Combination of rituximab and methotrexate followed by rituximab and cytarabine in elderly patients with primary central nervous system lymphoma.

The optimal treatment strategy for newly diagnosed primary central nervous system lymphoma (PCNSL) has yet to be established, especially in the elderly. In the current study, we conducted a phase II study to evaluate the efficacy and safety of rituximab plus high-dose MTX followed by rituximab plus cytarabine in patients aged ≥60 years newly diagnosed with PCNSL. Patients received an induction treatment of high-dose methotrexate plus rituximab followed by two cycles of a consolidation treatment of cytarabine plus rituximab. The primary end-point was a 2-year progression-free survival (PFS) rate. A total of 35 patients were recruited, and their median age was 73 (range: 60-81). After induction treatment, the complete and partial responses (PRs) were 56% and 20% respectively. Twenty-six patients proceeded to the consolidation treatment; the complete and PRs were 59% and 9% respectively. After a median follow-up duration of 36.0 months, the 2-year PFS rate was 58.7%. Treatment was generally well-tolerated as only three patients were withdrawn from the study due to toxicity, and no treatment-related mortality was reported. The 2-year overall survival rate was 77.9%. The current study may suggest the feasibility of administering high-dose MTX plus cytarabine in PCNSL patients aged ≥60 years and the potential role of additive rituximab.

Long-term survival outcomes of 'watch and wait' in patients with bronchus-associated lymphoid tissue lymphoma: a multicenter real-world data analysis in Korea.

Bronchus-associated lymphoid tissue (BALT) is a rare cause of extranodal marginal zone lymphoma (MZL). Although most patients with BALT lymphoma (BALToma) show an indolent clinical course and are monitored without treatment, there are limited real-world data on the long-term outcome of "watch-and-wait' strategy in comparison with other treatments. The survival outcomes of patients newly diagnosed with BALToma at three tertiary hospitals in Korea undergoing two treatment strategies were analyzed: group A, patients who were monitored without any treatment or received only radiotherapy after diagnosis; and group B, patients receiving any kind of systemic chemotherapy after diagnosis, regardless of their history of any local treatment such as surgery or radiotherapy. Of the 67 patients included in our analysis, the 10-year progression-free survival (PFS) and 10-year overall survival (OS) rates were 65.3% and 83.2%, respectively. The 10-year PFS rates for observation or localized treatment and systemic chemotherapy were 78.7% and 56.9%, respectively (p = 0.044). Ten-year OS rates for observation or localized treatment and systemic chemotherapy were 100% and 71.7%, respectively (p = 0.016). Multivariate analysis showed that bilateral lung (HR 2.462, p = 0.047) and extrapulmonary organ (HR 4.485, p = 0.004) involvement were the only significant factors associated with poor PFS. Prognostic factor analysis for OS did not yield significant results. Patients with BALToma show a favorable prognosis, suggesting that observation or localized therapy alone may be effective for patient management. However, patients with bilateral lung or extrapulmonary involvement may require careful monitoring for disease progression and more aggressive treatment approaches.

Assessing the Efficacy of Bortezomib and Dexamethasone for Induction and Maintenance Therapy in Relapsed/Refractory Cutaneous T-Cell Lymphoma: A Phase II CISL1701/BIC Study.

Purpose: This multicenter, open-label, phase II trial evaluated the efficacy and safety of bortezomib combined with dexamethasone for the treatment of relapsed/refractory cutaneous T-cell lymphoma (CTCL) in previously treated patients across 14 institutions in South Korea. Patients and Methods: Between September 2017 and July 2020, 29 patients with histologically confirmed CTCL received treatment, consisting of eight 4-week cycles of induction therapy followed by maintenance therapy, contingent upon response, for up to one year. The primary endpoint was the proportion of patients achieving an objective global response. Results: Thirteen (44.8%) of the 29 patients achieved an objective global response, including two complete responses. The median progression-free survival (PFS) was 5.8 months, with responders showing a median PFS of 14.0 months. Treatment-emergent adverse events were generally mild, with a low incidence of peripheral neuropathy and hematologic toxicities. Despite the trend toward shorter PFS in patients with higher mutation burdens, genomic profiling before and after treatment showed no significant emergence of new mutations indicative of disease progression. Conclusion: This study supports the use of bortezomib and dexamethasone as a viable and safe treatment option for previously treated CTCL, demonstrating substantial efficacy and manageability in adverse effects. Further research with a larger cohort is suggested to validate these findings and explore the prognostic value of mutation profiles.

CHRONOS-4: Phase 3 study of copanlisib plus rituximab-based immunochemotherapy in relapsed indolent B-cell lymphoma.

Copanlisib, a pan-class I phosphatidylinositol 3-kinase inhibitor with predominant activity against the α and δ isoforms, previously demonstrated durable responses as monotherapy and improved progression-free survival (PFS) in combination with rituximab in patients with relapsed indolent non-Hodgkin lymphoma (iNHL). CHRONOS-4 was a phase 3, randomized, double-blind, placebo-controlled study to investigate the efficacy and safety of copanlisib in combination with standard immunochemotherapy in patients with relapsed iNHL. Patients (n=524) were randomized (1:1) to copanlisib (60 mg IV) plus immunochemotherapy (rituximab and bendamustine [R-B] or placebo plus R-B). Copanlisib/placebo were administered with R-B (days 1, 8, and 15 of each 28-day cycle) for ≤6 cycles and as monotherapy from cycle 7 up to 12 months. The primary study endpoint was PFS. Median exposure was 8.5 months (0.2-12.9) for copanlisib plus R-B and 11.4 months (0.1-12.6) for placebo plus R-B. Median PFS was 32.9 months (95% CI, 24.4-38.6) for copanlisib plus R-B and 33.3 months (95% CI, 27.8-42.8) for placebo plus R-B (HR, 1.13 [95% CI, 0.88-1.44]; P=0.83). No differences between treatment arms were observed in overall survival (data not yet mature), objective response rate, and duration of response for the overall population or individual histology types. Overall, copanlisib plus R-B was associated with higher rates of serious treatment-emergent adverse events (TEAEs), grade 4 and 5 TEAEs, and treatment discontinuation. A number of serious TEAEs were infections. Overall, copanlisib plus R-B did not provide clinical benefit versus placebo plus R-B and was associated with worse tolerability in patients with relapsed iNHL. ClinicalTrials.gov: NCT02626455.

Phase 2 Trial of the Farnesyltransferase Inhibitor Tipifarnib for Relapsed/Refractory Peripheral T Cell Lymphoma.

A phase 2, international, open-label, non-randomized, single-arm trial was conducted to evaluate the efficacy and safety of tipifarnib, a farnesyltransferase inhibitor, as monotherapy for relapsed/refractory peripheral T-cell lymphoma (PTCL) and to evaluate tumor mutation profile as a biomarker of response. Adults with relapsed/refractory PTCL received tipifarnib 300 mg orally twice daily for 21 days in a 28-day cycle. The primary endpoint was objective response rate (ORR); secondary endpoints included ORR, progression-free survival (PFS), duration of response (DOR), and adverse events (AEs) in specific subtypes. Sixty-five patients with PTCL were enrolled: n=38 angioimmunoblastic T-cell lymphoma (AITL), n=25 PTCL not otherwise specified (PTCL-NOS), and n=2 other T-cell lymphomas. The ORR was 39.7% (95% CI, 28.1-52.5) in all patients and 56.3% (95% CI, 39.3-71.8) for AITL. Median PFS was 3.5 months overall (954% CI, 2.1-4.4), and 3.6 months (95% CI, 1.9-8.3) for AITL. Median DOR was 3.7 months (95% CI, 2.0-15.3), and greatest in AITL patients (7.8 months; 95% CI, 2.0-16.3). The median overall survival was 32.8 months (95% CI, 14.4 to not applicable). Tipifarnib-related hematologic AEs were manageable and included: neutropenia (43.1%), thrombocytopenia (36.9%), and anemia (30.8%); other tipifarnib-related AEs included nausea (29.2%) and diarrhea (27.7%). One treatment-related death occurred. Mutations in RhoA, DNMT3A, and IDH2 were seen in 60%, 33%, and 27%, respectively, in the AITL tipifarnib responder group vs 36%, 9%, and 9% in the non-responder group. Tipifarnib monotherapy demonstrated encouraging clinical activity in heavily pre-treated relapsed/refractory PTCL, especially in AITL, with a manageable safety profile. ClinicalTrials.gov NCT02464228.

QuantiFERON monitor predicts early cytomegalovirus infection and viral burden in allogeneic hematopoietic stem cell transplantation.

INTRODUCTION: Cytomegalovirus (CMV) infection is a major cause of transplantation-related morbidity and mortality. This study assessed the utility of the QuantiFERON monitor (QFM; Qiagen) for the prediction of early CMV infection and viral burden. METHODS: QuantiFERON-CMV (QF-CMV; Qiagen) and QFM were measured at the post-allogeneic hematopoietic stem cell transplantation (HSCT) week 4. CMV DNA was measured at every visit until post-HSCT week 24. The QFM cutoff specific to CMV infection was established. RESULT: At the post-HSCT week 4, the QFM cutoff predicting CMV infection was 86.95 IU/mL. While QF-CMV results at the post-HSCT week 4 were associated with high-level CMV infection (CMV DNA ≥ 5,000 IU/mL) but not with CMV infection (CMV DNA ≥ 500 IU/mL), QFM was associated with both CMV infection and high-level CMV infection. Both indeterminate QF-CMV and nonreactive QFM were associated with increased peak CMV DNA. CONCLUSION: Low QFM is a risk factor for CMV infection and increased CMV viral loads. QFM at post-HSCT week 4 can be utilized as an assay to predict the risk and burden of early CMV infection in HSCT recipients, in conjunction with other risk factors.

Peripheral T-cell lymphoma: From biology to practice to the future.

Recent advancements in comprehending peripheral T-cell lymphomas (PTCLs) validate and broaden our perspective, highlighting their diverse nature and the varying molecular mechanisms underlying the entities. Based on a comprehensive accumulated understanding, the PTCLs currently overcome the most challenging features of any disease: rarity, incredible heterogeneity, and a lack of any established standard of care. The treatments deployed in the front-line are extrapolated from regimens developed for other diseases. The recent approval of the three drugs brentuximab vedotin (BV), pralatrexate, and belinostat for patients with relapsed or refractory disease has provided clues about pathophysiology and future directions, though challenges satisfying post-marketing requirements (PMR) for those accelerated approvals have led to one of those drugs being withdrawn and put the other two in jeopardy. Edits of the front-line regimens, often called CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)-plus approaches, look more like CHOP-minus strategies, as the toxicity of five-drug regimens often reduces the dose intensity of the added 'novel' drug, nullifying any hope of an advance. The turmoil in the field produced by the aforementioned, coupled with an ever-changing classification, has left the field uncertain about the path forward. Despite these challenges, empiric findings from studies of novel drug approaches, coupled with a logic emerging from studies of PTCL lymphomagenesis, have begun to illuminate, albeit faintly for some, a potential direction. The empiric finding that drugs targeting the discrete components of the PTCL epigenome, coupled with the description of multiple mutations in genes that govern epigenetic biology, offers, at the very least, an opportunity to finally be hypothesis-driven. The most recent recognition that the only combination of drugs shown to markedly improve progression-free survival (PFS) in patients with relapsed disease is one based on dual targeting of different and discrete components of that epigenetic biology has established a possibility that circumnavigating chemotherapy addition studies is both plausible, feasible, and likely the best prospect for a quantum advance in this disease. Herein, we analyze PTCL through a 2025 lens, highlighting and underscoring walls that have impeded progress. We will critically explore all the clues and the panoramic view of PTCL research.

Long-term efficacy and safety of tucidinostat in patients with relapsed or refractory peripheral T-cell lymphoma: final analysis of phase IIb results.

Not available.

CAR T cells vs bispecific antibody as third- or later-line large B-cell lymphoma therapy: a meta-analysis.

ABSTRACT: This meta-analysis evaluates the efficacy and safety of chimeric antigen receptor (CAR) T-cell therapy and bispecific antibodies for relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL). We searched MEDLINE, Embase, and Cochrane databases until July 2023 for trials assessing CAR T-cell therapies and CD20×CD3 bispecific antibodies as third or subsequent lines in R/R DLBCL. Random-effects models estimated the complete response (CR) rate and secondary outcomes, with meta-regressions adjusting for relevant covariates. Sixteen studies comprising 1347 patients were included in the pooled analysis. The pooled CR rate for bispecific antibodies was 0.36 (95% confidence interval [CI], 0.29-0.43), compared with 0.51 (95% CI, 0.46-0.56) for CAR T-cell therapy (P < .01). This superiority persisted when comparing the CAR T-cell-naive patients within the bispecific antibody group, with a CR rate of 0.37 (95% CI, 0.32-0.43). Multivariable meta-regression also revealed better efficacy of CAR T cells with adjustment for the proportion of double-hit lymphoma. The pooled 1-year progression-free survival rate mirrored these findings (0.32 [95% CI, 0.26-0.38] vs 0.44 [95% CI, 0.41-0.48]; P < .01). For adverse events of grade ≥3, the bispecific antibody had incidences of 0.02 (95% CI, 0.01-0.04) for cytokine release syndrome, 0.01 (95% CI, 0.00-0.01) for neurotoxicity, and 0.10 (95% CI, 0.03-0.16) for infections. The CAR T cell had rates of 0.08 (95% CI, 0.03-0.12), 0.11 (95% CI, 0.06-0.17), and 0.17 (95% CI, 0.11-0.22), respectively, with significant differences observed in the first 2 categories. In summary, CAR T-cell therapy outperformed bispecific antibody in achieving higher CR rates, although with an increase in severe adverse events.

Optimization of immune checkpoint inhibitor treatment planning for relapsed or refractory extranodal NK/T cell lymphoma.

Pembrolizumab (anti-programmed cell death-ligand 1 inhibitor) is a promising salvage therapeutic option for relapsed/refractory extranodal NK/T-cell lymphoma (R/R ENKTL). However, the appropriate duration of pembrolizumab use in R/R ENKTL patients and the optimal timing for administering pembrolizumab remain undetermined. We collected and analyzed clinical information on R/R ENKTL 58 patients who received pembrolizumab to evaluate the optimal treatment durations and clinical information for considering treatment interruption. Treatment outcomes were assessed by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and Epstein Barr virus DNA (EBV DNA) every 3 months. Nineteen (32.8%) patients had been treated with more than three chemotherapies before pembrolizumab administration. The best response rate towards the first try of pembrolizumab was 38.9% (31.5% complete response rate (CR), 7.4% partial response (PR)). During the 41.8-month median follow-up duration, the median progression-free survival (PFS) was 3.1 months, and the median overall survival (OS) was 7.1 months. The failure group, which was characterized by Deaville score (DS) 3-4 and circulating EBV detection, or DS 5 with/without EBV detection, had the worst PFS (p < 0.001) and OS (p < 0.001), followed by the high (DS 1-2 and EBV detection, or DS 3-4 and EBV not detected) and low-risk groups (DS 1-2 and EBV not detected). Among the 21 patients who achieved the best response at the first pembolizumab try, the patients who received planned 24 cycles presented better PFS than those who received incomplete cycles (57.6 months vs 20.9 months, P-value = 0.012). Among 13 patients who received avelumab or pembrolizumab in advance, a few who responded to the second trial of pembrolizumab administration had over one year of chemotherapy vacation. Determining the discontinuation or continuation of pembrolizumab would be considered in selected cases assessed by PET-CT and EBV monitoring. Disruption of pembrolizumab treatment may be advisable for the low-risk group(DS 1-2 and EBV not detected), whereas continuation could be warranted for the high-risk group (DS 1-2 and EBV detection, or DS 3-4 and EBV not detected). Moreover, it might be critical to maintain over 24 cycles to improve the survival outcome of R/R ENKTL.

ASCT2-Targeting Antibody-Drug Conjugate MEDI7247 in Adult Patients with Relapsed/Refractory Hematological Malignancies: A First-in-Human, Phase 1 Study.

BACKGROUND: MEDI7247 is a first-in-class antibody-drug conjugate (ADC) consisting of an anti-sodium-dependent alanine-serine-cysteine transporter 2 antibody-conjugated to a pyrrolobenzodiazepine dimer. OBJECTIVE: This first-in-human phase 1 trial evaluated MEDI7247 in patients with hematological malignancies. PATIENTS AND METHODS: Adults with acute myeloid leukemia (AML), multiple myeloma (MM), or diffuse large B-cell lymphoma (DLBCL) relapsed or refractory (R/R) to standard therapies, or for whom no standard therapy exists, were eligible. Primary endpoints were safety and determination of the maximum tolerated dose (MTD). Secondary endpoints included assessments of antitumor activity, pharmacokinetics (PK), and immunogenicity. RESULTS: As of 26 March 2020, 67 patients were treated (AML: n = 27; MM: n = 18; DLBCL: n = 22). The most common MEDI7247-related adverse events (AEs) were thrombocytopenia (41.8%), neutropenia (35.8%), and anemia (28.4%). The most common treatment-related grade 3/4 AEs were thrombocytopenia (38.8%), neutropenia (34.3%), and anemia (22.4%). Anticancer activity (number of responders/total patients evaluated) was observed in 11/67 (16.4%) patients. No correlation was observed between ASCT2 expression and clinical response. Between-patient variability of systemic exposure of MEDI7247 ADC and total antibody were high (AUCinf geometric CV%: 62.3-134.2, and 74.8-126.1, respectively). SG3199 (PBD dimer) plasma concentrations were below the limit of quantification for all patients after Study Day 8. Anti-drug antibody (ADA) prevalence was 7.7%, ADA incidence was 1.9%, and persistent-positive ADA was 5.8%. CONCLUSIONS: Thrombocytopenia and neutropenia limited repeat dosing. Although limited clinical activity was detected, the dose-escalation phase was stopped early without establishing an MTD. The study was registered with ClinicalTrials.gov (NCT03106428).

Durable Responses With Mosunetuzumab in Relapsed/Refractory Indolent and Aggressive B-Cell Non-Hodgkin Lymphomas: Extended Follow-Up of a Phase I/II Study.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.Mosunetuzumab is a CD20xCD3 T-cell-engaging bispecific antibody administered as an off-the-shelf, fixed-duration treatment in an outpatient setting. We report an updated analysis of the durability of response, by investigator assessment, after an overall median follow-up of 3.5 years in patients with relapsed/refractory indolent or aggressive B-cell non-Hodgkin lymphoma (iNHL/aNHL) from the dose-escalation stage of a phase I/II study of mosunetuzumab (ClinicalTrials.gov identifier: NCT02500407). Across dose levels, 65.7% of patients with iNHL and 36.4% with aNHL achieved a complete or partial response to mosunetuzumab. Median duration of response (DoR) in patients with iNHL for all responders was 23.2 months (95% CI, 13.8 to not estimable [NE]), but was not reached in complete responders (95% CI, 21.0 to NE). After a median time on study of 38.9 months, no relapses were observed beyond 26 months in complete responders. In patients with aNHL, median DoR for all responders was 7.8 months (95% CI, 4.6 to 22.8). Among 12 complete responders who progressed postmosunetuzumab treatment and were retreated with mosunetuzumab, 83.3% had an objective response and 58.3% achieved a second complete response. Our study reports the longest follow-up using bispecific antibodies in patients with B-cell non-Hodgkin lymphoma and demonstrates that mosunetuzumab can mediate durable remissions with time-limited treatment.

Primary nodal Epstein-Barr virus-positive T-cell/NK-cell lymphoma: Real-world experience.

PTCL-EBV is a disease entity newly recognized in the WHO-HAEMS5 and the ICC of Mature Lymphoid neoplasms classification. Previously, it was classified as a subtype within PTCL-NOS and was known to have a poor prognosis. However, the clinical feature and treatment outcomes are not well known. This retrospective observational study was conducted on patients diagnosed with PTCL-EBV at Samsung Medical Center through a pathology review from 2000 to 2020. We analyzed clinical data from 14 patients. We conducted an investigation of patients with PTCL-EBV into immunohistochemistry and analysis of survival outcomes for each treatment regimen. We analyzed both overall survival and progression-free survival for each treatment regimen. 25% were beta-F1 positive, and 67% were TCRγ positive. TIA-1 and granzyme B exhibited positive results in all cases, whereas the NK cell marker CD56 was negative in only 11% of patients. The CD3 was observed in all of patients. And, the CD4 was 43% positive. The CD8 were investigated in 8 patients, with 37.5% positive. Hepatosplenomegaly was observed in 55% of patients, and 70% of patients displayed B symptoms at the time of diagnosis. Patients who received CHOP or CVP treatment had a median PFS of 2.2 months (95% CI 1.9-2.5 months), and patients who received other treatments had a median PFS of 5.1 months (NA). The objective response rate (ORR) for ICE/dexa as the first or second line treatment was 100% (3 out of 3). But, ORR of CHOP or CVP as the first line treatment was 33.3% (3 out of 9). The median overall survival (OS) for the group that received HSCT after achieving a response was 34.6 months (95% CI 0-74.6 months), and the median OS for the group that did not receive HSCT was 5.0 months (95% CI 2.1-7.9 months) (p=0.04). In conclusion, in the context of PTCL-EBV, despite a limited sample size, the ICE/Dexa regimen shows potential benefits in terms of ORR and PFS. Furthermore, the application of HSCT following the attainment of a complete response may prove advantageous.

Lysine demethylase LSD1 is associated with stemness in EBV-positive B cell lymphoma.

EBV-infected lymphoma has a poor prognosis and various treatment strategies are being explored. Reports suggesting that B cell lymphoma can be induced by epigenetic regulation have piqued interest in studying mechanisms targeting epigenetic regulation. Here, we set out to identify an epigenetic regulator drug that acts synergistically with doxorubicin in EBV-positive lymphoma. We expressed the major EBV protein, LMP1, in B-cell lymphoma cell lines and used them to screen 100 epigenetic modifiers in combination with doxorubicin. The screening results identified TCP, which is an inhibitor of LSD1. Further analyses revealed that LMP1 increased the activity of LSD1 to enhance stemness ability under doxorubicin treatment, as evidenced by colony-forming and ALDEFLUOR activity assays. Quantseq 3' mRNA sequencing analysis of potential targets regulated by LSD1 in modulating stemness revealed that the LMP1-induced upregulation of CHAC2 was decreased when LSD1 was inhibited by TCP or downregulated by siRNA. We further observed that SOX2 expression was altered in response to CHAC2 expression, suggesting that stemness is regulated. Collectively, these findings suggest that LSD1 inhibitors could serve as promising therapeutic candidates for EBV-positive lymphoma, potentially reducing stemness activity when combined with conventional drugs to offer an effective treatment approach.

Romidepsin Plus Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone Versus Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone in Patients With Previously Untreated Peripheral T-Cell Lymphoma: Final Analysis of the Ro-CHOP Trial.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.The primary analysis of the Ro-CHOP phase III randomized controlled trial (ClinicalTrials.gov identifier: NCT01796002) established that romidepsin (Ro) plus cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) did not yield an increased efficacy compared with CHOP alone as first-line treatment of peripheral T-cell lymphoma. We report the planned final analysis 5 years after the last patient enrolled. With a median follow-up of 6 years, median progression-free survival (PFS) was 12.0 months compared with 10.2 months (hazard ratio [HR], 0.79 [95% CI, 0.62 to 1.005]; P = .054), while median overall survival was 62.2 months (35.7-86.6 months) and 43.8 months (30.1-70.2 months; HR, 0.88 [95% CI, 0.68 to 1.14]; P = .324) in the Ro-CHOP and CHOP arms, respectively. In an exploratory analysis, the median PFS in the centrally reviewed follicular helper T-cell lymphoma subgroup was significantly longer in the Ro-CHOP arm (19.5 v 10.6 months, HR, 0.703 [95% CI, 0.502 to 0.985]; P = .039). Second-line treatments were given to 251 patients with a median PFS2 and OS2 after relapse or progression of 3.3 months and 11.5 months, respectively. Within the limits of highly heterogeneous second-line treatments, no specific regimen seemed to provide superior disease control. However, a potential benefit was observed with brentuximab vedotin in association with chemotherapy even after excluding anaplastic large-cell lymphoma subtype or after adjusting for histology and international prognostic index in a multivariate model (HR for PFS, 0.431 [95% CI, 0.238 to 0.779]; P = .005).

Mosunetuzumab Safety Profile in Patients With Relapsed/Refractory B-cell Non-Hodgkin Lymphoma: Clinical Management Experience From a Pivotal Phase I/II Trial.

BACKGROUND: Mosunetuzumab is a CD20xCD3 T-cell engaging bispecific antibody approved in Europe and the United States for relapsed/refractory (R/R) follicular lymphoma (FL) after ≥ 2 prior therapies. MATERIALS AND METHODS: We present interim safety data from the mosunetuzumab GO29781 (NCT02500407) phase I/II dose-escalation study in R/R non-Hodgkin lymphoma (NHL), focusing on FL. RESULTS: Overall, 218 patients with R/R NHL, including 90 with R/R FL, received a median of eight 21-day cycles of intravenous mosunetuzumab with step-up dosing in Cycle (C) 1 (C1 Day [D] 1, 1 mg; C1D8, 2 mg; C1D15/C2D1, 60 mg; C3D1 and onwards, 30 mg). Cytokine release syndrome (CRS) was the most common adverse event (AE), occurring in 39.4% (NHL) and 44.4% (FL) of patients. Events occurred predominantly during C1 at the first loading dose; the majority were grade 1/2. CRS events were managed at the investigator's discretion with supportive care, steroids, and tocilizumab, based on protocol management guidelines. Immune effector cell-associated neurotoxicity syndrome was uncommon, reported in 0.9% (NHL) and 1.1% (FL) of patients. Neutropenia occurred in 27.5% (NHL) and 28.9% (FL) of patients (mostly grade 3/4) and could be effectively managed using granulocyte colony-stimulating factor. Tumor lysis syndrome occurred in 0.9% (NHL) and 1.1% (FL) of patients (all grade 3/4 with CRS; all resolved). CONCLUSION: Mosunetuzumab monotherapy as treatment for R/R B-cell NHL, including FL, was associated with low rates of severe AEs (including CRS) and is suitable for outpatient administration in the community setting. Adapted protocol guidance for the management of select AEs during mosunetuzumab treatment is included.

Feasibility of Circulating Tumor DNA Analysis in Patients with Follicular Lymphoma.

PURPOSE: The feasibility of sequencing circulating tumor DNA (ctDNA) in plasma as a biomarker to predict early relapse or poor prognosis in patients with follicular lymphoma (FL) receiving systemic immunochemotherapy is not clear. MATERIALS AND METHODS: We sequenced DNA from cell-free plasma that was serially obtained from newly diagnosed FL patients undergoing systemic immunochemotherapy. The mutation profiles of ctDNA at the time of diagnosis and at response evaluation and relapse and/or progression were compared with clinical course and treatment outcomes. RESULTS: Forty samples from patients receiving rituximab-containing immunochemotherapy were analyzed. Baseline sequencing detected mutations in all cases, with the major detected mutations being KMT2C (50%), CREBBP (45%), and KMT2D (45%). The concentration of ctDNA and tumor mutation burden showed a significant association with survival outcome. In particular, the presence of mutations in CREBBP and TP53 showed poor prognosis compared with patients without them. Longitudinal analysis of ctDNA using serially collected plasma samples showed an association between persistence or reappearance of ctDNA mutations and disease relapse or progression. CONCLUSION: Analysis of ctDNA mutations in plasma at diagnosis might help predict outcome of disease, while analysis during follow-up may help to monitor disease status of patients with advanced FL. However, the feasibility of ctDNA measurement must be improved in order for it to become an appropriate and clinically relevant test in FL patients.

Immune profiling of patients with extranodal natural killer/T cell lymphoma treated with daratumumab.

Natural killer/T cell lymphoma (NKTCL) is a highly aggressive, heterogeneous non-Hodgkin lymphoma resulting from malignant proliferation of cytotoxic natural killer (NK) or T cells. Previous studies demonstrated variable expression of CD38 on NKTCL tumors. Daratumumab, a human IgGκ monoclonal antibody targeting CD38 with a direct on-tumor and immunomodulatory mechanism of action, was hypothesized to be a novel therapeutic option for patients with relapsed or refractory (R/R) NKTCL. In the phase 2 NKT2001 study (ClinicalTrials.gov Identifier: NCT02927925) assessing the safety and efficacy of daratumumab, a suboptimal overall response rate was seen in R/R NKTCL patients. One patient, whose tumors did not express CD38, responded to treatment, suggesting that the immunomodulatory activities of daratumumab may be sufficient to confer clinical benefit. To understand the suboptimal response rate and short duration of response, we investigated the immune profile of NKTCL patients from NKT2001 in the context of daratumumab anti-tumor activity. Tumor tissue and whole blood were, respectively, analyzed for CD38 expression and patient immune landscapes, which were assessed via cytometry by time-of-flight (CyTOF), multiparameter flow cytometry (MPFC), clonal sequencing, and plasma Epstein-Barr virus (EBV)-DNA level measurements. Changes observed in the immune profiles of NKTCL patients from NKT2001, including differences in B and T cell populations between responders and nonresponders, suggest that modulation of the immune environment is crucial for daratumumab anti-tumor activities in NKTCL. In conclusion, these findings highlight that the clinical benefit of daratumumab in NKTCL may be enriched by B/T cell-related biomarkers.

KLRG1 Cell Depletion as a Novel Therapeutic Strategy in Patients with Mature T-Cell Lymphoma Subtypes.

PURPOSE: Develop a novel therapeutic strategy for patients with subtypes of mature T-cell and NK-cell neoplasms. EXPERIMENTAL DESIGN: Primary specimens, cell lines, patient-derived xenograft models, commercially available, and proprietary anti-KLRG1 antibodies were used for screening, target, and functional validation. RESULTS: Here we demonstrate that surface KLRG1 is highly expressed on tumor cells in subsets of patients with extranodal NK/T-cell lymphoma (ENKTCL), T-prolymphocytic leukemia (T-PLL), and gamma/delta T-cell lymphoma (G/D TCL). The majority of the CD8+/CD57+ or CD3-/CD56+ leukemic cells derived from patients with T- and NK-large granular lymphocytic leukemia (T-LGLL and NK-LGLL), respectively, expressed surface KLRG1. The humanized afucosylated anti-KLRG1 monoclonal antibody (mAb208) optimized for mouse in vivo use depleted KLRG1+ TCL cells by mechanisms of ADCC, ADCP, and CDC rather than apoptosis. mAb208 induced ADCC and ADCP of T-LGLL patient-derived CD8+/CD57+ cells ex vivo. mAb208 effected ADCC of subsets of healthy donor-derived KLRG1+ NK, CD4+, CD8+ Tem, and TemRA cells while sparing KLRG1- naïve and CD8+ Tcm cells. Treatment of cell line and TCL patient-derived xenografts with mAb208 or anti-CD47 mAb alone and in combination with the PI3K-δ/γ inhibitor duvelisib extended survival. The depletion of macrophages in vivo antagonized mAb208 efficacy. CONCLUSIONS: Our findings suggest the potential benefit of a broader treatment strategy combining therapeutic antibodies with PI3Ki for the treatment of patients with mature T-cell and NK-cell neoplasms. See related commentary by Varma and Diefenbach, p. 2300.