Tafasitamab for the treatment of patients with diffuse large B-cell lymphoma

Patients with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) require additional treatments, especially those not eligible or not responding to high dose cytotoxic chemotherapy and stem cell transplantation. Over the last few years, several new treatments have been developed and approved for these patients, among them of particular relevance are those targeting CD19. Tafasitamab is a humanized monoclonal antibody targeting CD19, composed of a modified fragment crystallizable (Fc) region engineered with higher affinity for Fc gamma receptors (FcγR) receptors, leading to increased cytotoxicity through natural killer cells and macrophages (antibody-dependent cellular cytotoxicity and antibody-dependent cell-mediated phagocytosis). In this product review, we will discuss its mechanism of action, safety profile and efficacy results from clinical trials that led to its approval in combination with lenalidomide for patients with R/R DLBCL ineligible for high-dose chemotherapy and autologous transplantation.

RE-MIND2: comparative effectiveness of tafasitamab plus lenalidomide versus polatuzumab vedotin/bendamustine/rituximab (pola-BR), CAR-T therapies, and lenalidomide/rituximab (R2) based on real-world data in patients with relapsed/refractory diffuse large B-cell lymphoma

RE-MIND2 (NCT04697160) compared patient outcomes from the L-MIND (NCT02399085) trial of tafasitamab+lenalidomide with those of patients treated with other therapies for relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) who are autologous stem cell transplant ineligible. We present outcomes data for three pre-specified treatments not assessed in the primary analysis. Data were retrospectively collected from sites in North America, Europe, and the Asia Pacific region. Patients were aged ≥18 years with histologically confirmed DLBCL and received ≥2 systemic therapies for DLBCL (including ≥1 anti-CD20 therapy). Patients enrolled in the observational and L-MIND cohorts were matched using propensity score-based 1:1 nearest-neighbor matching, balanced for six covariates. Tafasitamab+lenalidomide was compared with polatuzumab vedotin+bendamustine+rituximab (pola-BR), rituximab+lenalidomide (R2), and CD19-chimeric antigen receptor T-cell (CAR-T) therapies. The primary endpoint was overall survival (OS). Secondary endpoints included treatment response and progression-free survival. From 200 sites, 3,454 patients were enrolled in the observational cohort. Strictly matched patient pairs consisted of tafasitamab+lenalidomide versus pola-BR (n = 24 pairs), versus R2 (n = 33 pairs), and versus CAR-T therapies (n = 37 pairs). A significant OS benefit was observed with tafasitamab+lenalidomide versus pola-BR (HR: 0.441; p = 0.034) and R2 (HR: 0.435; p = 0.012). Comparable OS was observed in tafasitamab+lenalidomide and CAR-T cohorts (HR: 0.953, p = 0.892). Tafasitamab+lenalidomide appeared to improve survival outcomes versus pola-BR and R2, and comparable outcomes were observed versus CAR-T. Although based on limited patient numbers, these data may help to contextualize emerging therapies for R/R DLBCL. CLINICAL TRIAL REGISTRATION: NCT04697160 (January 6, 2021).

Targeting CD19 for diffuse large B cell lymphoma in the era of CARs: Other modes of transportation

CD19 is nearly ubiquitously expressed on B-lymphocytes and in B-cell malignancies. Although CD19-directed CAR T cells have greatly improved outcomes in B-cell malignancies, there are significant limitations with this therapy. CD19 can also be effectively targeted by other drug classes, such as monoclonal antibodies, antibody-drug conjugates, and bispecific T cell engagers or antibodies. However, the optimal patient selection and sequencing of these novel therapies has not yet been established. In this review, we discuss the utilization of CD19 as a target for the treatment of DLBCL, focusing on tafasitamab, loncastuximab tesirine, and blinatumomab. We provide a comprehensive review of the pivotal clinical trials, discussing the strength and limitations of the data for each agent. We explore the emerging evidence that CD19 expression is retained following exposure to these agents and that patients can be successfully re-challenged with anti-CD19 therapies of a different drug class upon disease relapse post-CAR T cells. Finally, we discuss how these drugs potentially fit into the most current treatment paradigm for DLBCL.

Tafasitamab and lenalidomide for relapsed/refractory diffuse large B-cell lymphoma in a patient on chronic intermittent hemodialysis

INTRODUCTION

Tafasitamab is an anti-CD19 monoclonal antibody indicated for the treatment of relapsed/refractory diffuse large B-cell lymphoma to be given in combination with lenalidomide. Experiences with tafasitamab in the setting of hemodialysis are limited and the efficacy and safety of this agent in this setting are unknown.

CASE REPORT

We describe a patient with relapsed/refractory diffuse large B-cell lymphoma with hemodialysis-dependent end-stage renal disease who successfully received tafasitamab/lenalidomide.

MANAGEMENT AND OUTCOME

Tafasitamab and reduced dose lenalidomide were initiated for relapsed diffuse large B-cell lymphoma. Tafasitamab was administered on non-dialysis days. Follow-up imaging for disease response assessment demonstrated a complete response. Therapy was well tolerated; the only major toxicity experienced was grade 4 neutropenia that resolved with dose adjustment to lenalidomide. Over a year from initiating therapy, the patient remains in a complete response.

DISCUSSION/CONCLUSION

The combination of tafasitamab and dose-reduced lenalidomide produced a complete response in the treatment of relapsed/refractory diffuse large B-cell lymphoma in the setting of chronic intermittent hemodialysis.

Tafasitamab Plus Lenalidomide Versus 3 Rituximab-Based Treatments for Non-Transplant Eligible Relapsed/Refractory Diffuse Large B-Cell Lymphoma: A Matching-Adjusted Indirect Comparison

Introduction

Tafasitamab plus lenalidomide (TAFA + LEN) received accelerated US Food and Drug Administration approval and conditional European Medicines Agency approval for treatment of adults with relapsed or refractory diffuse large B-cell lymphoma (R/R DLBCL) not eligible for autologous stem cell transplant. This study investigates the relative efficacy of TAFA + LEN versus comparator treatments.

Methods

Matching-adjusted indirect comparisons (MAICs) of TAFA + LEN were performed using data from L-MIND, and comparator studies assessing rituximab-based combination therapies, including polatuzumab vedotin + bendamustine + rituximab (POLA + BR) bendamustine + rituximab (BR), and gemcitabine + oxaliplatin + rituximab (R-GEMOX) to provide relative efficacy estimates for overall survival (OS), progression-free survival (PFS), duration of response (DOR), objective response rate (ORR), and complete response rate (CRR). Patient-level data from L-MIND were weighted to match reported distributions of clinically validated prognostic factors and effect modifiers in comparator trials. MAIC results versus multiple BR studies were pooled using meta-analysis.

Results

MAICs were feasible versus POLA + BR and BR. Compared to POLA + BR, TAFA + LEN was associated with significantly longer DOR [hazard ratio (HR) 0.34 (95% CI 0.12, 0.98); p = 0.045]. Due to concerns about the proportional hazard assumption for OS and PFS, separate HRs were estimated before and after 4 months of follow-up. OS after 4 months, was significantly greater for TAFA + LEN versus POLA + BR [HR 0.41 (95% CI 0.19, 0.90); p = 0.026]. Compared with BR, TAFA + LEN was associated with significantly improved OS [GO29365 comparator trial: HR 0.39 (95% CI 0.18, 0.82); p = 0.014], PFS (pooled data: HR 0.39 (95% CI 0.29, 0.53); p < 0.001], DOR [pooled data: HR 0.35 (95% CI 0.25, 0.50); p < 0.001], and CRR [pooled data: odds ratio 2.43 (95% CI 1.33, 4.41); p = 0.004].

Conclusion

In MAIC analyses, treatment with TAFA + LEN for R/R DLBCL provided better OS and PFS outcomes than standard treatment regimens. Validation from large, randomized, phase 3 clinical trials is required to confirm these results.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02094-5.

Tafasitamab in combination with lenalidomide has been recently approved for the treatment of adults with relapsed or refractory diffuse large B-cell lymphoma. There are no clinical trials to directly compare the outcomes of tafasitamab + lenalidomide against other treatments for diffuse large B-cell lymphoma. Matching-adjusted indirect comparisons allow an estimate of the relative efficacy of treatments to be derived in the absence of head-to-head comparisons from clinical trials. Matching-adjusted indirect comparisons analyses utilizing data from previously published clinical trials were conducted to compare the combination of tafasitamab + lenalidomide against 3 standard treatments for relapsed or refractory diffuse large B-cell lymphoma: polatuzumab vedotin + bendamustine + rituximab, bendamustine + rituximab, and rituximab + gemcitabine + oxaliplatin. Compared to those treated with polatuzumab vedotin + bendamustine + rituximab, patients treated with TAFA + LEN maintained their response to treatment for longer and are more likely to experience long-term survival. When compared to those treated with bendamustine + rituximab, patients treated with TAFA + LEN had increased survival, a higher level of response, and maintained their response to treatment for longer. Overall, the findings suggest that treatment with TAFA + LEN for R/R DLBCL is likely to result in significantly better outcomes compared with standard rituximab-based treatments.

Tafasitamab mediates killing of B-cell non-Hodgkin's lymphoma in combination with γδ T cell or allogeneic NK cell therapy

Tafasitamab is an Fc-modified monoclonal antibody that binds to CD19, a cell-surface antigen that is broadly expressed on various types of B-cell non-Hodgkin’s lymphoma (NHL). Antibody-dependent cellular cytotoxicity (ADCC), a key mode of action of tafasitamab, is mediated through the binding of tafasitamab’s Fc region to FcγRIIIa receptors on immune effector cells and results in antitumor activity. Despite the proven clinical activity of tafasitamab in combination with lenalidomide in the treatment of diffuse large B-cell lymphoma (DLBCL), a higher number of immune cells in cancer patients may improve the activity of tafasitamab. Here, we characterized two ex vivo-expanded FcγRIIIa receptor—expressing cell types—γδ T and MG4101 natural killer (NK) cells—as effector cells for tafasitamab in vitro, and found that in the presence of these cells tafasitamab was able to induce ADCC against a range of NHL cell lines and patient-derived cells. We also explored the concept of effector cell supplementation during tafasitamab treatment in vivo by coadministering MG4101 NK cells in Raji and Ramos xenograft models of NHL. Combination treatment of tafasitamab and allogeneic MG4101 NK cells in these models demonstrated a survival benefit compared with tafasitamab or MG4101 monotherapy (Raji: 1.7- to 1.9-fold increase in lifespan; Ramos: 2.0- to 4.1-fold increase in lifespan). In conclusion, adoptive cell transfer of ex vivo-expanded allogeneic NK or autologous γδ T cells in combination with tafasitamab treatment may potentially be a promising novel approach to increase the number of immune effector cells and enhance the antitumor effect of tafasitamab.

Tafasitamab for refractory/relapsed diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is a common lymphoproliferative and invasive disease. The current first-line regimen for the treatment of DLBCL is R-CHOP, which is the combination of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone. R-CHOP has significantly improved the outcome of DLBCL in the last decades. However, 30-40% of patients fail the therapy with R-CHOP. Salvage chemotherapy for relapsed/refractory DLBCL (R/R DLBCL) is extremely challenging, especially in elderly patients. In July 2020, a new monoclonal antibody, tafasitamab, was approved by the Food and Drug Administration (FDA) of the United States for the treatment of DLBCL. Tafasitamab is an anti-CD19 monoclonal antibody which is Fc-enhanced and humanized. CD19 is typically expressed in the developing B cells in non-Hodgkin's lymphomas. Tafasitamab has been proven to be a safe and valid treatment and recommended to be used in combination with lenalidomide in adults with R/R DLBCL who are ineligible for autologous stem cell transplantation (ASCT). This article evaluates the pharmacodynamics, pharmacokinetics, mechanism of action and the clinical application of tafasitamab in the treatment of DLBCL, particularly in R/R DLBCL. The advantages and disadvantages of using tafasitamab and chimeric antigen receptor T cells (CAR-T cells) targeting CD19 are also discussed.

Anti-CD19 CAR T-cell therapy remission despite prior anti-CD19 antibody Tafasitamab in relapsed/refractory DLBCL

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Disease progression following anti-CD19 monoclonal antibody Tafasitamab treatment should not preclude subsequent anti-CD19 CART-cell therapy.

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Previous studies have demonstrated sequential anti-CD19 to be effective.

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Larger studies among R/R DLBCL patients across anti-CD19 modalities are needed to guide sequencing of therapies following initial anti-CD19 therapy.

Tafasitamab (MOR208) is an Fc-enhanced, humanized, monoclonal antibody that targets CD19. The L-MIND (NCT02399085) trial, an open-label, single-arm, phase II study of Tafasitamab (TAFA) plus lenalidomide (LEN), reported progression-free survival of 16 months in R/R DLBCL patients ineligible for autologous stem cell transplantation. Despite recent advances in anti-CD19 therapy, no clinical evidence exists to direct the sequencing of CAR T cell therapy following relapse after prior anti-CD19 therapy. We present the first published case of TAFA/LEN treatment followed by CAR T therapy with sustained remission. Disease progression following treatment with Tafasitamab may not preclude patients from CAR T cell therapy.

Challenges and Opportunities in the Management of Diffuse Large B-Cell Lymphoma in Older Patients

Most patients with diffuse large B-cell lymphoma (DLBCL) are diagnosed at age 60 years or older. Challenges to effective therapy among older individuals include unfavorable biologic features of DLBCL, geriatric vulnerabilities, suboptimal treatment selection, and toxicities of cytotoxic chemotherapy. Wider application of geriatric assessments may help identify fit older patients who benefit from standard immunochemotherapy without unnecessary dose reductions. Conversely, attenuated regimens may provide a better balance of risk and benefit for selected unfit or frail patients. Supportive care with the use of corticosteroid-based prephase, prophylactic growth factors, and early institution of supportive and palliative care can help maximize treatment tolerance. Several novel or emerging therapies have demonstrated favorable toxicity profiles, thus facilitating effective treatment for elderly patients. In the relapsed or refractory setting, patients who are not candidates for stem cell transplantation can benefit from newly approved options including polatuzumab vedotin-based combinations or tafasitamab plus lenalidomide, which may have higher efficacy and/or lower toxicity than historical chemotherapy regimens. Chimeric antigen receptor T-cell therapy has been successfully applied to older patients outside of clinical trials. In the first-line setting, emerging immunotherapy options (bispecific antibodies) and targeted therapies (anti-CD20 antibodies combined with lenalidomide and/or B-cell receptor inhibitors) may provide chemotherapy-free approaches for DLBCL. Enrolling older patients in clinical trials will be paramount to fully examine potential efficacy and toxicity of these strategies. In this review, we discuss recent advances in fitness stratification and therapy that have expanded curative options for older patients, as well as future opportunities to improve outcomes in this population. IMPLICATIONS FOR PRACTICE: Management of diffuse large B-cell lymphoma in older patients poses challenges due to aggressive disease biology and geriatric vulnerability. Although R-CHOP remains standard first-line treatment, geriatric assessment may help evaluate patients' fitness for immunochemotherapy. Corticosteroid prephase, prophylactic growth factors, and early palliative care can improve tolerance of treatment. Novel salvage options (polatuzumab vedotin-based combinations, tafasitamab plus lenalidomide) or chimeric antigen receptor T-cell therapy should be considered in the relapsed or refractory setting for patients ineligible for stem cell transplantation. Emerging immunotherapies (bispecific antibodies) and targeted therapies provide potential first-line chemotherapy-free approaches, which need to be rigorously assessed in clinical trials that involve geriatric patients.