Therapeutic antibodies for mantle cell lymphoma: A brand-new era ahead

Treatment Landscape of Relapsed/Refractory Mantle Cell Lymphoma: An Updated Review

Mantle cell lymphoma (MCL) accounts for nearly 2-6% of all non-Hodgkin lymphoma (NHL) cases, with a steady incidence increase over the past few decades. Although many patients achieve an adequate response to the upfront treatment, the short duration of remission with rapid relapse is challenging during MCL management. In this regard, there is no consensus on the best treatment options for relapsed/refractory (R/R) disease, and the international guidelines demonstrate wide variations in the recommended approaches. The last decade has witnessed the introduction of new agents in the treatment landscape of R/R MCL. Since the introduction of Bruton's tyrosine kinase (BTK) inhibitors, the treatment algorithm and response of R/R MCL patients have dramatically changed. Nevertheless, BTK resistance is common, necessitating further investigations to develop novel agents with a more durable response. Novel agents targeting the B-cell receptor (BCR) signaling have exhibited clinical activity and a well-tolerable safety profile. However, as the responses to these novel agents are still modest in most clinical trials, combination strategies were investigated in pre-clinical and early clinical settings to determine whether the combination of novel agents would exhibit a better durable response than single agents. In this report, we provide an updated literature review that covers recent clinical data about the safety and efficacy of novel therapies for the management of R/R MCL.

Mantle cell lymphoma treatment options for elderly/unfit patients: A systematic review

Mantle cell lymphoma (MCL) is a rare B-cell non-Hodgkin lymphoma (NHL) that is aggressive and incurable with existing therapies, presenting a significant unmet clinical need. MCL occurs mainly in elderly patients with comorbidities; thus, intense treatment options including allogeneic stem cell transplantation (Allo-SCT) are not feasible. New treatment options are emerging for this elderly/unfit treatment group, we therefore conducted a systematic review to determine whether they offered an advance on the existing recommended treatment, R-CHOP. The search strategies to identify MCL therapies were designed to capture the most relevant studies from 2013 to 2020. Following preferred reporting items for systematic reviews and meta-analyses and population,interventions, observations and study design analysis, R-CHOP, ibrutinib and bendamustine plus rituximab (BR) were taken forward for critical and statistical analysis. All three therapies were effective in increasing the overall survival (OS) and progression-free survival of elderly/unfit patients with MCL. However, none resulted in a significant increase in OS compared to R-CHOP. In addition, R-CHOP had a better toxicity profile when compared to both ibrutinib and BR. We therefore conclude that treatment of elderly/unfit patients with MCL is still a significant unmet clinical need; and suggest that outside of the clinical trial setting, R-CHOP should remain the recommended front-line treatment for this patient group.

Anti-CD20 treatment for B-cell malignancies: current status and future directions

INTRODUCTION

The introduction of anti-CD20 monoclonal antibody therapy with rituximab in the 1990s greatly improved outcomes for patients with B-cell malignancies. Disease resistance or relapse after successful initial therapy and declining efficacy of subsequent rounds of treatment were the basis for the development of alternative anti-CD20-based antibody therapies.

AREAS COVERED

The novel anti-CD20 antibodies of atumumab, ublituximab, and obinutuzumab were developed to be differentiated via structural and mechanistic features over rituximab. We provide an overview of preclinical and clinical data, and demonstrate ways in which the pharmacodynamic properties of these novel agents translate into clinical benefit for patients.

EXPERT OPINION

Of the novel anti-CD20 antibodies, only obinutuzumab has shown consistently improved efficacy over rituximab in randomized pivotal trials in indolent non-Hodgkin lymphoma and chronic lymphocytic leukemia. The Phase 3 GALLIUM trial demonstrated significant improvements in progression-free survival with obinutuzumab-based immunochemotherapy over rituximab-based immunochemotherapy. Novel combinations of obinutuzumab, including with chemotherapy-free options are being explored, such as with the newly approved combinations of obinutuzumab with venetoclax, ibrutinib, or acalabrutinib. The biggest unmet need remains in the treatment of diffuse large B-cell lymphoma; emerging options in this field include the use of CAR-T cells and T-cell bispecific antibodies.

Mantle cell lymphoma: insights into therapeutic targets at the preclinical level

INTRODUCTION

Mantle cell lymphoma (MCL) is a chronically relapsing B-cell non-Hodgkin lymphoma characterized by recurrent molecular-cytogenetic aberrations that lead to deregulation of DNA damage response, cell cycle progression, epigenetics, apoptosis, proliferation, and motility. In the last 10 years, clinical approval of several innovative drugs dramatically changed the landscape of treatment options in the relapsed/refractory (R/R) MCL, which translated into significantly improved survival parameters.

AREAS COVERED

Here, up-to-date knowledge on the biology of MCL together with currently approved and clinically tested frontline and salvage therapies are reviewed. In addition, novel therapeutic targets in MCL based on the scientific reports published in Pubmed are discussed.

EXPERT OPINION

Bruton tyrosine-kinase inhibitors, NFkappaB inhibitors, BCL2 inhibitors, and immunomodulary agents in combination with monoclonal antibodies and genotoxic drugs have the potential to induce long-term remissions in majority of newly diagnosed MCL patients. Several other classes of anti-tumor drugs including phosphoinositole-3-kinase, cyclin-dependent kinase or DNA damage response kinase inhibitors have demonstrated promising anti-lymphoma efficacy in R/R MCL. Most importantly, adoptive immunotherapy with genetically modified T-cells carrying chimeric antigen receptor represents a potentially curative treatment approach even in the patients with chemotherapy and ibrutinib-refractory disease.