Polatuzumab vedotin-based salvage immunochemotherapy as third-line or beyond treatment for patients with diffuse large B-cell lymphoma: a real-world experience

Prognostic Factors and Effect Modifiers in Patients With Relapse or Refractory Diffuse Large B-Cell Lymphoma After Two Lines of Therapy: A Systematic Literature and Expert Clinical Review

OBJECTIVES

The objective of this systematic literature review (SLR) combined with expert clinical review was to identify and rank prognostic factors and effect measure modifiers (EMMs) systematically and comprehensively in patients with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) who initiate treatment after ≥ 2 prior lines of therapy (LoTs; 3L+ R/R DLBCL).

METHODS

We performed an SLR of studies published between 2016 and 2021 and extracted study characteristics, prognostic factors, and EMMs. This was followed by clinical review and ranking of findings by subject matter experts using questionnaires, follow-up interviews, and quantitative ranking.

RESULTS

Across 46 included studies, the SLR identified 36 prognostic factors significantly associated with ≥ 1 clinical outcome. Based on subject matter expert ranking of the SLR-derived list, the five most important prognostic variables in descending order are: early chemo-immunotherapy failure, Eastern Cooperative Oncology Group performance status, refractory to last LoT, number of prior LoTs, and double- or triple-hit lymphoma.

CONCLUSIONS

This SLR and expert clinical review is the first to provide a comprehensive assessment of prognostic factors for 3L+ R/R DLBCL. No statistically significant EMMs were identified. This robust multi-method approach can assist in selecting prognostic variables for comparative analyses between real-world studies and clinical trials.

Antibody-Drug Conjugates: The Toxicities and Adverse Effects That Emergency Physicians Must Know

Antibody-drug conjugates are novel antineoplastic agents whose use is expanding, both in terms of the number of drugs and the number of patients being treated. This article reviews the known toxicities and complications of antibody-drug conjugates that are currently approved for the treatment of cancer in the United States, with a focus on their emergency presentation and management. Similar to many other cancer therapies, most antibody-drug conjugates can cause diarrhea, nausea/vomiting, rash, peripheral neuropathy, and cytopenia, which are generally treated following standard-of-care. Interstitial lung disease, which may mimic pneumonia and cause respiratory failure and death, has been seen with trastuzumab deruxtecan and mirvetuximab soravtansine; emergency treatment of this condition includes oxygenation, ventilatory support, and corticosteroids. Inotuzumab ozogamicin and gemtuzumab ozogamicin are both associated with sinusoidal obstruction syndrome, a potentially fatal liver dysfunction that presents with weight gain, fluid overload, and jaundice. Abnormal liver function tests in patients who have been recently treated with these agents should be cautiously evaluated. Cardiac adverse events with antibody-drug conjugates are rare, but trastuzumab emtansine and trastuzumab deruxtecan may cause a decrease in cardiac contractility, and heart rate corrected QT interval prolongation is a rare effect of trastuzumab deruxtecan. Ocular adverse events, especially blurred vision, and keratopathy, are common with mirvetuximab soravtansine and tisotumab vedotin. Progressive multifocal leukoencephalopathy has been reported with brentuximab vedotin and polatuzumab vedotin. Tumor lysis syndrome may occur after treatment with gemtuzumab ozogamicin, polatuzumab vedotin, and brentuximab vedotin. Patients receiving enfortumab vedotin or brentuximab vedotin may develop hyperglycemia, sometimes presenting as diabetic ketoacidosis. Tisotumab vedotin and trastuzumab emtansine are associated with bleeding; although it is minor in most cases, severe bleeding and intracranial hemorrhage have occurred. Several antibody-drug conjugates can cause an anaphylactoid infusion-related reaction, which occurs most commonly during or soon after infusion but may be delayed up to 24 hours. Further research is needed to establish the real-world incidence of rare complications and how often patients with these complications present to the emergency department.

Pharmacovigilance analysis of polatuzumab plus bendamustine and rituximab treatment protocol: identifying comprehensive safety signals using FDA database

Background

The combination of polatuzumab, bendamustine and rituximab (pola+BR) was authorized for the treatment of relapsed or refractory Diffuse large B cell lymphoma (DLBCL). This study used the FDA database to identify safety signals related to the treatment protocol.

Methods

The adverse events (AEs) from 2019Q1 to 2023Q3 were analyzed by calculating the reporting odds ratio. Severe and non-severe cases were compared using either an independent samples t-test or chi-squared (χ2) test. Additionally, a score sheet was employed to prioritize the signals.

Results

In all database, 58 significant signals were detected within 1,597 patients accepting the treatment protocol. Common AEs like neutropenia, thrombocytopenia, and peripheral neuropathy, as well as other AEs like anaemia, sepsis, cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome (ICANS) were a major focus. In addtion, 51.7%, 45.6% and 1.7% were sorted into low, moderate and high priority in term of clinical importance, respectively. Unexpected significant signals included intestinal obstruction, epilepsy, deep vein thrombosis, haemorrhage, increased blood lactate dehydrogenase and hypercalcemia.

Conclusion

Our study identified significant AE signals for pola+BR through realworld disproportionality analysis data and analyzed the severity and clinical priority of these signals, which can assist clinicians in managing related AEs.

A real-world pharmacovigilance analysis of the FDA adverse event reporting system events for polatuzumab vedotin

BACKGROUND

Polatuzumab vedotin is the first antibody-drug conjugate approved by the US Food and Drug Administration (FDA) for patients with diffuse large B-cell lymphoma. This study evaluated adverse events (AEs) associated with polatuzumab vedotin by data mining of the FDA Adverse Event Reporting System (FAERS).

METHODS

This study included AEs registered in FAERS between 2019 Q2 and 2023 Q2. Four algorithms were used to quantify the signals of polatuzumab vedotin-associated AEs, including reporting odds ratio, proportional reporting ratio, Bayesian confidence propagation neural network, and multi-item gamma Poisson shrinker.

RESULTS

A total of 7,609,450 reports were collected from the FAERS database, and 1,388 reports of polatuzumab vedotin were identified as primary suspected AEs. Polatuzumab vedotin-associated AEs involved 26 organ systems. According to the four algorithms, 108 significant disproportionality AEs were retained simultaneously. Unexpected significant AEs included gastrointestinal hemorrhage, ileus, gastrointestinal perforation, cholecystitis, hypogammaglobulinemia, hepatitis B reactivation, hypercalcemia, hydronephrosis, cystitis hemorrhagic, interstitial lung disease, and thrombophlebitis. The median time to onset of polatuzumab vedotin-associated AEs was 20 (interquartile range 4-56) days.

CONCLUSIONS

Our study identified significant new AE signals for polatuzumab vedotin through real-world disproportionality analysis data and may provide additional evidence for risk identification of polatuzumab vedotin.

The potential of antibody-drug conjugates for effective therapy in diffuse large B-cell lymphoma

INTRODUCTION

Antibody-drug conjugates (ADCs) are a rapidly evolving class of anti-cancer drugs with a significant impact on management of hematological malignancies including diffuse large B-cell lymphoma (DLBCL). ADCs combine a cytotoxic drug (a.k.a. payload) attached through a linker to a monoclonal antibody specific to a particular cancer antigen. Payloads include microtubule disruptors or DNA damaging chemicals. After attaching to the antigen, the ADCs are internalized, and the payload is dissociated from ADC by lysozymes and delivered to the intended site for exerting cytotoxic effects. This unique molecular design permits a better balance of efficacy and safety. Loncastuximab tesirine and polatuzumab vedotin are two ADCs approved in the U.S.A. for treatment of DLBCL.

AREAS COVERED

This review covers the efficacy and safety data of these two drugs. We will review new ADC-based combination regimens and novel constructs in development.

EXPERT OPINION

ADCs have made a significant impact in improving outcomes of DLBCL patients. Both polatuzumab vedotin and loncastuximab tesirine are established as useful therapeutics options, with polatuzumab vedotin currently approved in first line and relapsed/refractory setting, while loncastuximab tesirine is approved in relapsed setting. ADCs are effective with tolerable safety profile and currently many more ADCs are undergoing clinical trials.

A real-world pharmacovigilance study of polatuzumab vedotin based on the FDA adverse event reporting system (FAERS)

Background

Polatuzumab vedotin, the first FDA-approved antibody-drug conjugate (ADC) targeting CD79b, is utilized in the treatment of previously untreated diffuse large B-cell lymphoma (DLBCL) or high-grade B-cell lymphoma (HGBL), as well as relapsed or refractory (R/R) DLBCL. Despite its approval, concerns persist regarding the long-term safety profile of polatuzumab vedotin. This study aims to evaluate the adverse events (AEs) associated with polatuzumab vedotin since its approval in 2019, utilizing data mining strategies applied to the FDA Adverse Event Reporting System (FAERS).

Methods

Signal detection employed four methodologies, including reporting odds ratio (ROR), proportional reporting ratio (PRR), bayesian confidence propagation neural network (BCPNN), and multi-item gamma poisson shrinker (MGPS), to evaluate and quantify the signals of polatuzumab vedotin-associated AEs. Additionally, subgroup analyses based on patients age, gender, and fatal cases were conducted to investigate AEs occurrences in specific subpopulations.

Results

A total of 1,521 reports listing polatuzumab vedotin as a "principal suspect (PS)" drug were collected from the FAERS database. Through concurrent compliance with four algorithms, 19 significant Standardized MedDRA Query (SMQ) AEs and 92 significant Preferred Term (PT) AEs were detected. Subgroup analyses revealed a higher incidence of PTs in male patients compared to female patients, increased likelihood of polatuzumab vedotin-associated AEs in elder patients (>65 years), and AEs with a high risk of fatal cases include: blood lactate dehydrogenase increased, cytopenia, and hydronephrosis. The median time to AEs occurrence following polatuzumab vedotin initiation was 18.5 (5∼57.75) days, with 95% of AEs occurred within 162 days.

Conclusion

This study identified various AEs associated with polatuzumab vedotin, offering critical insights for clinical monitoring and risk identification in patients receiving polatuzumab vedotin therapy.

Poor outcomes for trial-ineligible patients receiving polatuzumab for relapsed/refractory diffuse large B-cell lymphoma in routine care: An Australian Lymphoma and Related Diseases Registry project

Polatuzumab vedotin (Pola) is an approved therapy in combination with rituximab and bendamustine for relapsed or refractory diffuse large B-cell lymphoma (RR-DLBCL) based on positive results of the landmark phase II randomised G029365 trial. However, trial results for many approved novel therapies in RR-DLBCL have not been replicated in routine care cohorts, as RR-DLBCL patient populations are heterogeneous and trial eligibility is increasingly restrictive. We evaluated outcomes from pola ± bendamustine and rituximab in patients with RR-DLBCL enrolled in a compassionate access program with no alternative treatment options identified via the Australasian Lymphoma and Related Diseases Registry according to their eligibility for the original phase II published study. Of 58 eligible patients, 74% met the criteria deeming them ineligible for the G029365 original study at the time of pola's commencement. Median progression-free survival and overall survival in our cohort were 2.3 and 3.5 months, respectively. In contrast to the landmark trial cohort, more of our patients ceased therapy prior to completion, the majority due to progressive disease and only 8/58 received any subsequent treatment. Dismal outcomes in this Australian real-world population demonstrate trial eligibility is challenging to meet, and newer treatments can be difficult to deliver in routine care. Clinically applicable results from therapeutic studies require trial cohorts to reflect representative clinical populations wherever possible, and more research is required to address the benefit of novel agents in the increasing majority who are ineligible for modern studies.

Cell-of-origin effect of polatuzumab vedotin in diffuse large B-cell lymphoma: no ordinary subgroup analysis

ABSTRACT

Subgroup analysis from the POLARIX trial of polatuzumab vedotin plus chemotherapy for untreated large B-cell lymphoma suggests greater efficacy among patients with activated B-cell subtype disease. Both preclinical and additional clinical evidence support this interaction between cell-of-origin and polatuzumab efficacy.

The progress of novel strategies on immune-based therapy in relapsed or refractory diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) can be cured with standard front-line immunochemotherapy, whereas nearly 30-40% of patients experience refractory or relapse. For several decades, the standard treatment strategy for fit relapsed/refractory (R/R) DLBCL patients has been high-dose chemotherapy followed by autologous hematopoietic stem cell transplant (auto-SCT). However, the patients who failed in salvage treatment or those ineligible for subsequent auto-SCT have dismal outcomes. Several immune-based therapies have been developed, including monoclonal antibodies, antibody-drug conjugates, bispecific T-cell engaging antibodies, chimeric antigen receptor T-cells, immune checkpoint inhibitors, and novel small molecules. Meanwhile, allogeneic SCT and radiotherapy are still necessary for disease control for fit patients with certain conditions. In this review, to expand clinical treatment options, we summarize the recent progress of immune-related therapies and prospect the future indirections in patients with R/R DLBCL.

Autologous Transplantation May Still Effectively Treat Relapsed Diffuse Large B-Cell Lymphoma in Selected Patients

Treating relapsed and refractory diffuse large B-cell lymphoma is still challenging for clinicians, but the available CAR-T and bispecific antibodies have revolutionized therapy. Autologous stem cell transplantation was the most effective treatment modality previously. The authors reported data from a single center over ten years. The retrospective study included 116 patients, with 53 relapsed cases, 39 primary refractory cases, 19 who had CNS involvement, and 5 who had received primary consolidation transplants. The median duration of follow-up was 46 months. The median event-free survival was 75 months, and the median overall survival was 105 months for all cases. Five-year overall survival was 59%, and event-free survival was 54%. Pretreatment prognostic factors at diagnosis had no effect on the outcome of transplantation. The authors found no difference between survival in relapsed or refractory cases, and the number of salvage lines or the germinal center/activated B-cell type also did not influence the results. Complete metabolic response before transplantation confirmed by ¹⁸FDG PET/CT strongly affected survival. The pre-transplant creatinine and CRP levels significantly influenced the long-term outcome. The number of stem cells infused did not affect survival, but engraftment within nine days did result in a longer survival. These data support the finding that the response to salvage therapy did facilitate the identification of a better prognostic group who may still benefit from autologous transplantation.

Polatuzumab vedotin, rituximab, and bendamustine combination in relapsed or refractory diffuse large B-cell lymphoma: a real-world data from Turkey

Polatuzumab vedotin (Pola) with bendamustine and rituximab (BR) is a promising option for patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). We analyzed the data of 71 R/R DLBCL patients who had been treated with Pola-BR in the named patient program from March 2018 to April 2021 from 32 centers in Turkey. All patients received up to six cycles of Pola 1.8 mg/kg, rituximab 375 mg/m² on day 1, and bendamustine 90 mg/m² on days 1-2 of each cycle. Median age at Pola-BR initiation was 55 (19-84). The overall response rate was 47.9%, including 32.4% CR rate when a median of 3 cycles was applied. With a median follow-up of 5 months, the median OS was 5 months. Grade 3-4 neutropenia and thrombocytopenia were the most common hematological toxicities. The real-world data from our cohort showed the Pola-BR is an effective option with a manageable toxicity profile.

A multicenter retrospective study of polatuzumab vedotin in patients with large B-cell lymphoma after CAR T-cell therapy

Polatuzumab vedotin (PV) is an antibody-drug conjugate targeting CD79b that is approved for patients with relapsed/refractory large B-cell lymphoma (LBCL). Patients who relapse after chimeric antigen receptor (CAR) T-cell therapy were not included in the registration study, and reports of PV use after CAR T cells are limited. This multicenter retrospective analysis included patients with LBCL who relapsed or progressed after CAR T-cell therapy and subsequently received PV with or without rituximab and bendamustine between July 2019 and May 2021. Response to treatment and progression were assessed based on the 2014 Lugano criteria. Fifty-seven patients were included in the study: 18 (32%) patients were primary refractory to CAR T-cell therapy, and 34 (60%) patients received PV-based therapy immediately after CAR T-cell therapy. PV was combined with rituximab in 54 (95%) patients and administered with bendamustine in 35 (61%) patients. A response was achieved in 25 (44%) patients, including complete remission in 8 (14%). No significant association between baseline characteristics and response was observed. After a median follow-up of 47 weeks (95% confidence interval [CI], 40-54), 46 (81%) patients had disease progression or died, and the median progression-free survival was 10 weeks (95% CI, 5-15). On a multivariate analysis, bone marrow involvement (hazard ratio, 5.2; 95% CI, 1.8-15; P = .003) and elevated lactate dehydrogenase levels (hazard ratio, 5.0; 95% CI, 1.4-16; P = .01) were associated with shorter progression-free survival. Studies aimed at better characterizing the intrinsic mechanism of resistance and identifying optimal consolidation strategies for these patients are warranted.