma efficacy and myeloablative effects in patients with advanced, treatment-refractory T-cell lymphomas; iii) prospective trials with CXCR4-based imaging and theranostics are warranted.

Molecular assessment of intratumoral immune cell subsets and potential mechanisms of resistance to odronextamab, a CD20×CD3 bispecific antibody, in patients with relapsed/refractory B-cell non-Hodgkin lymphoma

BACKGROUND

Patients with relapsed/refractory B-cell non-Hodgkin lymphoma (R/R B-NHL) have a significant need for effective treatment options. Odronextamab is an Fc-silenced, human, CD20×CD3 bispecific antibody that targets CD20-expressing cells via T-cell-mediated cytotoxicity independent of T-cell/major histocompatibility complex interaction. Phase I results in patients with R/R B-NHL demonstrated that odronextamab monotherapy could achieve deep and durable responses with a generally manageable safety profile (ELM-1; NCT02290951). As part of a biomarker analysis of the same study, we investigated potential biomarkers and mechanisms of resistance to odronextamab.

METHODS

Patients with R/R B-NHL enrolled in ELM-1 received one time per week doses of intravenous odronextamab for 4×21 day cycles, then doses every 2 weeks thereafter. Patient tumor biopsies were obtained at baseline, on-treatment, and at progression. Immune cell markers were analyzed by immunohistochemistry, flow cytometry, single-cell RNA sequencing, and whole genome sequencing.

RESULTS

Baseline tumor biopsies showed that almost all patients had high proportions of B cells that expressed the CD20 target antigen, whereas expression of other B-cell surface antigens (CD19, CD22, CD79b) was more variable. Responses to odronextamab in patients with diffuse large B-cell lymphoma were not related to the relative level of baseline CD20 expression, cell of origin, or high-risk molecular subtype. A potential link was observed between greater tumor programmed cell death-ligand 1 expression and increased likelihood of response to odronextamab. Similarly, a trend was observed between clinical response and increased levels of CD8 T cells and regulatory T cells at baseline. We also identified an on-treatment pharmacodynamic shift in intratumoral immune cell subsets. Finally, loss of CD20 expression through inactivating gene mutations was identified as a potential mechanism of resistance in patients who were treated with odronextamab until progression, as highlighted in two detailed patient cases reported here.

CONCLUSIONS

This biomarker analysis expands on clinical findings of odronextamab in patients with R/R B-NHL, providing verification of the suitability of CD20 as a therapeutic target, as well as evidence for potential mechanisms of action and resistance.

Sequential antigen loss and branching evolution in lymphoma after CD19- and CD20-targeted T-cell-redirecting therapy

ABSTRACT

CD19 chimeric antigen receptor (CAR) T cells and CD20 targeting T-cell-engaging bispecific antibodies (bispecs) have been approved in B-cell non-Hodgkin lymphoma lately, heralding a new clinical setting in which patients are treated with both approaches, sequentially. The aim of our study was to investigate the selective pressure of CD19- and CD20-directed therapy on the clonal architecture in lymphoma. Using a broad analytical pipeline on 28 longitudinally collected specimen from 7 patients, we identified truncating mutations in the gene encoding CD20 conferring antigen loss in 80% of patients relapsing from CD20 bispecs. Pronounced T-cell exhaustion was identified in cases with progressive disease and retained CD20 expression. We also confirmed CD19 loss after CAR T-cell therapy and reported the case of sequential CD19 and CD20 loss. We observed branching evolution with re-emergence of CD20+ subclones at later time points and spatial heterogeneity for CD20 expression in response to targeted therapy. Our results highlight immunotherapy as not only an evolutionary bottleneck selecting for antigen loss variants but also complex evolutionary pathways underlying disease progression from these novel therapies.

Chemokine receptor-targeted PET/CT provides superior diagnostic performance in newly diagnosed marginal zone lymphoma patients: a head-to-head comparison with [18F]FDG

BACKGROUND

In patients with marginal zone lymphoma (MZL), [18F]FDG PET/CT provided inconsistent diagnostic accuracy. C-X-C motif chemokine receptor 4 (CXCR4) is overexpressed in MZL and thus, may emerge as novel theranostic target. We aimed to evaluate the diagnostic performance of CXCR4-targeting [68Ga]Ga-PentixaFor when compared to [18F]FDG PET/CT in MZL.

METHODS

Thirty-two untreated MZL patients (nodal, n = 17; extranodal, n = 13; splenic, n = 2) received [68Ga]Ga-PentixaFor and [18F]FDG PET/CT within median 2 days. We performed a visual and quantitative analysis of the total lymphoma volume by measuring maximum/peak standardized uptake values (SUVmax/peak), and calculating target-to-background ratios (TBR, defined as lesion-based SUVpeak divided by SUVmean from blood pool). Visual comparisons for both radiotracers were carried out for all target lesions (TL), and quantitative analysis of concordant TL evident on both scans. Last, MZL subtype analyses were also conducted.

RESULTS

On a patient-based level, [68Ga]Ga-PentixaFor identified MZL manifestations in 32 (100%) subjects (vs. [18F]FDG, 25/32 [78.1%]). Of the 256 identified TL, 127/256 (49.6%) manifestations were evident only on CXCR4-directed imaging, while only 7/256 (2.7%) were identified on [18F]FDG but missed by [68Ga]Ga-PentixaFor. In the remaining 122/256 (47.7%) concordant TL, [68Ga]Ga-PentixaFor consistently provided increased metrics when compared to [18F]FDG: SUVmax, 10.3 (range, 2.53-37.2) vs. 5.72 (2.32-37.0); SUVpeak, 6.23 (1.58-25.7) vs. 3.87 (1.54-27.7); P < 0.01, respectively. Concordant TL TBR on [68Ga]Ga-PentixaFor (median, 3.85; range, 1.05-16.0) was also approximately 1.8-fold higher relative to [18F]FDG (median, 2.08; range, 0.81-28.8; P < 0.01). Those findings on image contrast, however, were driven by nodal MZL (P < 0.01), and just missed significance for extranodal MZL (P = 0.06).

CONCLUSIONS

In newly diagnosed MZL patients, [68Ga]Ga-PentixaFor identified more sites of disease when compared to [18F]FDG, irrespective of MZL subtype. Quantitative PET parameters including TBR were also higher on [68Ga]Ga-PentixaFor PET/CT, suggesting improved diagnostic read-out using chemokine receptor-targeted imaging.

Follow-up of the GHSG HD16 trial of PET-guided treatment in early-stage favorable Hodgkin lymphoma

The primary analysis of the GHSG HD16 trial indicated a significant loss of tumor control with PET-guided omission of radiotherapy (RT) in patients with early-stage favorable Hodgkin lymphoma (HL). This analysis reports long-term outcomes. Overall, 1150 patients aged 18-75 years with newly diagnosed early-stage favorable HL were randomized between standard combined-modality treatment (CMT) (2x ABVD followed by PET/CT [PET-2] and 20 Gy involved-field RT) and PET-2-guided treatment omitting RT in case of PET-2 negativity (Deauville score [DS] < 3). The study aimed at excluding inferiority of PET-2-guided treatment and assessing the prognostic impact of PET-2 in patients receiving CMT. At a median follow-up of 64 months, PET-2-negative patients had a 5-year progression-free survival (PFS) of 94.2% after CMT (n = 328) and 86.7% after ABVD alone (n = 300; HR = 2.05 [1.20-3.51]; p = 0.0072). 5-year OS was 98.3% and 98.8%, respectively (p = 0.14); 4/12 documented deaths were caused by second primary malignancies and only one by HL. Among patients assigned to CMT, 5-year PFS was better in PET-2-negative (n = 353; 94.0%) than in PET-2-positive patients (n = 340; 90.3%; p = 0.012). The difference was more pronounced when using DS4 as cut-off (DS 1-3: n = 571; 94.0% vs. DS ≥ 4: n = 122; 83.6%; p < 0.0001). Taken together, CMT should be considered standard treatment for early-stage favorable HL irrespective of the PET-2-result.

Chemokine Receptor PET/CT Provides Relevant Staging and Management Changes in Marginal Zone Lymphoma

Because of gastral and extranodal manifestations, guideline-compatible diagnostic work-up of marginal zone lymphoma is challenging. We aimed to determine the diagnostic performance of C-X-C motif chemokine receptor 4 (CXCR4)-directed PET/CT compared with routine diagnostics, along with PET/CT-based retrospective changes in therapeutic management. The predictive potential of the PET signal was also investigated, and the number of patients eligible for CXCR4-directed radioligand therapy in a theranostic setting was determined. Methods: For this study, 100 marginal zone lymphoma patients underwent CXCR4-directed PET/CT. We compared staging results and treatment decisions from molecular imaging with respective results from guideline-compatible work-up (CT, esophagogastroduodenoscopy, and bone marrow-derived biopsy). Prognostic performance of the in vivo CXCR4 PET signal for progression-free survival (PFS) was evaluated (using log-rank test and Kaplan-Meier curves). Results: Relative to CT, CXCR4-directed imaging led to Ann Arbor (AA) staging changes for 27 of 100 patients (27.0%). Among those, clinically relevant upstaging from AA I or AA II to AA III or AA IV was observed for 23 patients (85.2%), along with respective changes in therapeutic management (escalation, 6/23 [26.1%]; deescalation, 17/23 [73.9%]). CXCR4 PET/CT yielded diagnostic accuracy of 94.0% relative to esophagogastroduodenoscopy and 76.8% relative to bone marrow-derived biopsy. An increased CXCR4 PET signal was linked to shorter PFS (707 d vs. median PFS not reached; hazard ratio, 3.18; 95% CI, 1.37-7.35; P = 0.01). CXCR4-directed radioligand therapy would have been feasible for 18 of 100 patients (18.0%). Conclusion: Relative to CT, CXCR4-directed PET/CT led to AA changes for 27 of 100 patients. Chemokine receptor PET/CT may improve current diagnostic algorithms and influence management relative to CT alone, potentially obviating some biopsies.

Enolase 1 of Candida albicans binds human CD4+ T cells and modulates naïve and memory responses

To obtain a better understanding of the biology behind life-threatening fungal infections caused by Candida albicans, we recently conducted an in silico screening for fungal and host protein interaction partners. We report here that the extracellular domain of human CD4 binds to the moonlighting protein enolase 1 (Eno1) of C. albicans as predicted bioinformatically. By using different anti-CD4 monoclonal antibodies, we determined that C. albicans Eno1 (CaEno1) primarily binds to the extracellular domain 3 of CD4. Functionally, we observed that CaEno1 binding to CD4 activated lymphocyte-specific protein tyrosine kinase (LCK), which was also the case for anti-CD4 monoclonal antibodies tested in parallel. CaEno1 binding to naïve human CD4+ T cells skewed cytokine secretion toward a Th2 profile indicative of poor fungal control. Moreover, CaEno1 inhibited human memory CD4+ T-cell recall responses. Therapeutically, CD4+ T cells transduced with a p41/Crf1-specific T-cell receptor developed for adoptive T-cell therapy were not inhibited by CaEno1 in vitro. Together, the interaction of human CD4+ T cells with CaEno1 modulated host CD4+ T-cell responses in favor of the fungus. Thus, CaEno1 mediates not only immune evasion through its interference with complement regulators but also through the direct modulation of CD4+ T-cell responses.

Interim PET-guided treatment for early-stage NLPHL: a subgroup analysis of the randomized GHSG HD16 and HD17 studies

The optimal first-line treatment for nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) diagnosed in early stages is largely undefined. We, therefore, analyzed 100 NLPHL patients treated in the randomized HD16 (early-stage favorable; n = 85) and HD17 (early-stage unfavorable; n = 15) studies. These studies investigated the omission of consolidation radiotherapy (RT) in patients with a negative interim positron emission tomography (iPET) (ie, Deauville score <3) after chemotherapy (HD16: 2× doxorubicin, bleomycin, vinblastine, and dacarbazine [ABVD]; HD17: 2× escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone [BEACOPP] plus 2× ABVD). Patients with NLPHL treated in the HD16 and HD17 studies had 5-year progression-free survival (PFS) rates of 90.3% and 92.9%, respectively. Thus, the 5-year PFS did not differ significantly from that of patients with classical Hodgkin lymphoma treated within the same studies (HD16: P = .88; HD17: P = .50). Patients with early-stage favorable NLPHL who had a negative iPET after 2× ABVD and did not undergo consolidation RT tended to have a worse 5-year PFS than patients with a negative iPET who received consolidation RT (83% vs 100%; P = .05). There were 10 cases of NLPHL recurrence. However, no NLPHL patient died during follow-up. Hence, the 5-year overall survival rate was 100%. Taken together, contemporary Hodgkin lymphoma-directed treatment approaches result in excellent outcomes for patients with newly diagnosed early-stage NLPHL and, thus, represent valid treatment options. In early-stage favorable NLPHL, consolidation RT appears necessary after 2× ABVD to achieve the optimal disease control irrespective of the iPET result.

Impact of prior therapies and subsequent transplantation on outcomes in adult patients with relapsed or refractory B-cell acute lymphoblastic leukemia treated with brexucabtagene autoleucel in ZUMA-3

BACKGROUND

Brexucabtagene autoleucel (brexu-cel) is an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved in the USA for adults with relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL) and in the European Union for patients ≥26 years with R/R B-ALL. After 2 years of follow-up in ZUMA-3, the overall complete remission (CR) rate (CR+CR with incomplete hematological recovery (CRi)) was 73%, and the median overall survival (OS) was 25.4 months in 78 Phase 1 and 2 patients with R/R B-ALL who received the pivotal dose of brexu-cel. Outcomes by prior therapies and subsequent allogeneic stem cell transplantation (alloSCT) are reported.

METHODS

Eligible adults had R/R B-ALL and received one infusion of brexu-cel (1×10⁶ CAR T cells/kg) following conditioning chemotherapy. The primary endpoint was the CR/CRi rate per central review. Post hoc subgroup analyses were exploratory with descriptive statistics provided.

RESULTS

Phase 1 and 2 patients (N=78) were included with median follow-up of 29.7 months (range, 20.7-58.3). High CR/CRi rates were observed across all prior therapy subgroups examined: 1 prior line of therapy (87%, n=15) and ≥2 prior lines (70%, n=63); prior blinatumomab (63%, n=38) and no prior blinatumomab (83%, n=40); prior inotuzumab (59%, n=17) and no prior inotuzumab (77%, n=61); and prior alloSCT (76%, n=29) and no prior alloSCT (71%, n=49). The frequency of Grade ≥3 cytokine release syndrome, neurological events, and treatment-related Grade 5 adverse events were largely similar among prior therapy subgroups.Median duration of remission (DOR) in responders with (n=14) and without (n=43) subsequent alloSCT was 44.2 (95% CI, 8.1 to not estimable (NE)) and 18.6 months (95% CI, 9.4 to NE); median OS was 47.0 months (95% CI, 10.2 to NE) and not reached (95% CI, 23.2 to NE), respectively. Median DOR and OS were not reached in responders without prior or subsequent alloSCT (n=22).

CONCLUSIONS

In ZUMA-3, adults with R/R B-ALL benefited from brexu-cel, regardless of prior therapies and subsequent alloSCT status, though survival appeared better in patients without certain prior therapies and in earlier lines of therapy. Additional studies are needed to determine the impact prior therapies and subsequent alloSCT have on outcomes of patients who receive brexu-cel.

Lymphoma-Sink Effect in Marginal Zone Lymphoma Based on CXCR4-Targeted Molecular Imaging

PURPOSE

Recent studies investigating a tumor-sink effect in solid tumors reported on decreasing uptake in normal organs in patients with higher tumor burden. This phenomenon, however, has not been evaluated yet for theranostic radiotracers applied to hematological neoplasms. As such, we aimed to determine a potential "lymphoma-sink effect" in patients with marginal zone lymphoma (MZL) imaged with C-X-C motif chemokine receptor (CXCR) 4-directed PET/CTs.

PROCEDURES

We retrospectively analyzed 73 patients with MZL who underwent CXCR4-directed [⁶⁸Ga]Ga-PentixaFor PET/CT. Normal unaffected organ uptake (heart, liver, spleen, bone marrow, kidneys) was quantified using volumes of interests (VOIs) and mean standardized uptake values (SUV_mean) were derived. MZL manifestations were also segmented to determine the maximum and peak standardized uptake values SUV (SUV_max/peak) and volumetric parameters, including lymphoma volume (LV), and fractional lymphoma activity (FLA, defined as LV*SUV_mean of lymphoma burden). This approach resulted in 666 VOIs to capture the entire MZL manifestation load. We used Spearman's rank correlations to determine associations between organ uptake and CXCR4-expressing lymphoma lesions.

RESULTS

We recorded the following median SUV_mean in normal organs: heart, 1.82 (range, 0.78-4.11); liver, 1.35 (range, 0.72-2.99); bone marrow, 2.36 (range, 1.12-4.83); kidneys, 3.04 (range, 2.01-6.37); spleen, 5.79 (range, 2.07-10.5). No relevant associations between organ radiotracer uptake and MZL manifestation were observed, neither for SUV_max (ρ ≤ 0.21, P ≥ 0.07), SUV_peak (ρ ≤ 0.20, P ≥ 0.09), LV (ρ ≤ 0.13, P ≥ 0.27), nor FLA (ρ ≤ 0.15, P ≥ 0.33).

CONCLUSIONS

Investigating a lymphoma-sink effect in patients with hematological neoplasms, we observed no relevant associations between lymphoma burden and uptake in normal organs. Those observations may have therapeutic implications, e.g., for "cold" SDF1-pathway disrupting or "hot," CXCR4-directed radiolabeled drugs, as with higher lymphoma load, normal organ uptake seems to remain stable.

General condition and comorbidity of long-term survivors of adult acute lymphoblastic leukemia

Cure rates in adult acute lymphoblastic leukemia (ALL) improved using pediatric-based chemotherapy and stem cell transplantation (SCT). However, limited data on health condition of cured adults are available whereas pediatric data cannot be transferred. The GMALL analyzed the health status in survivors of adult ALL retrospectively. Physicians answered a questionnaire on general condition (ECOG status) and comorbidity or syndrome occurrence observed after treatment. 538 patients with a median age of 29 (15-64) years at diagnosis were analyzed, median follow-up was seven (3-24) years. 31% had received SCT. ECOG status was 0-1 in 94%, 34% had not developed significant comorbidities. Most frequent comorbidities involved the neurologic system (27%), endocrine system (20%), skin (18%), Graft-versus-Host-Disease (15%), cardiac system (13%), fatigue (13%). SCT impacted ECOG status and comorbidity occurrence significantly. ECOG 0-1 was observed in 86% of SCT and 98% of non-SCT patients (p.

Virus variant-specific clinical performance of SARS coronavirus two rapid antigen tests in point-of-care use, from November 2020 to January 2022

OBJECTIVES

Antigen rapid diagnostic tests (RDTs) for SARS coronavirus 2 (SARS-CoV-2) are quick, widely available, and inexpensive. Consequently, RDTs have been established as an alternative and additional diagnostic strategy to quantitative reverse transcription polymerase chain reaction (RT-qPCR). However, reliable clinical and large-scale performance data specific to a SARS-CoV-2 virus variant of concern (VOC) are limited, especially for the Omicron VOC. The aim of this study was to compare RDT performance among different VOCs.

METHODS

This single-centre prospective performance assessment compared RDTs from three manufacturers (NADAL, Panbio, MEDsan) with RT-qPCR including deduced standardized viral load from oropharyngeal swabs for detection of SARS-CoV-2 in a clinical point-of-care setting from November 2020 to January 2022.

RESULTS

Among 35 479 RDT/RT-qPCR tandems taken from 26 940 individuals, 164 of the 426 SARS-CoV-2 positive samples tested true positive with an RDT corresponding to an RDT sensitivity of 38.50% (95% CI, 34.00-43.20%), with an overall specificity of 99.67% (95% CI, 99.60-99.72%). RDT sensitivity depended on viral load, with decreasing sensitivity accompanied by descending viral load. VOC-dependent sensitivity assessment showed a sensitivity of 42.86% (95% CI, 32.82-53.52%) for the wild-type SARS-CoV-2, 43.42% (95% CI, 32.86-54.61%) for the Alpha VOC, 37.67% (95% CI, 30.22-45.75%) for the Delta VOC, and 33.67% (95% CI, 25.09-43.49%) for the Omicron VOC. Sensitivity in samples with high viral loads of ≥10⁶ SARS-CoV-2 RNA copies per mL was significantly lower in the Omicron VOC (50.00%; 95% CI, 36.12-63.88%) than in the wild-type SARS-CoV-2 (79.31%; 95% CI, 61.61-90.15%; p 0.015).

DISCUSSION

RDT sensitivity for detection of the Omicron VOC is reduced in individuals infected with a high viral load, which curtails the effectiveness of RDTs. This aspect furthert: limits the use of RDTs, although RDTs are still an irreplaceable diagnostic tool for rapid, economic point-of-care and extensive SARS-CoV-2 screening.

Three-Year Follow-Up of KTE-X19 in Patients With Relapsed/Refractory Mantle Cell Lymphoma, Including High-Risk Subgroups, in the ZUMA-2 Study

PURPOSE

Brexucabtagene autoleucel (KTE-X19) autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy is approved for the treatment of relapsed/refractory mantle cell lymphoma (MCL). Outcomes after a 3-year follow-up in the pivotal ZUMA-2 study of KTE-X19 in relapsed/refractory MCL are reported, including for subgroups by prior therapy (bendamustine and type of Bruton tyrosine kinase inhibitor [BTKi]) or high-risk characteristics.

METHODS

Patients with relapsed/refractory MCL (one to five prior therapies, including prior BTKi exposure) received a single infusion of KTE-X19 (2 × 10⁶ CAR T cells/kg).

RESULTS

After a median follow-up of 35.6 months, the objective response rate among all 68 treated patients was 91% (95% CI, 81.8 to 96.7) with 68% complete responses (95% CI, 55.2 to 78.5); medians for duration of response, progression-free survival, and overall survival were 28.2 months (95% CI, 13.5 to 47.1), 25.8 months (95% CI, 9.6 to 47.6), and 46.6 months (95% CI, 24.9 to not estimable), respectively. Post hoc analyses showed that objective response rates and ongoing response rates were consistent among prespecified subgroups by prior BTKi exposure or high-risk characteristics. In an exploratory analysis, patients with prior bendamustine benefited from KTE-X19, but showed a trend toward attenuated T-cell functionality, with more impact of bendamustine given within 6 versus 12 months of leukapheresis. Late-onset toxicities were infrequent; only 3% of treatment-emergent adverse events of interest in ZUMA-2 occurred during this longer follow-up period. Translational assessments revealed associations with long-term benefits of KTE-X19 including high-peak CAR T-cell expansion in responders and the predictive value of minimal residual disease for relapse.

CONCLUSION

These data, representing the longest follow-up of CAR T-cell therapy in patients with MCL to date, suggest that KTE-X19 induced durable long-term responses with manageable safety in patients with relapsed/refractory MCL and may also benefit those with high-risk characteristics.

Two-year follow-up of KTE-X19 in patients with relapsed or refractory adult B-cell acute lymphoblastic leukemia in ZUMA-3 and its contextualization with SCHOLAR-3, an external historical control study

BACKGROUND

Brexucabtagene autoleucel (KTE-X19) is an autologous anti-CD19 CAR T-cell therapy approved in the USA to treat adult patients with relapsed or refractory B-precursor acute lymphoblastic leukemia (R/R B-ALL) based on ZUMA-3 study results. We report updated ZUMA-3 outcomes with longer follow-up and an extended data set along with contextualization of outcomes to historical standard of care.

METHODS

Adults with R/R B-ALL received a single infusion of KTE-X19 (1 × 10⁶ CAR T cells/kg). Long-term post hoc subgroup assessments of ZUMA-3 were conducted. Outcomes from matched patients between historical clinical trials and ZUMA-3 patients were assessed in the retrospective historical control study SCHOLAR-3.

RESULTS

After 26.8-months median follow-up, the overall complete remission (CR) rate (CR + CR with incomplete hematological recovery) among treated patients (N = 55) in phase 2 was 71% (56% CR rate); medians for duration of remission and overall survival (OS) were 14.6 and 25.4 months, respectively. Most patients responded to KTE-X19 regardless of age or baseline bone marrow blast percentage, but less so in patients with > 75% blasts. No new safety signals were observed. Similar outcomes were observed in a pooled analysis of phase 1 and 2 patients (N = 78). In SCHOLAR-3, the median OS for treated patients from ZUMA-3 (N = 49) and matched historical controls (N = 40) was 25.4 and 5.5 months, respectively.

CONCLUSIONS

These data, representing the longest follow-up of CAR T-cell therapy in a multicenter study of adult R/R B-ALL, suggest that KTE-X19 provides a clinically meaningful survival benefit with manageable toxicity in this population.

TRIAL REGISTRATION

NCT02614066.

Two-year follow-up of KTE-X19, an anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, in adult patients (Pts) with relapsed/refractory B-cell acute lymphoblastic leukemia (R/R B-ALL) in ZUMA-3

7010

Background: Brexucabtagene autoleucel (KTE-X19) is an autologous anti-CD19 CAR T-cell therapy approved in the US to treat adult R/R B-ALL based on the ZUMA-3 study. The overall complete remission (CR) rate (CR + CR with incomplete hematologic recovery [CRi]) was 71% (95% CI, 57-82) after 16.4 mo median follow-up (N = 55; Shah et al. Lancet 2021). Here, we report updated outcomes with longer follow-up in these pts and in a larger pooled analysis of Phase (Ph) 1 and 2 pts who received the pivotal dose of KTE-X19. Methods: Eligible adults (≥18 years) had R/R B-ALL and received a single infusion of KTE-X19 at the pivotal dose (1×106 CAR T cells/kg) following leukapheresis and conditioning chemotherapy. The primary endpoint was CR/CRi rate by central review. Results: As of 23 July 2021, median follow-up was 26.8 mo (range, 20.7-32.6) for treated Ph 2 pts (N = 55). The CR/CRi rate per central review was 71% (95% CI, 57-82; 56% CR; 15% CRi). Eleven pts (20%; 8 CR and 2 CRi) proceeded to subsequent allogeneic stem cell transplant (alloSCT). Median duration of remission (DOR) censored at subsequent alloSCT was 14.6 mo (9.4-not estimable [NE]); not censored: 18.6 mo (9.6-NE); 6/39 responders (15%) had ongoing responses at data cutoff. Median (95% CI) relapse-free survival (RFS) was 11.6 mo (2.7-20.5) censored at subsequent alloSCT and 11.7 mo (2.8-20.5) not censored at subsequent alloSCT; 18-mo RFS rates (95% CI) were 35% (20.5-50.6) and 42% (28.0-55.0), respectively. Median (95% CI) overall survival (OS) was 25.4 mo (16.2-NE) among all KTE-X19-treated pts and not reached (25.4-NE) in pts with CR (n = 31). For Ph 1/2 pts (N = 78) who received the pivotal KTE-X19 dose (median follow-up: 29.7 mo; range 20.7-58.3), the CR/CRi rate by independent review was 73% (95% CI, 62-82). Medians (95% CI) for DOR, RFS, and OS were 18.6 mo (9.6-NE), 11.7 mo (6.1-20.5), and 25.4 mo (16.2-NE), respectively. A subgroup analysis revealed that in pts aged 18-39 (n = 36), 40-59 (n = 27), and ≥60 (n = 15) years, the CR/CRi rates (95% CI) were 69% (52-84), 70% (50-86), and 87% (60-98); 24-mo OS rates (95% CI) were 48% (30-64), 54% (33-71), and 57% (28-78), respectively. In pts with pre-KTE-X19 infusion marrow blast percentages > 25 to ≤50 (n = 12), > 50 to ≤75 (n = 14), and > 75 to 100 (n = 30), CR/CRi rates (95% CI) were 83% (52-98), 86% (57-98), and 57% (37-75); 24-mo OS rates (95% CI) were 58% (27-80), 55% (26-77) and 37% (19-55), respectively. There were no new safety signals; the proportion of treated Ph 2 pts with Gr ≥3 treatment emergent adverse events was unchanged since prior data cutoff. One pt had an ongoing neurologic event of Gr 1 finger numbness. Conclusions: With longer follow-up and an expanded data set by independent review, outcomes remain durable in adults with R/R B-ALL, most of whom were heavily pretreated, with median OS not yet reached in pts with CR. Long-term safety was favorable. Clinical trial information: NCT02614066.

Odronextamab, a human CD20×CD3 bispecific antibody in patients with CD20-positive B-cell malignancies (ELM-1): results from the relapsed or refractory non-Hodgkin lymphoma cohort in a single-arm, multicentre, phase 1 trial

BACKGROUND

Odronextamab is a hinge-stabilised, fully human IgG4-based CD20 × CD3 bispecific antibody that binds CD3 on T cells and CD20 on B cells. We aimed to evaluate the safety and antitumour activity of odronextamab in patients with relapsed or refractory B-cell non-Hodgkin lymphoma.

METHODS

This single-arm, multicentre, phase 1, dose-escalation and dose-expansion (ELM-1) trial was conducted at ten academic sites across the USA and Germany. Patients aged 18 years or older with CD20-positive relapsed or refractory B-cell malignancies who previously received CD20-directed antibody therapy and who had at least one measurable lesion, and an ECOG performance status of 0 or 1 were included. Patients received intravenous odronextamab, according to a step-up dosing schedule in cycle 1, followed by treatment once per week at target doses ranging from 0·1 mg to 320 mg during cycles 2-4 (each cycle was 21 days). After cycle 4, maintenance treatment occurred every 2 weeks until disease progression or unacceptable toxicity. The primary endpoint of safety was assessed by the incidence of adverse events and dose-limiting toxicities to determine the maximum tolerated dose or phase 2 dose of odronextamab, or both. Preliminary antitumour activity, as measured by objective response rate, was a secondary endpoint. This study is registered with ClinicalTrials.gov, NCT02290951.

FINDINGS

From Feb 4, 2015, to Sept 25, 2021, 145 heavily pretreated patients (median of 3 (IQR 2-5] previous therapies) were enrolled (94 to the dose-escalation and 51 to the dose-expansion part of the study). The median age of patients was 67·0 years (IQR 57·0-73·0); 101 (70%) were male and 44 (30%) were female; most participants were White (119 [82%]) and not Hispanic or Latino (132 [91%]). 42 (29%) patients received previous CAR T therapy and 119 (82%) were refractory to the last line of therapy. Median duration of follow-up was 4·2 months (IQR 1·5-11·5). During dose escalation, odronextamab was administered up to the maximum dose of 320 mg once per week and no dose-limiting toxicities were observed. The recommended dose for expansion in patients with follicular lymphoma grade 1-3a was 80 mg and was 160 mg for patients with diffuse large B-cell lymphoma. Cytokine release syndrome and neurological treatment-emergent adverse events were predominantly low grade and did not result in treatment discontinuation. The most common grade 3 or worse treatment-emergent adverse events were anaemia (36 [25%]), lymphopenia (28 [19%]), hypophosphataemia (27 [19%]), neutropenia (27 [19%]), and thrombocytopenia (20 [14%]). Serious treatment-emergent adverse events occurred in 89 (61%) of 145 patients; the most frequent were cytokine release syndrome (41 [28%]), pyrexia (11 [8%]), pneumonia (nine [6%]), and infusion-related reaction (six [4%]). Four deaths were considered related to treatment (gastric perforation in a patient with gastric involvement by lymphoma, lung infection, pneumonia, and tumour-lysis syndrome). Objective response rate was 51% (95% CI 42-59; 72 of 142). In patients with follicular lymphoma who received odronextamab doses of 5 mg or higher, the objective response rate was 91% (95% CI 75-98; 29 of 32) and the complete response rate was 72% (95% CI 53-86; 23 of 32). In patients with diffuse large B-cell lymphoma without previous CAR T-cell therapy who received doses of 80 mg or higher, the objective response rate was 53% (eight of 15) and all responses were complete responses. In patients with diffuse large B-cell lymphoma who had previous CAR T-cell therapy and received doses of 80 mg or higher, the objective response rate was 33% (ten of 30) and complete response rate was 27% (eight of 30).

INTERPRETATION

Odronextamab monotherapy showed a manageable safety profile and encouraging preliminary activity, including durable responses in heavily pretreated patients with B-cell non-Hodgkin lymphoma, supporting further clinical investigation in phase 2 and 3 trials.

FUNDING

Regeneron Pharmaceuticals.

Reinduction therapy with everolimus in combination with dexamethasone, high-dose cytarabin and cisplatinum in patients with relapsed or refractory classical Hodgkin lymphoma: an experimental phase I/II multicentre trial of the German Hodgkin Study Group (GHSG HD-R3i)

Reinduction chemotherapy followed by high-dose chemotherapy and autologous stem cell transplant (HDCT + ASCT) is second-line standard of care for transplant-eligible patients with relapsed/refractory classical Hodgkin lymphoma (r/r cHL) but has a high failure rate. Because response to reinduction is predictive of the outcome after HDCT + ASCT, we aimed to improve the standard dexamethasone, high-dose cytarabine and cisplatinum (DHAP) reinduction regimen by addition of the oral mammalian target of rapamycin inhibitor everolimus (everDHAP). Transplant-eligible patients aged 18-60 years with histologically confirmed r/r cHL were included in this experimental phase I/II trial. Everolimus (10 mg/day, determined in phase-I-part) was administered on day 0-13 of each DHAP cycle. From July 2014 to March 2018, 50 patients were recruited to the phase II everDHAP group; two were not evaluable, three discontinued due to toxicity. Randomization to a placebo group stopped in October 2015 due to poor recruitment after nine patients. The primary end-point of computed tomography (CT)-based complete remission (CR) after two cycles of everDHAP was expected to be ≥40%. With a CT-based CR rate of 27% (n = 12/45) after two cycles of everDHAP the trial did not meet the primary end-point. Adding everolimus to DHAP is thus feasible; however, the everDHAP regimen failed to show an improved efficacy.

Earlier corticosteroid use for adverse event management in patients receiving axicabtagene ciloleucel for large B-cell lymphoma

Axicabtagene ciloleucel (axi‐cel) is an autologous anti‐CD19 chimeric antigen receptor (CAR) T‐cell therapy approved for relapsed or refractory large B‐cell lymphoma (R/R LBCL). To reduce axi‐cel–related toxicity, several exploratory safety management cohorts were added to ZUMA‐1 (NCT02348216), the pivotal phase 1/2 study of axi‐cel in refractory LBCL. Cohort 4 evaluated the rates and severity of cytokine release syndrome (CRS) and neurologic events (NEs) with earlier corticosteroid and tocilizumab use. Primary endpoints were incidence and severity of CRS and NEs. Patients received 2 × 10⁶ anti‐CD19 CAR T cells/kg after conditioning chemotherapy. Forty‐one patients received axi‐cel. Incidences of any‐grade CRS and NEs were 93% and 61%, respectively (grade ≥ 3, 2% and 17%). There was no grade 4 or 5 CRS or NE. Despite earlier dosing, the cumulative cortisone‐equivalent corticosteroid dose in patients requiring corticosteroid therapy was lower than that reported in the pivotal ZUMA‐1 cohorts. With a median follow‐up of 14·8 months, objective and complete response rates were 73% and 51%, respectively, and 51% of treated patients were in ongoing response. Earlier and measured use of corticosteroids and/or tocilizumab has the potential to reduce the incidence of grade ≥ 3 CRS and NEs in patients with R/R LBCL receiving axi‐cel.

KTE-X19 for relapsed or refractory adult B-cell acute lymphoblastic leukaemia: phase 2 results of the single-arm, open-label, multicentre ZUMA-3 study

BACKGROUND

Despite treatment with novel therapies and allogeneic stem-cell transplant (allo-SCT) consolidation, outcomes in adult patients with relapsed or refractory B-precursor acute lymphoblastic leukaemia remain poor, underlining the need for more effective therapies.

METHODS

We report the pivotal phase 2 results of ZUMA-3, an international, multicentre, single-arm, open-label study evaluating the efficacy and safety of the autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy KTE-X19 in adult patients with relapsed or refractory B-precursor acute lymphoblastic leukaemia. Patients were enrolled at 25 sites in the USA, Canada, and Europe. Eligible patients were aged 18 years or older, with Eastern Cooperative Oncology Group performance status of 0-1, and morphological disease in the bone marrow (>5% blasts). After leukapheresis and conditioning chemotherapy, patients received a single KTE-X19 infusion (1 × 10⁶ CAR T cells per kg bodyweight). The primary endpoint was the rate of overall complete remission or complete remission with incomplete haematological recovery by central assessment. Duration of remission and relapse-free survival, overall survival, minimal residual disease (MRD) negativity rate, and allo-SCT rate were assessed as secondary endpoints. Efficacy and safety analyses were done in the treated population (all patients who received a dose of KTE-X19). This study is registered with ClinicalTrials.gov, NCT02614066.

FINDINGS

Between Oct 1, 2018, and Oct 9, 2019, 71 patients were enrolled and underwent leukapheresis. KTE-X19 was successfully manufactured for 65 (92%) patients and administered to 55 (77%). The median age of treated patients was 40 years (IQR 28-52). At the median follow-up of 16·4 months (13·8-19·6), 39 patients (71%; 95% CI 57-82, p<0·0001) had complete remission or complete remission with incomplete haematological recovery, with 31 (56%) patients reaching complete remission. Median duration of remission was 12·8 months (95% CI 8·7-not estimable), median relapse-free survival was 11·6 months (2·7-15·5), and median overall survival was 18·2 months (15·9-not estimable). Among responders, the median overall survival was not reached, and 38 (97%) patients had MRD negativity. Ten (18%) patients received allo-SCT consolidation after KTE-X19 infusion. The most common adverse events of grade 3 or higher were anaemia (27 [49%] patients) and pyrexia (20 [36%] patients). 14 (25%) patients had infections of grade 3 or higher. Two grade 5 KTE-X19-related events occurred (brain herniation and septic shock). Cytokine release syndrome of grade 3 or higher occurred in 13 (24%) patients and neurological events of grade 3 or higher occurred in 14 (25%) patients.

INTERPRETATION

KTE-X19 showed a high rate of complete remission or complete remission with incomplete haematological recovery in adult patients with relapsed or refractory B-precursor acute lymphoblastic leukaemia, with the median overall survival not reached in responding patients, and a manageable safety profile. These findings indicate that KTE-X19 has the potential to confer long-term clinical benefit to these patients.

FUNDING

Kite, a Gilead Company.

PET-guided eBEACOPP treatment of advanced-stage Hodgkin lymphoma (HD18): follow-up analysis of an international, open-label, randomised, phase 3 trial

BACKGROUND

The German Hodgkin Study Group's HD18 trial established the safety and efficacy of PET-guided eBEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone in escalated doses) for the treatment of advanced-stage Hodgkin lymphoma. However, because of a protocol amendment during the enrolment period (June 1, 2011) that changed standard treatment from eight to six cycles, the results of the HD18 trial have been partially immature. We report a prespecified 5-year follow-up analysis of the completed HD18 trial.

METHODS

HD18 was an international, open-label, randomised, phase 3 trial done in 301 hospitals and private practices in five European countries. Patients aged 18-60 years with newly diagnosed, advanced-stage Hodgkin lymphoma and an Eastern Cooperative Oncology Group performance status of 0-2 were recruited. After receiving an initial two cycles of eBEACOPP (1250 mg/m² intravenous cyclophosphamide [day 1], 35 mg/m² intravenous doxorubicin [day 1], 200 mg/m² intravenous etoposide [day 1-3], 100 mg/m² oral procarbazine [day 1-7], 40 mg/m² oral prednisone [day 1-14], 1·4 mg/m² intravenous vincristine [day 8], and 10 mg/m² intravenous bleomycin [day 8]), patients underwent a contrast-enhanced CT and PET scan (PET-2). Patients with positive PET-2 were randomly assigned to receive standard therapy (an additional six cycles of eBEACOPP; ie, eight cycles in total) or experimental therapy (an additional six cycles of eBEACOPP plus 375 mg/m² intravenous rituximab; ie, eight cycles in total) until June 1, 2011. After June 1, 2011, all patients with positive PET-2 were assigned to the updated standard therapy with an additional four cycles of eBEACOPP (ie, six cycles in total). Patients with negative PET-2 were randomly assigned (1:1) to receive standard therapy (an additional six cycles of eBEACOPP [ie, eight cycles in total] until June 1, 2011; an additional four cycles of eBEACOPP [ie, six cycles in total] after June 1, 2011) or experimental therapy (an additional two cycles of eBEACOPP; ie, four cycles in total). Randomisation was done centrally with the minimisation method, including a random component, stratified by centre, age, stage, international prognostic score, and sex. The primary endpoint was progression-free survival. HD18 aimed to improve 5-year progression-free survival by 15% in the PET-2-positive intention-to-treat cohort and to exclude inferiority of 6% or more in 5-year progression-free survival in the PET-2-negative per-protocol population. This study is registered with ClinicalTrials.gov, NCT00515554, and is completed.

FINDINGS

Between May 14, 2008, and July 18, 2014, 2101 patients were enrolled and 1945 were assigned to a treatment group according to their PET-2 result. In the PET-2-positive cohort, with a median follow-up of 73 months (IQR 59 to 94), 5-year progression-free survival was 89·9% (95% CI 85·7 to 94·1) in 217 patients assigned to eight cycles of eBEACOPP before the protocol amendment and 87·7% (83·1 to 92·4) in 217 patients assigned to eight cycles of rituximab plus eBEACOPP (p=0·40). Among 506 patients who received six cycles of eBEACOPP after the protocol amendment, 5-year progression-free survival was 90·1% (95% CI 87·2 to 92·9), with a median follow-up of 58 months (IQR 39 to 66). In the PET-2-negative cohort, with a median follow-up of 66 months (IQR 54 to 85) in the combined pre-amendment and post-amendment groups, 5-year progression-free survival was 91·2% (95% CI 88·4 to 93·9) in 446 patients who received eight or six cycles of eBEACOPP and 93·0% (90·6 to 95·4) in 474 patients who received four cycles of eBEACOPP (difference 1·9% [95% CI -1·8 to 5·5]). In the subgroup of PET-2-negative patients randomly assigned after protocol amendment, 5-year progression-free survival was 90·9% (95% CI 86·8 to 95·1) in 202 patients assigned to receive six cycles of eBEACOPP and 91·0% (86·6 to 95·5) in 200 patients assigned to receive four cycles of eBEACOPP (difference 0·1% [-5·9 to 6·2]).

INTERPRETATION

Long-term follow-up confirms the efficacy and safety of PET-2-guided eBEACOPP in patients with advanced-stage Hodgkin lymphoma. The reduction from eight to four cycles of eBEACOPP represents a benchmark in the treatment of early-responding patients, who can now be potentially cured with a short and safe treatment approach.

FUNDING

Deutsche Krebshilfe, Swiss State Secretariat for Education, Research and Innovation SERI (Switzerland), and Roche Pharma.

TRANSLATION

For the German translation of the abstract see Supplementary Materials section.

R-CHOP intensification with mid-cycle methotrexate and consolidating AraC/TT with BCNU/aHSCT in primary aggressive lymphoma with CNS involvement

Purpose

Patients suffering from aggressive systemic peripheral lymphoma with primary central nervous system involvement (PCL) are a rare and sparsely investigated population. Recommended treatment regimens include a combination of intrathecal and systemic chemotherapy as well as whole brain radiotherapy while offering relatively poor survival.

Methods

We conducted a single-center retrospective study that analyzed safety and outcome of 4 + 4 cycles Rituximab (R)-CHOP and R-high-dose Methotrexate (HD-MTX) for newly diagnosed, transplant-eligible patients (“Ping-Pong”), followed by Cytarabine (AraC)/Thiotepa (TT), BCNU/TT, and autologous hematologic stem cell transplantation (aHSCT). We retrospectively analyzed a set of 16 patients with high–intermediate or high-risk IPI status.

Results

Overall response rate to Ping-Pong was 100% measured by CT/MRI, including 93.75% complete remissions after BCNU/TT followed by PBSCT. One patient failed to qualify for high-dose chemotherapy due to progression when receiving Cytarabine/TT. All patients experienced grade III adverse events, 3 of them a grade IV adverse event. Estimated progression-free survival is 93.75% after a 4.8-year follow-up currently.

Conclusion

Our study suggests high effectivity of R-CHOP with mid-cycle MTX with aHSCT consolidation towards acceptable OS results in this challenging patient population.

Outcomes with KTE-X19 in patients (pts) with relapsed/refractory (R/R) mantle cell lymphoma (MCL) in ZUMA-2 who had progression of disease within 24 months of diagnosis (POD24)

7547

Background: KTE-X19 is an autologous anti-CD19 CAR T-cell therapy approved in the US and EU for the treatment of R/R MCL. In the ZUMA-2 study of KTE-X19 in R/R MCL, the objective response rate (ORR) at a median 17.5-mo follow-up was 92% (67% complete responses [CR]; Wang et al. ASH 2020 #1120). Here, we report results in pts with or w/o POD24, an indicator of poor outcomes (Visco et al. Br J Haematol 2019). Methods: Eligible pts with R/R MCL underwent leukapheresis and conditioning chemotherapy followed by a single infusion of KTE-X19. Efficacy results are reported for the 60 treated pts with ≥1 y of follow-up (median 17.5 mo); safety results are presented for all 68 treated pts. Results: High-risk disease characteristics were common in pts with (n=33) and w/o POD24 (n=35), although pts with POD24 had higher tumor burden and lactate dehydrogenase (LDH) levels, and more had blastoid type MCL (Table). ORR in pts with (n=28) and w/o POD24 (n=32) was 93% and 91%, with CR rates of 61% and 72%. In pts with and w/o POD24, median progression-free survival (PFS) was 11.3 mo (range, 0.9–30.3) and 29.3 mo (range, 0–35.9). Medians for duration of response (DOR) and overall survival (OS) were not reached in either group. Most common Grade ≥3 adverse events (AEs) in pts with vs w/o POD24 were neutropenia (91% vs 80%), thrombocytopenia (61% vs 46%), and anemia (55% vs 51%); Grade ≥3 cytokine release syndrome (CRS) and neurologic events occurred in 9% vs 20% and 27% vs 34%, respectively. There were no cases of Grade 5 CRS, KTE-X19–related secondary cancers, or replication-competent retrovirus in either group. In pts with vs w/o POD24, median peak CAR T-cell levels and median area under the curve were 53.4 cells/µL (range, 0.2–2566) and 583.4 cells/µL (range, 1.8–27,743.6) vs 112.4 cells/µL (range, 0.2–2589) and 1588.3 cells/µL (range, 3.8–27,238.7); by 12 mo, B cells were detectable in 8/11 (73%) vs 7/15 pts (47%) in ongoing response. Conclusions: KTE-X19 provided a high CR rate across all pts, with median DOR and OS not reached. Pts with POD24 had more aggressive high-risk disease characteristics (tumor burden, LDH levels, and blastoid MCL) and generally lower CAR T-cell expansion and PFS vs pts w/o POD24. Earlier intervention with CD19-directed CAR T-cell therapy may benefit pts with MCL with known high-risk factors. Clinical trial information: NCT02601313. [Table: see text]

Phase 2 results of the ZUMA-3 study evaluating KTE-X19, an anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, in adult patients (pts) with relapsed/refractory B-cell acute lymphoblastic leukemia (R/R B-ALL)

7002

Background: ZUMA-3 is a Phase 1/2 multicenter study evaluating KTE-X19, an autologous anti-CD19 CAR T-cell therapy, in adult pts with R/R B-ALL. Phase 1 efficacy results at the recommended Phase 2 dose (1×106 CAR T cells/kg) were encouraging (Shah et al. ASCO 2019 #7006). Here, we present the pivotal Phase 2 results. Methods: Eligible adults had R/R B-ALL, > 5% bone marrow (BM) blasts by local evaluation, and ECOG 0–1. Pts received a single infusion of KTE-X19 after conditioning chemotherapy. The primary endpoint was the overall complete remission (CR) rate (CR + CR with incomplete hematologic recovery [CRi]) by central review. Key secondary endpoints were duration of remission (DOR), relapse-free survival (RFS), overall survival (OS), measurable residual disease negativity (MRD–) rate by flow cytometry, and safety. Data are reported in all treated pts. Results: As of 9/2020, 55 of 71 enrolled pts received KTE-X19, with a median follow-up of 16.4 mo (range, 10.3–22.1). Adverse events (AEs; n = 8) and ineligibility (n = 4) were the most common reasons enrolled pts did not receive KTE-X19 infusion. Median age was 40 y (range, 19–84), median BM blasts at screening were 65% (range, 5–100), and 47% of pts had ≥3 prior therapies, with 45%, 22%, and 42% having previously received blinatumomab, inotuzumab ozogamicin, or allogeneic stem cell transplant (alloSCT), respectively. The CR/CRi rate was 71% (95% CI, 57–82; 56% CR, 15% CRi); 31% of responders had ongoing responses. Median (95% CI) DOR, RFS, and OS were 12.8 mo (8.7–not estimable [NE]), 11.6 mo (2.7–15.5), and 18.2 mo (15.9–NE), respectively. In responders, median (95% CI) RFS and OS were 14.2 mo (11.6–NE) and not reached (16.2–NE). The MRD– rate was 97% among pts with CR/CRi. Among 25 pts with prior blinatumomab treatment, the CR/CRi rate was 60%. Ten pts (18%) received subsequent alloSCT at a median 98 days post–KTE-X19 infusion. Median DOR remained unchanged when not censoring for alloSCT. Grade ≥3 AEs occurred in 95% of pts, most commonly anemia (49%) and neutropenia (49% [febrile 13%]). Grade ≥3 cytokine release syndrome (CRS; per Lee at al. Blood 2014) and neurologic events occurred in 24% and 25% of pts, respectively, and were generally reversible. Two Grade 5 KTE-X19–related events occurred (brain herniation, n = 1; septic shock, n = 1). Median times to onset of CRS and neurologic events were 5 d and 9 d, with median durations of 7.5 d and 7 d, respectively. Median peak CAR T-cell levels (cells/µL) were 40.5 (range, 1.3–1533.4) in pts with CR and 0 in nonresponders. CAR T cells were undetectable by 9 mo in ongoing responders. Conclusions: After a median follow-up of 16.4 mo, KTE-X19 demonstrated compelling clinical benefit in heavily pretreated adults with R/R B-ALL, with the median OS not yet reached for responding pts and a manageable safety profile. Clinical trial information: NCT02614066.

Intensified treatment of patients with early stage, unfavourable Hodgkin lymphoma: long-term follow-up of a randomised, international phase 3 trial of the German Hodgkin Study Group (GHSG HD14)

BACKGROUND

To improve the long-term tumour control in early, unfavourable Hodgkin Lymphoma, the German Hodgkin Study Group (GHSG) HD14 trial compared four cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) with an intensified chemotherapy regimen consisting of two cycles of escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (escalated BEACOPP) plus two cycles of ABVD. The final analysis of the trial showed a significant advantage in terms of freedom from treatment failure (difference 7·2% [95% CI 3·8-10·5] at 5 years) for patients who received two cycles of escalated BEACOPP and two cycles of ABVD. However, there was no difference in overall survival between the two groups. To evaluate long-term efficacy and toxicity of this strategy, we did a follow-up analysis.

METHODS

Patients aged 18-60 years with performance status of 2 or less and primary diagnosis of early, unfavourable Hodgkin lymphoma (all histologies) were included in an international, randomised, open-label, phase 3 trial. Patients were randomly assigned to receive four cycles of ABVD (ABVD group) or two cycles of escalated BEACOPP and two cycles of ABVD (2 + 2 group), both groups also received 30 Gy involved field radiotherapy. The ABVD dosing regimen was doxorubicin 25 mg/m² (days 1 and 15), bleomycin 10 mg/m² (days 1 and 15), vinblastine 6 mg/m² (days 1 and 15), and dacarbazine 375 mg/m² (days 1 and 15), repeated on day 29. The escalated BEACOPP dosing regimen was cyclophosphamide 1250 mg/m² (day 1), doxorubicin 35 mg/m² (day 1), etoposide 200 mg/m² (days 1-3), procarbazine 100 mg/m² (days 1-7), prednisone 40 mg/m² (days 1-14), vincristine 1·4 mg/m² (day 8; maximum 2 mg), and bleomycin 10 mg/m² (day 8), repeated on day 22. After closure of the ABVD group according to prespecified rules, patients were assigned to receive two cycles of escalated BEACOPP and two cycles of ABVD (non-randomised 2 + 2 group), which continued until the end of the predefined 5-year recruitment period. In this prespecified long-term follow-up analysis, we aimed to evaluate the secondary endpoints progression-free survival, overall survival, and long-term toxicity. To this end, we did a descriptive intention-to-treat analysis of all qualified HD14 patients and on the predefined subsets of randomised qualified HD14 patients and patients in the non-randomised 2 + 2 group. The trial was registered on the International Standard Randomised Controlled Trial database, 04761296.

FINDINGS

Between Jan 28, 2003, and Dec 29, 2009, 1686 patients were randomly assigned to the ABVD group (847 [50·2%] patients) and the 2 + 2 group (839 [49·8%] patients). 370 additional patients were recruited to the non-randomised 2 + 2 group. 1550 (92%) randomly assigned patients (median observation time 112 months [IQR 80-132]) and 339 (92%) patients in the non-randomised 2 + 2 group (median observation time 74 months [58-100]) were included in the qualified analysis set. 10-year overall survival in the randomly assigned patients was 94·1% (95% CI 92·0-95·7) for the ABVD group and 94·1% (91·8-95·7) for the 2 + 2 group (HR 1·0 [95% CI 0·6-1·5]; p=0·88). 8-year overall survival in the non-randomised 2 + 2 group was 95·1% (95% CI 91·6-97·2). 10-year progression-free survival in the randomly assigned patients was 85·6% (95% CI 82·6-88·1) for the ABVD group and 91·2% (88·4-93·3) for the 2 + 2 group (HR 0·5% [95% CI 0·4-0·7]; p=0·0001), accounting for a significant difference of 5·6% (95% CI 1·9-9·2) favouring the 2 + 2 group (p=0·0001). In the non-randomised 2 + 2 group, 8-year progression-free survival was 94·5% (95% CI 91·1-96·6). Standardised incidence ratios of second primary malignancies were similar between the ABVD group (2·3 [95% CI 1·6-3·1]) and the 2 + 2 group (2·5 [1·8-3·4]; Gray's p=0·80). Standardised incidence ratio of second primary malignancies was 3·1 (95% CI 1·7-5·0) in the non-randomised 2 + 2 group.

INTERPRETATION

This long-term analysis confirms superior tumour control in the 2 + 2 group compared with the ABVD group without translating into an overall survival difference. At longer follow-up, there is no difference regarding second primary malignancies between groups. In conclusion, the 2 + 2 regimen spares a significant number of patients from the burden of relapse and additional treatment without increased long-term toxicity.

FUNDING

Deutsche Krebshilfe eV and Swiss Federal Government.

Blinatumomab as first salvage versus second or later salvage in adults with relapsed/refractory B-cell precursor acute lymphoblastic leukemia: Results of a pooled analysis

Background

Blinatumomab is a BiTE^® immuno‐oncology therapy indicated for the treatment of patients with relapsed or refractory (r/r) B‐cell precursor (BCP) acute lymphoblastic leukemia (ALL).

Homozygous BCMA gene deletion in response to anti-BCMA CAR T cells in a patient with multiple myeloma

B cell maturation antigen (BCMA) is a target for various immunotherapies and a biomarker for tumor load in multiple myeloma (MM). We report a case of irreversible BCMA loss in a patient with MM who was enrolled in the KarMMa trial ( NCT03361748 ) and progressed after anti-BCMA CAR T cell therapy. We identified selection of a clone with homozygous deletion of TNFRSF17 (BCMA) as the underlying mechanism of immune escape. Furthermore, we found heterozygous TNFRSF17 loss or monosomy 16 in 37 out of 168 patients with MM, including 28 out of 33 patients with hyperhaploid MM who had not been previously treated with BCMA-targeting therapies, suggesting that heterozygous TNFRSF17 deletion at baseline could theoretically be a risk factor for BCMA loss after immunotherapy.

PET-guided omission of radiotherapy in early-stage unfavourable Hodgkin lymphoma (GHSG HD17): a multicentre, open-label, randomised, phase 3 trial

BACKGROUND

Combined-modality treatment consisting of chemotherapy and consolidation radiotherapy is standard of care for patients with early-stage unfavourable Hodgkin lymphoma. However, the use of radiotherapy can have long-term sequelae, which is of particular concern, as Hodgkin lymphoma is frequently diagnosed in young adults with a median age of approximately 30 years. In the German Hodgkin Study Group HD17 trial, we investigated whether radiotherapy can be omitted without loss of efficacy in patients who have a complete metabolic response after receiving two cycles of escalated doses of etoposide, cyclophosphamide, and doxorubicin, and regular doses of bleomycin, vincristine, procarbazine, and prednisone (eBEACOPP) plus two cycles of doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) chemotherapy (2 + 2).

METHODS

In this multicentre, open-label, randomised, phase 3 trial, patients (aged 18-60 years) with newly diagnosed early-stage unfavourable Hodgkin lymphoma (all histologies) and an Eastern Cooperative Oncology Group performance status of 2 or less were enrolled at 224 hospitals and private practices in Germany, Switzerland, Austria, and the Netherlands. Patients were randomly assigned (1:1) to receive either standard combined-modality treatment, consisting of the 2 + 2 regimen (eBEACOPP consisted of 1250 mg/m² intravenous cyclophosphamide on day 1, 35 mg/m² intravenous doxorubicin on day 1, 200 mg/m² intravenous etoposide on days 1-3, 100 mg/m² oral procarbazine on days 1-7, 40 mg/m² oral prednisone on days 1-14, 1·4 mg/m² intravenous vincristine on day 8 [maximum dose of 2 mg per cycle], and 10 mg/m² intravenous bleomycin on day 8; ABVD consisted of 25 mg/m² intravenous doxorubicin, 10 mg/m² intravenous bleomycin, 6 mg/m² intravenous vinblastine, and 375 mg/m² intravenous dacarbazine, all given on days 1 and 15) followed by 30 Gy involved-field radiotherapy (standard combined-modality treatment group) or PET4-guided treatment, consisting of the 2 + 2 regimen followed by 30 Gy of involved-node radiotherapy only in patients with positive PET at the end of four cycles of chemotherapy (PET4; PET4-guided treatment group). Randomisation was done centrally and used the minimisation method and seven stratification factors (centre, age, sex, clinical symptoms, disease localisation, albumin concentration, and bulky disease), and patients and investigators were masked to treatment allocation until central review of the PET4 examination had been completed. With the final analysis presented here, the primary objective was to show non-inferiority of the PET4-guided strategy in a per-protocol analysis of the primary endpoint of progression-free survival. We defined non-inferiority as an absolute difference of 8% in the 5-year progression-free survival estimates between the two groups. Safety analyses were done in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT01356680.

FINDINGS

Between Jan 13, 2012, and March 21, 2017, we enrolled and randomly assigned 1100 patients to the standard combined-modality treatment group (n=548) or to the PET4-guided treatment group (n=552); two patients in each group were found ineligible after randomisation. At a median follow-up of 46·2 months (IQR 32·7-61·2), 5-year progression-free survival was 97·3% (95% CI 94·5-98·7) in the standard combined-modality treatment group and 95·1% (92·0-97·0) in the PET4-guided treatment group (hazard ratio 0·523 [95% CI 0·226-1·211]). The between-group difference was 2·2% (95% CI -0·9 to 5·3) and excluded the non-inferiority margin of 8%. The most common grade 3 or 4 acute haematological adverse events were leucopenia (436 [83%] of 528 patients in the standard combined-modality treatment group vs 443 [84%] of 529 patients in the PET4-guided treatment group) and thrombocytopenia (139 [26%] vs 176 [33%]), and the most frequent acute non-haematological toxic effects were infection (32 [6%] vs 40 [8%]) and nausea or vomiting (38 [7%] vs 29 [6%]). The most common acute radiotherapy-associated adverse events were dysphagia (26 [6%] in the standard combined-modality treatment group vs three [2%] in the PET4-guided treatment group) and mucositis (nine [2%] vs none). 229 serious adverse events were reported by 161 (29%) of 546 patients in the combined-modality treatment group, and 235 serious adverse events were reported by 164 (30%) of 550 patients in the PET4-guided treatment group. One suspected unexpected serious adverse reaction (infection) leading to death was reported in the PET4-guided treatment group.

INTERPRETATION

PET4-negativity after treatment with 2 + 2 chemotherapy in patients with newly diagnosed early-stage unfavourable Hodgkin lymphoma allows omission of consolidation radiotherapy without a clinically relevant loss of efficacy. PET4-guided therapy could thereby reduce the proportion of patients at risk of the late effects of radiotherapy.

FUNDING

Deutsche Krebshilfe.

Improved Primary Staging of Marginal-Zone Lymphoma by Addition of CXCR4-Directed PET/CT

PET/CT with ¹⁸F-FDG is an integral component in the primary staging of most lymphomas. However, its utility is limited in marginal-zone lymphoma (MZL) because of inconsistent ¹⁸F-FDG avidity. One diagnostic alternative could be the targeting of C-X-C motif chemokine receptor 4 (CXCR4), shown to be expressed by MZL cells. This study investigated the value of adding CXCR4-directed ⁶⁸Ga-pentixafor PET/CT to conventional staging. Methods: Twenty-two newly diagnosed MZL patients were staged conventionally and with CXCR4 PET/CT. Lesions identified exclusively by CXCR4 PET/CT were biopsied as the standard of reference and compared with imaging results. The impact of CXCR4-directed imaging on staging results and treatment protocol was assessed. Results: CXCR4 PET/CT correctly identified all patients with viable MZL and was superior to conventional staging (P < 0.001). CXCR4-directed imaging results were validated by confirmation of MZL in 16 of 18 PET-guided biopsy samples. Inclusion of CXCR4 PET/CT in primary staging significantly impacted staging results in almost half of patients and treatment protocols in a third (upstaging, n = 7; downstaging, n = 3; treatment change, n = 8; P < 0.03). Conclusion: CXCR4 PET/CT is a suitable tool in primary staging of MZL and holds the potential to improve existing diagnostic algorithms.

Flotetuzumab as salvage immunotherapy for refractory acute myeloid leukemia

Approximately 50% of acute myeloid leukemia (AML) patients do not respond to induction therapy (primary induction failure [PIF]) or relapse after <6 months (early relapse [ER]). We have recently shown an association between an immune-infiltrated tumor microenvironment (TME) and resistance to cytarabine-based chemotherapy but responsiveness to flotetuzumab, a bispecific DART antibody-based molecule to CD3ε and CD123. This paper reports the results of a multicenter, open-label, phase 1/2 study of flotetuzumab in 88 adults with relapsed/refractory AML: 42 in a dose-finding segment and 46 at the recommended phase 2 dose (RP2D) of 500 ng/kg per day. The most frequent adverse events were infusion-related reactions (IRRs)/cytokine release syndrome (CRS), largely grade 1-2. Stepwise dosing during week 1, pretreatment dexamethasone, prompt use of tocilizumab, and temporary dose reductions/interruptions successfully prevented severe IRR/CRS. Clinical benefit accrued to PIF/ER patients showing an immune-infiltrated TME. Among 30 PIF/ER patients treated at the RP2D, the complete remission (CR)/CR with partial hematological recovery (CRh) rate was 26.7%, with an overall response rate (CR/CRh/CR with incomplete hematological recovery) of 30.0%. In PIF/ER patients who achieved CR/CRh, median overall survival was 10.2 months (range, 1.87-27.27), with 6- and 12-month survival rates of 75% (95% confidence interval [CI], 0.450-1.05) and 50% (95% CI, 0.154-0.846). Bone marrow transcriptomic analysis showed that a parsimonious 10-gene signature predicted CRs to flotetuzumab (area under the receiver operating characteristic curve = 0.904 vs 0.672 for the European LeukemiaNet classifier). Flotetuzumab represents an innovative experimental approach associated with acceptable safety and encouraging evidence of activity in PIF/ER patients. This trial was registered at www.clinicaltrials.gov as #NCT02152956.

Long-term survival of patients with relapsed/refractory acute lymphoblastic leukemia treated with blinatumomab

Background

Blinatumomab is a CD19 BiTE (bispecific T‐cell engager) immuno‐oncology therapy that mediates the lysis of cells expressing CD19.

Methods

A pooled analysis of long‐term follow‐up data from 2 phase 2 studies that evaluated blinatumomab in heavily pretreated adults with Philadelphia chromosome–negative, relapsed/refractory B‐cell precursor acute lymphoblastic leukemia was conducted.

Results

A total of 259 patients were included in the analysis. The median overall survival (OS) among all patients, regardless of response, was 7.5 months (95% confidence interval [CI], 5.5‐8.5 months); the median follow‐up time for OS was 36.0 months (range, 0.3‐60.8 months). The median relapse‐free survival (RFS) among patients who achieved a complete remission (CR) or complete remission with partial hematologic recovery (CRh) in the first 2 cycles (n = 123) was 7.7 months (95% CI, 6.2‐10.0 months); the median follow‐up time for RFS was 35.0 months (range, 9.5‐59.5 months). OS and RFS plateaued with 3‐year rates of 17.7% and 23.4%, respectively. The cumulative incidence function of the time to relapse, with death not due to relapse considered a competing risk, for patients who achieved a CR/CRh within 2 cycles of treatment also plateaued with a 3‐year relapse rate of 59.3%. For patients who achieved a CR/CRh with blinatumomab followed by allogeneic hematopoietic stem cell transplantation while in continuous CR, the median OS was 18.1 months (95% CI, 10.3‐30.0 months) with a 3‐year survival rate of 37.2%.

Conclusions

These data suggest that long‐term survival is possible after blinatumomab therapy.

Lay Summary

Immuno‐oncology therapies such as blinatumomab activate the patient's own immune system to kill cancer cells.

This study combined follow‐up data from 2 blinatumomab‐related clinical trials to evaluate long‐term survival in patients with relapsed and/or refractory B‐cell precursor acute lymphoblastic leukemia at high risk for unfavorable outcomes.

Among patients who achieved a deep response with blinatumomab, one‐third lived 3 years or longer. These findings suggest that long‐term survival is possible after treatment with blinatumomab.

Patients achieving remission after blinatumomab can have a durable response. The survival plateau indicates a high probability of a cure in those patients responding to blinatumomab and alive after 3 years.

Curative outcomes following blinatumomab in adults with minimal residual disease B-cell precursor acute lymphoblastic leukemia

Minimal residual disease (MRD) is the strongest predictor of relapse in B-cell precursor acute lymphoblastic leukemia (BCP-ALL). In BLAST study (NCT01207388), adults with BCP-ALL in remission with MRD after chemotherapy received blinatumomab, a CD19 BiTE^® immuno-oncotherapy, 15 µg/m²/day for up to four 6-week cycles (4 weeks continuous infusion, 2 weeks off). Survival was evaluated for 110 patients, including 74 who received HSCT in continuous complete remission. With a median follow-up of 59·8 months, median survival (months) was 36·5 (95% CI: 22.0-not reached [NR]). Median survival was NR (29.5-NR) for complete MRD responders (n = 84) and 14.4 (3.8-32.3) for MRD non-responders (n = 23; p = 0.002); after blinatumomab and HSCT, median survival was NR (25.7-NR) (n = 61) and 16.5 (1.1-NR) (n = 10; p = 0.065), respectively. This final analysis suggests complete MRD response during blinatumomab treatment is curative. Post-hoc analysis of study data suggests while post blinatumomab HSCT may be beneficial in appropriate patients, long-term survival without HSCT is also possible.

Retreatment (reTx) of patients (pts) with refractory large B-cell lymphoma with axicabtagene ciloleucel (axi-cel) in ZUMA-1

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Background: Axi-cel, an autologous anti-CD19 chimeric antigen receptor (CAR) T cell therapy, is approved in the US and EU for pts with relapsed/refractory large B cell lymphoma after ≥ 2 prior therapies. In the ZUMA-1 pivotal study (NCT02348216), the objective response rate (ORR) was 83% (58% complete response [CR] rate; Locke et al. Lancet Oncol. 2019). While axi-cel has demonstrated durable responses in a subset of pts, approximately half of all responders relapsed, and little is known on the viability of reTx with CAR T cell therapy. Here we report outcomes of pts retreated with axi-cel in ZUMA-1. Methods: Pts with progressive disease (PD) were eligible for reTx if there was no evidence of CD19 loss by local review, and if during 1st Tx they did not experience any dose-limiting toxicities, as defined in Phase 1, or comparable toxicities in Phase 2. Pts received the same regimen at reTx as at 1st Tx: 2 × 106 CAR T cells/kg after conditioning chemotherapy. Results: Thirteen pts in Cohorts 1 – 4 received axi-cel reTx. Prior to 1st Tx, most pts (69%) had an IPI score 3-4, 85% had disease stage 3-4, and the median number of prior regimens was 3 (range, 2 – 6). At first Tx, 6 pts achieved a CR, 6 achieved partial response (PR), and 1 pt had stable disease (SD) prior to PD. Median duration of first response was 96 days (range, 56 – 274). There was no Grade ≥ 3 cytokine release syndrome (CRS; 6 pts each had Grade 1 and 2). There were no Grade 4 or 5 neurologic events (NEs; 2 pts had Grade 1, 1 had Grade 2, and 7 had Grade 3). Upon reTx, 54% of pts achieved response (4 CR, 3 PR). Response to reTx was more common among pts who achieved CR at 1st Tx (83%; 4/6 CR, 1 PR, 1 SD) than in pts who achieved PR at 1st Tx (33%; 2/6 PR, 1 SD, 3 PD), and no response was observed in the pt with SD at 1st Tx. Median duration of response at reTx was 81 days (range, 1 – 225+). Response with reTx was longer than that with 1st Tx for 2 pts. One pt remains in response 255 days post-reTx. Comparable rates of CRS were observed with reTx as with 1st Tx. Compared with 1st Tx, fewer pts experienced NEs with reTx, and those that did occur were of lower grade: 23% (3 of 13 pts) had Grade 3; 23% (3 of 13 pts) had Grade 1, and 8% (1 of 13 pts) had Grade 2. Peak CAR T cell expansion was lower upon reTx vs 1st Tx (median, 4.3 vs 66.1 CAR gene-marked cells/µL blood). Conclusions: Based on this limited sample size, reTx with axi-cel may have clinical efficacy, although transient, in some pts, especially those who achieve CR with 1st Tx. CAR T cell expansion and severe CRS and NEs may be attenuated at reTx. Further studies with additional pts are needed to confirm these results. Clinical trial information: NCT02348216 .

KTE-X19 CAR T-Cell Therapy in Relapsed or Refractory Mantle-Cell Lymphoma

BACKGROUND

Patients with relapsed or refractory mantle-cell lymphoma who have disease progression during or after the receipt of Bruton's tyrosine kinase (BTK) inhibitor therapy have a poor prognosis. KTE-X19, an anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, may have benefit in patients with relapsed or refractory mantle-cell lymphoma.

METHODS

In a multicenter, phase 2 trial, we evaluated KTE-X19 in patients with relapsed or refractory mantle-cell lymphoma. Patients had disease that had relapsed or was refractory after the receipt of up to five previous therapies; all patients had to have received BTK inhibitor therapy previously. Patients underwent leukapheresis and optional bridging therapy, followed by conditioning chemotherapy and a single infusion of KTE-X19 at a dose of 2×10⁶ CAR T cells per kilogram of body weight. The primary end point was the percentage of patients with an objective response (complete or partial response) as assessed by an independent radiologic review committee according to the Lugano classification. Per the protocol, the primary efficacy analysis was to be conducted after 60 patients had been treated and followed for 7 months.

RESULTS

A total of 74 patients were enrolled. KTE-X19 was manufactured for 71 patients and administered to 68. The primary efficacy analysis showed that 93% (95% confidence interval [CI], 84 to 98) of the 60 patients in the primary efficacy analysis had an objective response; 67% (95% CI, 53 to 78) had a complete response. In an intention-to-treat analysis involving all 74 patients, 85% had an objective response; 59% had a complete response. At a median follow-up of 12.3 months (range, 7.0 to 32.3), 57% of the 60 patients in the primary efficacy analysis were in remission. At 12 months, the estimated progression-free survival and overall survival were 61% and 83%, respectively. Common adverse events of grade 3 or higher were cytopenias (in 94% of the patients) and infections (in 32%). Grade 3 or higher cytokine release syndrome and neurologic events occurred in 15% and 31% of patients, respectively; none were fatal. Two grade 5 infectious adverse events occurred.

CONCLUSIONS

KTE-X19 induced durable remissions in a majority of patients with relapsed or refractory mantle-cell lymphoma. The therapy led to serious and life-threatening toxic effects that were consistent with those reported with other CAR T-cell therapies. (Funded by Kite, a Gilead company; ZUMA-2 ClinicalTrials.gov number, NCT02601313.).

Anti-B-Cell Maturation Antigen BiTE Molecule AMG 420 Induces Responses in Multiple Myeloma

PURPOSE

The anti-B-cell maturation antigen BiTE molecule AMG 420 was assessed in patients with relapsed/refractory multiple myeloma.

PATIENTS AND METHODS

In this first-in-human study, up to 10 cycles of AMG 420 were given (4-week infusions/6-week cycles). Patients had progression after ≥ 2 lines of prior therapy and no extramedullary disease. Minimal residual disease (MRD) response was defined as < 1 tumor cell/10⁴ bone marrow cells by flow cytometry.

RESULTS

Forty-two patients received AMG 420 at 0.2-800 μg/d. Median age was 65 years, and median disease duration was 5.2 years. Median exposure was 1 cycle (range, 1-10 cycles) and 7 cycles (range, 1-10 cycles) for responders. Patients discontinued for disease progression (n = 25), adverse events (AEs; n = 7), death (n = 4), completion of 10 cycles (n = 3), and consent withdrawal (n = 1). Two patients remain on treatment. There were 2 nontreatment-related deaths from AEs, influenza/aspergillosis and adenovirus-related hepatitis. Serious AEs (n = 20; 48%) included infections (n = 14) and polyneuropathy (n = 2); treatment-related serious AEs included 2 grade 3 polyneuropathies and 1 grade 3 edema. There were no grade ≥ 3 CNS toxicities or anti-AMG 420 antibodies. In this study, 800 μg/d was considered to not be tolerable because of 1 instance each of grade 3 cytokine release syndrome and grade 3 polyneuropathy, both of which resolved. The overall response rate was 31% (n = 13 of 42). At the maximum tolerated dose (MTD) of 400 μg/d, the response rate was 70% (n = 7 of 10). Of these, five patients experienced MRD-negative complete responses, and 1 had a partial response, and 1 had a very good partial response; all 7 patients responded during the first cycle, and some responses lasted > 1 year.

CONCLUSION

In this study of AMG 420 in patients with relapsed/refractory multiple myeloma, the response rate was 70%, including 50% MRD-negative complete responses, at 400 μg/d, the MTD for this study.

Positron Emission Tomography-Guided Treatment in Early-Stage Favorable Hodgkin Lymphoma: Final Results of the International, Randomized Phase III HD16 Trial by the German Hodgkin Study Group

PURPOSE

Combined-modality treatment (CMT) with 2× ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) and small-field radiotherapy is standard of care for patients with early-stage favorable Hodgkin lymphoma (HL). However, the role of radiotherapy has been challenged. Positron emission tomography (PET) after 2× ABVD (PET-2) might help to predict individual outcomes and guide treatment.

METHODS

Between November 2009 and December 2015, we recruited patients age 18 to 75 years with newly diagnosed, early-stage favorable HL for this international randomized phase III trial. Patients were assigned to standard CMT of 2× ABVD and 20-Gy involved-field radiotherapy or PET-guided treatment, omitting involved-field radiotherapy after negative PET-2 (Deauville score < 3). Primary objectives were to exclude inferiority of 10% or more in 5-year progression-free survival (PFS) of ABVD alone compared with CMT in a per-protocol analysis among PET-2-negative patients (noninferiority margin for hazard ratio, 3.01) and to confirm PET-2 positivity (Deauville score ≥ 3) as a risk factor for PFS among CMT-treated patients.

RESULTS

We enrolled 1,150 patients. Median follow-up was 45 months. Among 628 PET-2-negative, per-protocol-treated patients, 5-year PFS was 93.4% (95% CI, 90.4% to 96.5%) with CMT and 86.1% (95% CI, 81.4% to 90.9%) with ABVD (difference 7.3% [95% CI, 1.6% to 13.0%]; hazard ratio, 1.78 [95% CI, 1.02 to 3.12]). Five-year overall survival was 98.1% (95% CI, 96.5% to 99.8%) with CMT and 98.4% (95% CI, 96.5% to 100.0%) with ABVD. Among 693 patients who were assigned to CMT, 5-year PFS was 93.2% (95% CI, 90.2% to 96.2%) among PET-2-negative patients and 88.4% (95% CI, 84.2% to 92.6%) in PET-2-positive patients (P = .047). When using the more common liver cutoff (Deauville score, 4) for PET-2 positivity, the difference was more pronounced (5-year PFS, 93.1% [95% CI, 90.7% to 95.5%] v 80.9% [95% CI, 72.2% to 89.7%]; P = .0011).

CONCLUSION

In early-stage favorable HL, a positive PET after two cycles ABVD indicates a high risk for treatment failure, particularly when a Deauville score of 4 is used as a cutoff for positivity. In PET-2-negative patients, radiotherapy cannot be omitted from CMT without clinically relevant loss of tumor control.

Transplantation in adults with relapsed/refractory acute lymphoblastic leukemia who are treated with blinatumomab from a phase 3 study

BACKGROUND

Blinatumomab, a bispecific T-cell-engaging (BiTE®) immuno-oncology therapy, demonstrated superior overall survival versus standard-of-care chemotherapy (SOC) in adults with relapsed/refractory B-cell precursor acute lymphoblastic leukemia (R/R ALL) in the phase 3 TOWER study. Herein, the authors reported clinical features and outcomes for those patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT) after treatment with blinatumomab.

METHODS

In the TOWER study, adults with R/R ALL were randomized 2:1 to receive blinatumomab or SOC. Study treatment consisted of 2 cycles of induction with blinatumomab or SOC followed by consolidation and maintenance therapy. At any time after the first cycle, patients who were eligible for HSCT could proceed to HSCT.

RESULTS

Of the 97 patients who underwent HSCT during the study, baseline characteristics generally were comparable and donor types were similar between the patients treated with blinatumomab (65 patients) and those receiving SOC (32 patients). There was no evidence to suggest that the survival benefit of HSCT differed between the patients treated with blinatumomab and those receiving SOC (P = .68). On the basis of descriptive statistics, a survival benefit of HSCT versus no HSCT was not observed in patients who achieved complete remission with full, partial, or incomplete hematologic recovery with blinatumomab (odds ratio, 1.17; 95% CI, 0.54-2.53). The best outcomes were achieved in patients with no prior salvage therapy and with minimal residual disease response to blinatumomab regardless of on-study HSCT status.

CONCLUSIONS

Survival was found to be driven by response to study treatment and by salvage status regardless of on-study HSCT status. These data should be interpreted with caution because the current study was not designed to prospectively assess survival outcomes associated with HSCT after blinatumomab.

LAY SUMMARY

Evidence before this study: Blinatumomab is associated with superior morphologic and molecular response rates and superior overall outcome when compared with standard of care chemotherapy in adults with relapsed/refractory B-cell precursor acute lymphoblastic leukemia. Added value of this study: The best outcomes with blinatumomab were observed in patients who achieved minimal residual disease remission in first salvage treatment regardless of subsequent allogeneic stem cell transplantation (HSCT). Implications of all the available evidence: Patients achieving CR/CRh/CRi following blinatumomab can have a durable response with or without HSCT.

The impact of infection on health-related quality of life (HRQoL) in patients with Philadelphia negative relapsed or refractory B-cell precursor acute lymphoblastic leukemia (Ph- R/R BCP ALL) in a randomized, open-label, phase 3 study (TOWER)

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Background: In the phase 3 TOWER study (NCT02013167), blinatumomab (BLIN) significantly improved overall survival in adults with Ph- R/R BCP ALL, and these patients (pts) also reported better HRQoL (EORTC QLQ-C30 measures) compared with standard of care (SOC) chemotherapy. This analysis assessed the impact of grade 3+ infection, which was reported in 34.1% of BLIN pts vs 52.3% of SOC pts, on HRQoL in TOWER. Methods: Pts were stratified into two groups: those with infection vs those without infection, between baseline and Day 8, Day 15, and Day 29. A difference-in-difference (DID) model investigated the impact of infection on HRQoL. A 5-point change is considered the minimum clinically important difference in the EORTC QLQ-C30 for between group comparisons (King et al. 1996). Results: In total, 342 pts (n = 247 BLIN; n = 95 SOC) had a non-missing baseline and ≥1 post-baseline HRQoL score for any scale. Grade 3+ infection was reported in 15 (4.5%) pts before Day 8, 49 (14.5%) pts before Day 15, and 76 (22.6%) pts before Day 29. Pts with grade 3+ infection reported clinical meaningful deterioration in global health status (GHS) score and in almost all functional subscales across timepoints assessed (Table). At Day 29, grade 3+ infection was associated with statistically significant and clinically meaningful deterioration in GHS and most functional scales (Table). Similar but smaller effects were also observed for symptom scales/items (data not shown). Conclusions: Grade 3+ infection in pts with Ph- R/R BCP ALL was associated with clinically meaningful deterioration in HRQoL. The lower incidence of infection in pts treated with BLIN vs SOC may have contributed to the improved HRQoL for pts treated with BLIN. Clinical trial information: NCT02013167. [Table: see text]

Evaluation of AMG 420, an anti-BCMA bispecific T-cell engager (BiTE) immunotherapy, in R/R multiple myeloma (MM) patients: Updated results of a first-in-human (FIH) phase I dose escalation study

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Background: Objectives of this study included assessing safety and activity of AMG 420/BI 836909, which binds BCMA (B-Cell Maturation Antigen) on MM cells and CD3 on T cells, in relapsed and/or refractory (R/R) MM. Methods: In this FIH study, 6-week cycles of AMG 420 were given for ≤5 cycles or until disease progression (PD), toxicity, or consent withdrawal; 5 more cycles could be given for benefit. Eligible patients had progression after ≥2 lines (incl PI and IMiD). Excluded were PC leukemia, extramedullary relapse, CNS involvement, or prior allo-SCT. MRD was defined as <1 tumor cell / 104 bone marrow cells per flow cytometry. Results: As of Dec 10, 2018, 42 patients received AMG 420 (0.2-800 µg/d). Patients D/C for PD (n=24), adverse events (AE, n=7, incl 3 DLTs), death (4), completed 10 cycles (2), and consent (1). Median age was 65 y, median MM duration 5.2 y, and median # prior therapies 4. Patients were treated for a mean (SD) of 2.5 (2.6) cycles. There were 2 deaths from AEs (acute respiratory distress from flu / aspergillosis; fulminant hepatitis related to adenovirus infection); neither treatment related. Of those with serious AEs (SAEs, n=21, 50%), 18 required hospitalization. SAEs occurring in >1 patient were infections (n=12) and polyneuropathy (PN, n=2). Treatment-related SAEs included 2 grade 3 PNs and 1 edema. Grade 2-3 CRS was seen in 3 patients. No anti-AMG 420 Ab were detected. In this study, 800 µg/d was determined to not be tolerable as 2/3 patients had DLTs, 1 case of grade 3 CRS and 1 case of grade 3 PN; both required hospitalization and subsequently resolved. At 400 µg/d, there were 5 minimal residual disease (MRD)-negative sCRs, 1 VGPR, and 1 PR, for a response rate of 7/10 (70%); at Dec datacut, responses lasted for 5.6-10.4 months with 4 patients ongoing on treatment. As of Feb 2019, some responses lasted >1 year. Overall, there were 13/42 responders (6 sCRs, 3 CRs, 2 VGPRs, 2 PRs). Median time to any response was 1 month. Conclusions: In this FIH study of AMG 420, a BiTE vs BCMA, in R/R MM, there was a 70% response rate (7/10) with 5 out of 7 responders achieving a sCR at 400 µg/d, a recommended dose for further investigation. Clinical trial information: NCT02514239.

Preliminary results of earlier steroid use with axicabtagene ciloleucel (axi-cel) in patients with relapsed/refractory large B-cell lymphoma (R/R LBCL)

7558

Background: Axi-cel is an autologous anti-CD19 chimeric antigen receptor (CAR) T cell therapy approved in the EU and US for patients (pts) with R/R LBCL with ≥ 2 prior systemic therapies. In the 2-y follow-up of ZUMA-1, the objective response rate (ORR) was 83% with a complete response (CR) rate of 58%. Grade ≥ 3 cytokine release syndrome (CRS) and neurologic events (NE) occurred in 11% and 32% of pts, respectively; 26% of pts received steroids, and 43% received tocilizumab (Locke et al. Lancet Oncol. 2019). A safety expansion cohort was added to evaluate the effect of earlier steroid use on the rates of these adverse events (AEs). Methods: Eligible pts with R/R LBCL were leukapheresed and received conditioning chemotherapy followed by a target dose of 2 × 106 anti-CD19 CAR T cells/kg. Pts in this cohort received early steroid intervention starting at Grade 1 NE and at Grade 1 CRS when no improvement was observed after 3 days of supportive care. The primary endpoint for this cohort was incidence and severity of CRS and NE. Results: As of 9/14/2018, 21 of 40 planned pts received axi-cel with a minimum follow-up of 1 mo (median, 2.6 mo). The median age was 63 y (range, 36 – 73), 67% were male, 81% had disease stage III-IV, 76% were R/R to ≥ second-line therapy, and 10% had relapsed post-autologous stem cell transplantation. Seventy-six percent of pts received steroids and 81% received tocilizumab. Most pts (81%) had Grade ≥ 3 AEs, most commonly neutrophil count decreased (33%), anemia (29%), and pyrexia (24%). Grade ≥ 3 NE occurred in 10% of pts; the most common symptoms were somnolence (10%) and confusional state (10%). Grade 1 and 2 NE occurred in 38% and 5% of pts, respectively. No pt had Grade ≥ 3 CRS; 33% of pts had Grade 1 CRS and 67% had Grade 2. There were no deaths due to AEs; 1 pt died due to disease progression. The ORR per investigator assessment was 76% with 48% of pts achieving a CR. Pharmacokinetic data will be presented. Conclusions: Early use of steroids may help in managing severe CRS and NE by potentially reducing their incidence in pts treated with CAR T cell therapy without affecting response rates. Optimizing AE management may help to further improve the benefit:risk profile of CAR T cell therapy. Clinical trial information: NCT02348216.

Blinatumomab for Acute Lymphoblastic Leukemia Relapse after Allogeneic Hematopoietic Stem Cell Transplantation

Patients with relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL) following allogeneic hematopoietic stem cell transplantation (alloHSCT) have a poor prognosis, and alternative therapies are needed for this patient population. Blinatumomab, a bispecific T cell engager immunotherapy, was evaluated in an open-label, single-arm, phase II study of adults with R/R Philadelphia chromosome-negative B cell precursor ALL and resulted in a rate of complete remission (CR) or CR with partial hematologic recovery of peripheral blood counts (CRh) of 43% within 2 treatment cycles. We conducted an exploratory analysis to determine the efficacy and safety of blinatumomab in 64 patients who had relapsed following alloHSCT before enrollment in the phase II study. Forty-five percent of the patients (29 of 64) achieved a CR/CRh within the first 2 cycles of treatment, 22 of whom had a minimal residual disease (MRD) response (including 19 with a complete MRD response). After 1 year and 3 years of follow-up, the median relapse-free survival was 7.4 months for patients who achieved CR/CRh in the first 2 cycles, and the median overall survival was 8.5 months; overall survival rate (Kaplan-Meier estimate) was 36% at 1 year and 18% at 3 years. Grade 3 and 4 adverse events were reported in 20 patients (31%) and 28 patients (44%), respectively, with grade 3 and 4 neurologic events in 8 and 2 patients, respectively, and grade 3 cytokine release syndrome in 2 patients. Eight patients had fatal adverse events, including 5 due to infections. Seven patients had grade ≤ 3 graft-versus-host disease during the study, none of which resulted in the discontinuation of blinatumomab or hospitalization. Our data suggest that blinatumomab is an effective salvage therapy in this patient population.