Antibiotic-induced loss of gut microbiome metabolic output correlates with clinical responses to CAR T-cell therapy.

Antibiotic-induced microbiome dysbiosis is widespread in oncology, adversely affecting outcomes and side effects of various cancer treatments, including immune checkpoint inhibitors and chimeric antigen receptor T (CAR-T) cell therapies. In this study, we observed that prior exposure to broad-spectrum ABX with extended anaerobic coverage like piperacillin-tazobactam and meropenem was associated with worsened anti-CD19 CAR-T therapy survival outcomes in large B-cell lymphoma patients (n=422), compared to other ABX classes. In a discovery subset of these patients (n=67), we found that the use of these ABX was in turn associated with substantial dysbiosis of gut microbiome function, resulting in significant alterations of the gut and blood metabolome, including microbial effectors such as short-chain fatty acids (SCFAs) and other anionic metabolites, findings that were largely reproduced in an external validation cohort (n=58). Broader evaluation of circulating microbial metabolites revealed reductions in indole and cresol derivatives, as well as trimethylamine N-oxide, in patients who received ABX treatment (discovery n=40, validation n=28). These findings were recapitulated in an immune-competent CAR-T mouse model, where meropenem-induced dysbiosis led to a systemic dysmetabolome and decreased murine anti-CD19 CAR-T efficacy. Furthermore, we demonstrate that SCFAs can enhance the metabolic fitness of CAR-T cells, leading to improved tumor killing capacity. Together, these results suggest that broad-spectrum ABX deplete metabolically active commensals whose metabolites are essential for enhancing CAR-T efficacy, shedding light on the intricate relationship between ABX exposure, microbiome function and their impact on CAR-T cell efficacy. This highlights the potential for modulating the microbiome to augment CAR-T immunotherapy.

Characterization of lymphopenia and correlating the risk of cytopenias with dose and BM volume irradiated in aggressive B-cell lymphoma patients bridged with radiation therapy for CAR-T cell therapy.

INTRODUCTION: The impact of bridging radiation therapy (bRT) for CAR T-cell therapy on absolute lymphocyte count (ALC) kinetics and treatment outcome is unknown. METHODS: We retrospectively reviewed adults with relapsed/refractory aggressive large B-cell lymphoma (LBCL) who received bRT prior to CD-19 CAR-T between 11/2017-4/2023. The change in ALC (ALC Δ RT) was computed by subtracting ALC pre- and post-bRT. Percent bone marrow (%BM) irradiated was calculated by estimating skeletal BM distribution. PFS, DSS, and OS were modeled via Kaplan-Meier. RESULTS: Fifty-one patients received bRT, of which 13 (25.5%) had bulky disease (≥7.5cm). The median bRT dose was 30Gy (range: 4-48Gy); 26 patients (51%) received ≥30Gy. Thirty-one patients (61%) received bRT comprehensively to all disease sites. The median cumulative %BM irradiated was 5.05% (range: 0-50%). At a median follow-up of 10.3 months (95% CI: 7.7-16.4), the 1-year OS, PFS, and DSS rates were 80% (95% CI: 66-99), 78% (64-87), and 82% (68-90), respectively. The incidence of ≥Grade 3 lymphopenia was 33% pre-RT and 68% post-RT, but recovered to 43% at the conditioning chemotherapy (CC) timepoint. There was no correlation between post-RT Grade ≥3 lymphopenia and the receipt of comprehensive bRT, combined modality bridging, ≥30Gy bRT, or bRT to ≥15% of BM (all p>0.2). Among patients with Grade 0-2 lymphopenia pre-RT, increased conversion to Grade ≥3 lymphopenia post-RT correlated with comprehensive or ≥30Gy bRT, but these factors did not impair ALC recovery at CC. There was no association between ALC Δ RT or post-RT ALC with 30 or 90 day response (p>0.25), DSS, PFS, or OS (p>0.3). CONCLUSIONS: Lymphocyte change during bRT is not associated with CAR-T outcomes. Persistent cytopenia risk following bRT is not associated with bRT to ≥30Gy, ≥15% of BM, or comprehensive coverage. While bRT can be delivered safely, we urge careful treatment planning when incorporating into pre-CAR-T regimens.

Outcomes and toxicities in patients with diffuse-large B cell lymphoma involving the gastrointestinal tract and digestive organs.

Background: Diffuse large B-cell lymphoma (DLBCL) involving the gastrointestinal (GI) organs is rare, and real-world outcomes after combined modality therapy (CMT) with systemic therapy (ST) and radiotherapy (RT) are not well-characterized, particularly in the contemporary era. We characterized outcomes in a large cohort of GI-DLBCL patients treated with ST alone or CMT. Methods: Patients with GI-DLBCL treated at a single institution were retrospectively reviewed. Kaplan-Meier and Cox regression models estimated survival. Multivariable analyses were conducted using the Cox proportional hazards model. Results: Of 204 patients, gastric involvement was most common (63%). Most presented with early-stage disease (61%). All patients received ST and 65 patients (32%) received RT, 88% as part of first-line CMT. Median dose was 36 Gy (IQR 30.6-39.6) in 18 fractions (IQR 17-22). Median follow-up was 46 months. Five-year overall survival (OS) and progression-free survival (PFS) was 88% and 84%, respectively; complete response (CR) rate was 82%. Improved OS associated with low IPI (p=0.001), fewer chemotherapy lines (p<0.001), early stage (p<0.006), and CR (p<0.001). Survival did not differ by RT receipt (p>0.25). Only early stage and CR correlated with improved OS on multivariable analysis. Stomach-directed RT vs. RT to other sites correlated with improved PFS and OS (p<0.04). Patients with early stage DLBCL treated with CMT in the post-rituximab era had equivalent OS vs. ST alone, even with fewer chemotherapy cycles (p<0.02; median of 4 with RT vs. 6 cycles without). Fifty patients had bulky disease (≥7.5 cm), of whom 18 (36%) had early stage disease. Among patients with bulky disease, 5 (10%) developed relapse at the initial site of disease bulk. Four of the 5 patients did not receive consolidative radiation. Among these 4 patients, 3 relapsed only in their initial site of bulky disease. Of 191 patients with luminal GI-DLBCL, n=4 (2.1%) developed perforation; only one received RT. Acute Grade 3 toxicities were reported in 41.2% of patients, and 12 (5.8%) patients had late Grade 3 toxicities, 99% attributed to chemotherapy. Conclusion: GI-DLBCL patients have favorable outcomes after CMT with minimal late toxicity. CMT may be offered with abridged systemic regimens with equivalent outcomes. Stomach directed-RT may mitigate relapse risk associated with incomplete disease response or bulky disease.

Safety and activity of lenalidomide in combination with obinutuzumab in patients with relapsed indolent non-Hodgkin lymphoma: a single group, open-label, phase 1/2 trial.

Background: Rituximab and lenalidomide is a preferred option for relapsed indolent B cell non-Hodgkin lymphoma. Obinutuzumab may be a superior combination partner with lenalidomide given enhanced antibody dependent cellular cytotoxicity and phagocytosis compared to rituximab. Our aim was to determine the recommended phase 2 dose, safety, and activity of lenalidomide in combination with fixed dose of obinutuzumab in relapsed and refractory indolent B cell non-Hodgkin lymphoma. Methods: In this single-arm, open-label, phase 1/2 trial, we enrolled patients with relapsed or refractory WHO Grade 1-3A follicular lymphoma, marginal zone lymphoma and small lymphocytic lymphoma and adequate performance status (ECOG 0-2) at the MD Anderson Cancer Center. We excluded patients with evidence of ongoing transformation to aggressive lymphoma. During phase 1, 1000 mg intravenous obinutuzumab was administered with three predefined levels of oral lenalidomide in a 3 + 3 dose escalation design to establish lenalidomide 20 mg as the recommended phase 2 dose. During phase 2, patients received induction therapy with six 28-day cycles of lenalidomide 20 mg with intravenous obinutuzumab 1000 mg. In accordance with our prior experience with lenalidomide plus rituximab, patients who were responding to the combination could receive up to 6 additional cycles (up to 12 cycles in total) of combination therapy. Dosing of obinutuzumab was continued in all responding patients after cycle 6 every 2 months for a total of 30 months from the start of therapy. The decision of number of cycles of combination therapy beyond 6 was at discretion of the investigator and was included to allow individualisation of therapy to maximise response while minimising exposure. The co-primary objectives were to evaluate the safety and overall response, defined as the proportion of patients who achieved a complete or partial response in relapsed and refractory indolent non-Hodgkin lymphoma at the end of induction therapy, according to Cheson and colleagues (2007 criteria). The secondary endpoints were complete response after induction therapy and time to event endpoints including time to progression, progression free survival, and overall survival. Analyses were intent to treat in the efficacy cohort and per-treated in the safety population in all patients who received at least one dose of either investigational agent. This trial is registered with ClinicalTrials.gov, NCT01995669. Findings: Between June 03, 2014, and 07 March 2019, we completed planned enrolment, and 66 patients started therapy including 9 patients in phase 1 and 57 patients in phase 2. All patients were evaluated for safety and the 60 patients treated at the recommended phase 2 dose of lenalidomide 20 mg were evaluable for activity. Grade 3-4 haematological toxicities included neutropenia 21% (14/66) and thrombocytopenia 11% (7/66) with no cases of febrile neutropenia. Grade 3-4 non-haematological toxicities included lung infection 8% (5/66), fatigue 8% (5/66) and rash 6% (4/66). By Cheson 2007 criteria, 90% (54/60, 95% CI: 79-96) achieved an overall response at the end of induction meeting the prespecified activity endpoint. Complete responses were seen in 33% (20/60, 95% CI: 22-47) at the end of induction. Median progression free survival, time to progression and overall survival have not been reached after median follow-up of 41.7 months. Estimated 4-year progression free survival rates were 55% (95% CI: 42-73), time to progression of 56% (95% CI: 43-74) and overall survival of 84% (95% CI: 74-95). Interpretation: Our findings suggest that oral lenalidomide with obinutuzumab is safe and highly active in patients with relapsed and refractory indolent B cell non-Hodgkin lymphoma and is associated with prolonged remission duration. The study is limited by the lack of a control arm leading to cross-trial comparisons to evaluate activity. Future randomised trials comparing this regime to rituximab and lenalidomide are warranted. Funding: Genentech and an MD Anderson Core grant.

Response-Adapted Ultralow-Dose Radiation Therapy for Orbital Indolent B-Cell Lymphoma: A Phase 2 Nonrandomized Controlled Trial.

Importance: Radiation therapy to doses of 24 to 36 Gy is currently used to treat indolent B-cell lymphoma of the ocular adnexa; however, ocular adverse effects are common. Objective: To determine if a response-adapted radiation therapy strategy will result in excellent disease outcomes while reducing orbital morbidity. Design, Setting, and Participants: This single-institution, phase 2 prospective nonrandomized controlled trial of a response-adapted strategy involved 50 evaluable patients with stage I to IV indolent B-cell lymphoma of the ocular adnexa enrolled between July 2015 and January 2021. This treatment approach was also retrospectively evaluated with a separate 55-patient cohort treated between March 2013 and October 2021. All data were analyzed between November 2021 and December 2023. Interventions: Patients were treated with ultralow-dose radiation therapy to 4 Gy in 2 fractions and assessed for response at 3-month intervals. Patients with persistent orbital lymphoma were offered an additional 20 Gy in 10 fractions to complete the response-adapted treatment. Main Outcome and Measures: The primary end point was 2-year local orbital control within the irradiated field after response-adapted therapy. Secondary end points included overall survival and complete response rate. Results: The 50 prospective patients were a median (range) of 63 (29-88) years old, and 31 (62%) were female. Among the 50 patients, 32 (64%) had mucosa-associated lymphoid tissue lymphoma, 12 (24%) had follicular lymphoma, and 6 (12%) had unclassifiable low-grade B-cell lymphoma. Thirty-one patients (62%) had stage I disease, and 36 (72%) were newly diagnosed. At a median follow-up of 37.4 (95% CI, 33.7-52.5) months, the 2-year local control rate was 89.4% (95% CI, 81.0%-98.7%), and the 2-year overall survival rate was 98.0% (95% CI, 94.1%-100%); 45 patients (90.0%; 95% CI, 78.2%-96.7%) experienced a complete response to response-adapted radiation, including 44 patients with a complete response to ultralow-dose radiation and 1 patient with a complete response after an additional 20 Gy. No local recurrences were observed among patients with a complete response to response-adapted therapy. No grade 3 or higher toxic effects were observed. In a planned subset analysis of 22 patients with newly diagnosed, untreated stage I mucosa-associated lymphoid tissue lymphoma, the 2-year local control rate was 90.7% (95% CI, 79.2%-100%), and the 2-year freedom from distant relapse rate was 95.2% (95% CI, 86.6%-100%). Conclusion and Relevance: In this nonrandomized controlled trial, response-adapted ultralow-dose therapy for indolent orbital B-cell lymphoma resulted in reduced radiation exposure, negligible toxic effects, and excellent disease outcomes. Trial Registration: ClinicalTrials.gov Identifier: NCT02494700.

Brentuximab vedotin plus cyclophosphamide, doxorubicin, etoposide, and prednisone followed by brentuximab vedotin consolidation in CD30-positive peripheral T-cell lymphomas: a multicentre, single-arm, phase 2 study.

BACKGROUND: CD30 expression is universal in anaplastic large-cell lymphoma and is expressed in some other peripheral T-cell lymphoma subtypes. Incorporation of brentuximab vedotin into initial therapy for people with CD30-positive peripheral T-cell lymphomas prolonged progression-free survival, but there is room for improvement, especially for people with non-anaplastic large-cell lymphoma subtypes. METHODS: We conducted a multicentre, international, single-arm, phase 2 trial to evaluate the safety and activity of CHEP-BV (cyclophosphamide, doxorubicin, prednisone, brentuximab vedotin, and etoposide) followed by brentuximab vedotin consolidation in patients with CD30-expressing peripheral T-cell lymphomas across five academic centres in the USA and Canada. Adults aged 18 years or older with newly diagnosed, untreated CD30-positive peripheral T-cell lymphomas, Eastern Cooperative Oncology Group score of 0-2, and adequate organ function were eligible to receive six planned cycles of CHEP-BV (ie, 1·8 mg/kg brentuximab vedotin intravenously on day 1, cyclophosphamide 750 mg/m2 intravenously on day 1, doxorubicin 50 mg/m2 intravenously on day 1, etoposide 100 mg/m2 daily intravenously on days 1-3, and prednisone 100 mg daily orally on days 1-5) with prophylactic G-CSF. Patients who responded to the treatment could receive brentuximab vedotin consolidation for up to ten additional cycles either after autologous haematopoietic stem-cell transplantation (HSCT) or directly after CHEP-BV. The primary endpoints were unacceptable toxicity during a 3-plus-3 safety lead-in in participants who received study treatment and completed the safety evaluation period (to confirm the recommended phase 2 dose of brentuximab vedotin in CHEP-BV) and the complete response rate after CHEP-BV induction therapy in participants who received study treatment and had response evaluation. The study was registered at ClinicalTrials.gov (NCT03113500), and this cohort completed the trial. The trial is ongoing with the enrolment of a new cohort. FINDINGS: 54 patients were screened for eligibility and 48 were eligible for the study. The participants (18 [38%] women and 30 [63%] men; 34 [71%] White, four [8%] Black, five [10%] Asian, ten [21%] Hispanic, and 37 [77%] non-Hispanic people) were recruited and enrolled between Dec 4, 2017, and June 14, 2021, and followed up until Aug 25, 2023, when the database was locked for analysis. 48 participants were evaluable for toxicity, and 47 were evaluable for response (one participant died from COVID-19 before response assessment). During the safety lead-in, one of six participants had an unacceptable toxicity (ie, platelet count <10 000 per mm3 in a participant with extensive bone marrow involvement), and the proposed phase 2 dose of 1·8 mg/kg brentuximab vedotin in CHEP-BV was confirmed. At completion of CHEP-BV, 37 of 47 participants had complete response, yielding a complete response rate of 79% (95% CI 64-89). The most common CHEP-BV-related toxicities of grade 3 or higher were neutropenia (14 [29%] of 48), leukopenia (11 [23%]), anaemia (ten [21%]), febrile neutropenia (ten [21%]), lymphopenia (nine [19%]), and thrombocytopenia (nine [19%]). There were no treatment-related deaths. INTERPRETATION: In patients with mostly CD30-expressing peripheral T-cell lymphomas other than non-anaplastic large-cell lymphoma, CHEP-BV (with or without autologous HSCT) followed by brentuximab vedotin consolidation was safe and active. FUNDING: SeaGen, Leukemia and Lymphoma Society, Lymphoma Research Foundation, and the National Cancer Institute of the National Institutes of Health.

Radiotherapy in the treatment of primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder.

BACKGROUND: Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder (PCSM-LPD) is an increasingly recognized entity with heterogeneous management strategies that may include radiotherapy. OBJECTIVE: Our aim was to characterize treatment options for PCSM-LPD, with a focus on the role of radiotherapy. METHODS: This is a retrospective review of 46 patients seen in the Cutaneous Lymphoma Program at the University of Texas MD Anderson Cancer Center, with a clinicopathologic review consistent with PCSM-LPD. All patients were biopsied and underwent observation, topical/intralesional steroids, and/or radiotherapy. Patients were confirmed to have residual disease prior to radiotherapy. RESULTS: All patients achieved a complete response (CR). Sixteen patients (35%) received focal radiotherapy, with a CR in 15 (94%). The CR rate following ultra-low-dose radiotherapy (4 Gy in 1-2 fractions) was 92%. There was no grade 3 toxicity after radiotherapy. Thirty patients were managed without radiotherapy, with excision and observation or steroids. CONCLUSION: Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder has excellent outcomes, and management strategies may include observation following biopsy, steroids, or radiation. Ultra-low-dose radiotherapy results in excellent outcomes with limited toxicity and is effective for persistent lesions after steroidal therapy.

Response-adapted ultra-low-dose 4 Gy radiation as definitive therapy of gastric MALT lymphoma: a single-centre, pilot trial.

BACKGROUND: Given the favourable prognosis of patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma, treatment-related toxicity should be minimised. We aimed to evaluate the efficacy of 4 Gy radiotherapy given in a response-adapted approach. METHODS: We conducted a single-centre, single-arm, prospective trial at MD Anderson Cancer Center (Houston, TX, USA) of response-adapted ultra-low-dose radiotherapy. Eligible patients were 18 years or older and had newly diagnosed or relapsed Helicobacter pylori-negative gastric MALT lymphoma, with stage I-IV disease. Given the expected low toxicity profile of treatment, performance status was not an exclusion criterion. Patients received external beam photon-based radiotherapy for a total dose of 4 Gy in two fractions. Patients with a complete response to 4 Gy via endoscopy and imaging at 3-4 months were observed; patients with a partial response were re-evaluated in 6-9 months. Residual disease at 9-13 months or stable or progressive disease at any time required additional treatment with 20 Gy. The primary endpoint was gastric complete response at 1 year (second evaluation timepoint) after 4 Gy treatment. All analyses were performed as intention to treat. This trial is registered at ClinicalTrials.gov (NCT03680586) and is complete and closed to enrolment. FINDINGS: Between March 27, 2019, and Oct 12, 2021, we enrolled 24 eligible patients. The median age of participants was 67 years (IQR 58-74; range 40-85); 15 (63%) were female and nine (37%) male; 18 (75%) were White, four (17%) Asian, and two (8%) Hispanic; 20 (83%) had stage I disease, one (4%) stage II, and three (13%) stage IV. Median follow-up time was 36 months (IQR 26-42). 20 patients (83%) had a complete response to 4 Gy (16 at 3-4 months, four at 9-13 months); two patients received 20 Gy for symptomatic stable disease at 3-4 months and two for residual disease at 9-13 months; all had a complete response. The 3-year local control rate was 96% (95% CI 88-100), with one local relapse at 14 months after 4 Gy radiotherapy salvaged successfully with 20 Gy. One patient with stage IV disease had a distant relapse. The most common adverse events were grade 1 nausea (nine [38%] of 24 patients who received 4 Gy and two [50%] of four patients who received 20 Gy) and grade 1 abdominal pain (five [21%] of 24 and zero of four, respectively). No grade 3 or worse adverse events were noted, including no treatment-related deaths. INTERPRETATION: Most patients had a complete response after 4 Gy radiotherapy; all who required an additional 20 Gy had a complete response within 12 months. This response-adapted strategy could be used to select patients who would benefit from additional radiotherapy and spare others potential associated toxicity. FUNDING: National Cancer Institute.

Native Aortic Valve Endocarditis Secondary to Gastric Antral Vascular Ectasia Manipulation During Endoscopic Argon Plasma Coagulation.

Gastric antral vascular ectasia (GAVE) is an uncommon cause of upper gastrointestinal (GI) bleeds. Due to the high vascularity of the region, transient bacteremia due to manipulation of the GI tract can very rarely cause the translocation of bacteria. We present a rare case in which endoscopic manipulation to treat GAVE led to native valve infective endocarditis (IE). Our patient had a prior history of GAVE and presented with worsening dizziness and shortness of breath (SOB). After an esophagogastroduodenoscopy (EGD) and subsequent argon plasma coagulation (APC) for active preantral bleeding, the patient was noted to have repeated fevers, a new cardiac murmur, and positive blood cultures for Staphylococcus epidermidis, leading to a diagnosis of native infective endocarditis. With high clinical suspicion and early recognition of a new cardiac murmur, a transesophageal echocardiogram (TEE) was key in identifying vegetation. This case highlights the importance of combining history, a physical exam, and diagnostic lab tests and imaging to identify endocarditis. Management included two months of intravenous (IV) vancomycin and repeat TEE for close monitoring of vegetation improvement.

Effect of delayed cell infusion in patients with large B-cell lymphoma treated with chimeric antigen receptor T-cell therapy.

Complications occurring after lymphodepleting chemotherapy (LDC) may delay chimeric antigen receptor (CAR) T-cell infusion. The effect of these delays on clinical outcomes is unclear. We performed a retrospective analysis of 240 patients with relapsed/refractory large B-cell lymphoma treated with standard-of-care axicabtagene ciloleucel (axi-cel) and identified 40 patients (16.7%) who had delay in axi-cel infusion. Of these, 85% had delay due to infection. At time of LDC initiation, patients with delayed infusion had lower absolute neutrophil count (p=0.006), lower platelets (p=0.004), lower hemoglobin (p5 days (4.6 vs. 8.2 months; p=0.036), but not 1 day (5.7 vs. 8.2 months; p=0.238). Following propensity score matching, patients with delayed infusion continued to have shorter median PFS (3.5 vs. 6.0 months; p=0.015). Levels of proinflammatory cytokines on day of infusion were significantly higher in patients with delayed infusion. Together, these findings suggest that delays in CAR T-cell administration after initiation of LDC are associated with inferior outcomes. Further studies are needed to guide strategies to improve efficacy in such patients.

Capnocytophaga canimorsus Infection in a 38-Year-Old Male after a Dog Bite.

Here, we present a unique case of a 38-year-old male with a history of alcohol use disorder and multiple sexual partners, who presented with fulminant sepsis with shock, multiorgan failure, and livedo racemosa after a dog bite the week prior. The patient was intubated on arrival and was started on vasopressors and antibiotics. Eventually, the patient's clinical status improved, and he was transferred out of the intensive care unit. Blood cultures tested positive for oxidase-positive Gram-negative rods two days after collection, and species identification showed Capnocytophaga canimorsus.

Prolonged cytopenia following CD19 CAR T cell therapy is linked with bone marrow infiltration of clonally expanded IFNγ-expressing CD8 T cells.

Autologous anti-CD19 chimeric antigen receptor T cell (CAR T) therapy is highly effective in relapsed/refractory large B cell lymphoma (rrLBCL) but is associated with toxicities that delay recovery. While the biological mechanisms of cytokine release syndrome and neurotoxicity have been investigated, the pathophysiology is poorly understood for prolonged cytopenia, defined as grade ≥3 cytopenia lasting beyond 30 days after CAR T infusion. We performed single-cell RNA sequencing of bone marrow samples from healthy donors and rrLBCL patients with or without prolonged cytopenia and identified significantly increased frequencies of clonally expanded CX3CR1hi cytotoxic T cells, expressing high interferon (IFN)-γ and cytokine signaling gene sets, associated with prolonged cytopenia. In line with this, we found that hematopoietic stem cells from these patients expressed IFN-γ response signatures. IFN-γ deregulates hematopoietic stem cell self-renewal and differentiation and can be targeted with thrombopoietin agonists or IFN-γ-neutralizing antibodies, highlighting a potential mechanism-based approach for the treatment of CAR T-associated prolonged cytopenia.

Impact of cumulative dose of brentuximab vedotin on outcomes of frontline therapy for advanced-stage Hodgkin lymphoma.

In the pivotal study ECHELON-1, brentuximab vedotin (BV), doxorubicin, vinblastine, and dacarbazine (A + AVD) demonstrated superior efficacy compared with bleomycin + AVD for the treatment of advanced-stage classic Hodgkin lymphoma (cHL). However, there are minimal available data regarding the frequency of dose reductions or omission of BV during curative therapy and the potential impact on patient outcomes. In a real-world analysis, we retrospectively reviewed the characteristics and outcomes of 179 patients with stage III or IV cHL treated with frontline A + AVD from January 2010 to April 2022. Treatment consisted of up to 1.2 mg/kg of BV and standard dose AVD IV on days 1 and 15 of each 28-day cycle for up to 6 cycles. At the time of treatment, the median patient age was 37 years, and a high-risk International Prognostic Score was observed in 46% of patients. Overall, 91% of patients received 6 cycles of AVD; 55% of patients did not receive the intended cumulative dose of BV (CDB); 28% of patients received two-thirds or less than the planned CDB. At a median follow-up time of 27.4 months (95% confidence interval [CI], 24.8-29), the median progression-free survival (PFS) was not reached, and the 12-month PFS was 90.3% (95% CI, 85.9-95.0). The impact of CDB on PFS was not significant (P = .15), nor was high CDB significantly associated with increased adverse events. In real-world experience, A + AVD is a highly effective treatment for patients with advanced-stage cHL, including for patients with prominent dose reductions of BV.

Safety of Concurrent Radiation Therapy With Brentuximab Vedotin in the Treatment of Lymphoma.

Purpose: Purpose: Radiation therapy (RT) and the antibody-drug conjugate brentuximab vedotin (BV) are standard-of-care treatment options for patients with certain B and T-cell lymphomas; however, there are limited data exploring the safety of concurrent BV and RT (BVRT). Methods and Materials: We performed a single institutional retrospective review of 44 patients who received BVRT. Results: Twenty percent of patients (9/44) developed new grade 2 or higher (G2+) hematologic toxicity (HT) after BVRT, which was associated with radiation dose (median dose of 35 Gy in those with new G2+ HT compared with 15 Gy in those without; P < .001). Acute G2+ elevation in aspartate transaminase or alanine transaminase level was associated with administration of concurrent chemotherapy with BVRT (57% vs 21%; P = .047) but was not associated with any RT factors. Local control (LC) was achieved in 24 of 42 patients (57%) with available follow-up. Ten patients (23%) proceeded to stem cell transplant or cellular therapy after BVRT at a median of 48 days (interquartile range, 27-188 days). At last follow-up, 10 patients (23%) remained without evidence of disease. Conclusions: Our analysis demonstrates that the combination of BV and RT is well tolerated, though care should be taken during RT planning to reduce the risk of HT. This combination can be considered for patients in need of both local and systemic disease control.

PD-L1+ macrophages are associated with favorable features in primary mediastinal (thymic) large B-cell lymphoma.

Primary mediastinal (thymic) large B-cell lymphoma (PMBCL) is a rare, aggressive subtype of non-Hodgkin lymphoma and has a complex inflammatory microenvironment. Although most patients can be cured with standard-of-care immunochemotherapy, patients who have disease relapse have an unfavorable prognosis. Pre-treatment prognostic biomarkers in PMBCL are needed. In this retrospective study, we analyzed the clinical features and outcomes of PMBCL patients and their association with immune cell subpopulations identified by multiplex immunofluorescence at initial diagnosis. Two different antibody panels were used to assess macrophages in tissue biopsy specimens collected before the initiation of induction therapy. Twelve PMBCL patients, including five patients who had disease relapse, were included in the analysis. At a median follow-up time of 32.2 months, the median progression-free and overall survival durations were not reached. Our findings suggest that a high density of PD-L1+ macrophages is associated with favorable features, such as early disease stage and the absence of B-symptoms, and indicate that a high percentage of PD-L1+ macrophages and high densities of CD30+PD-L1+ cells and CD30+ cells might be associated with a lower risk of relapse within 12 months of therapy initiation. Further studies are needed to develop a biomarker signature predictive of treatment response with therapeutic consequences for patients with newly diagnosed PMBCL.

A non-antibiotic-disrupted gut microbiome is associated with clinical responses to CD19-CAR-T cell cancer immunotherapy.

Increasing evidence suggests that the gut microbiome may modulate the efficacy of cancer immunotherapy. In a B cell lymphoma patient cohort from five centers in Germany and the United States (Germany, n = 66; United States, n = 106; total, n = 172), we demonstrate that wide-spectrum antibiotics treatment ('high-risk antibiotics') prior to CD19-targeted chimeric antigen receptor (CAR)-T cell therapy is associated with adverse outcomes, but this effect is likely to be confounded by an increased pretreatment tumor burden and systemic inflammation in patients pretreated with high-risk antibiotics. To resolve this confounding effect and gain insights into antibiotics-masked microbiome signals impacting CAR-T efficacy, we focused on the high-risk antibiotics non-exposed patient population. Indeed, in these patients, significant correlations were noted between pre-CAR-T infusion Bifidobacterium longum and microbiome-encoded peptidoglycan biosynthesis, and CAR-T treatment-associated 6-month survival or lymphoma progression. Furthermore, predictive pre-CAR-T treatment microbiome-based machine learning algorithms trained on the high-risk antibiotics non-exposed German cohort and validated by the respective US cohort robustly segregated long-term responders from non-responders. Bacteroides, Ruminococcus, Eubacterium and Akkermansia were most important in determining CAR-T responsiveness, with Akkermansia also being associated with pre-infusion peripheral T cell levels in these patients. Collectively, we identify conserved microbiome features across clinical and geographical variations, which may enable cross-cohort microbiome-based predictions of outcomes in CAR-T cell immunotherapy.