Obinutuzumab in the treatment of B-cell malignancies: a comprehensive review

The type II anti-CD20 antibody obinutuzumab has structural and mechanistic features that distinguish it from the first anti-CD20 antibody, rituximab, which have translated into improved efficacy in phase III trials in indolent non-Hodgkin lymphoma and chronic lymphocytic leukemia (CLL). These gains have been shown through improvements in, and/or increased durability of, tumor response, and increases in progression-free survival in patients with CLL or follicular lymphoma (FL). Ongoing research is focusing on the use of biomarkers and the development of chemotherapy-free regimens involving obinutuzumab. phase II trials of such treatment regimens have shown promise for CLL, FL and mantle cell lymphoma, while phase III trials have highlighted obinutuzumab as the antibody partner of choice for novel agents in first-line CLL treatment.

Therapeutic roles of antibody drug conjugates (ADCs) in relapsed/refractory lymphomas

Relapsed or refractory lymphoma is commonly treated with combination chemoimmunotherapy and cellular immunotherapy. Modest response rates and associated toxicities are obstacles to achieving durable remission using traditional cytotoxic chemotherapy, especially in frail patients with advanced disease. Antibody drug conjugates represent a new class of novel targeted agents with significant improvement in therapeutic efficacy in the treatment of lymphomas. Several of these agents, which offer improved targeting, greater potency, and better therapeutic index over traditional chemotherapy, are changing the treatment landscape for lymphomas and other hematological malignancies. Despite the therapeutic potential of these agents, the delivery and release of cytotoxic agents to malignant cells through the combination of a monoclonal antibody, payload, and linker represents a complex design challenge. This article reviews the clinical data on currently available antibody drug conjugates and the ongoing development of novel antibody drug conjugates. Antibody drug conjugates constitute an important armamentarium for treatment of lymphomas and their evolving roles in the treatment spectrum are discussed.

Evolving therapeutic landscape in follicular lymphoma: a look at emerging and investigational therapies

Follicular Lymphoma (FL) is the most common subtype of indolent B cell non-Hodgkin lymphoma. The clinical course can be very heterogeneous with some patients being safely observed over many years without ever requiring treatment to other patients having more rapidly progressive disease requiring multiple lines of treatment for disease control. Front-line treatment of advanced FL has historically consisted of chemoimmunotherapy but has extended to immunomodulatory agents such as lenalidomide. In the relapsed setting, several exciting therapies that target the underlying biology and immune microenvironment have emerged, most notable among them include targeted therapies such as phosphoinositide-3 kinase and Enhancer of Zeste 2 Polycomb Repressive Complex 2 inhibitors and cellular therapies including chimeric antigen receptor T cells and bispecific T cell engagers. There are several combination therapies currently in clinical trials that appear promising. These therapies will likely reshape the treatment approach for patients with relapsed and refractory FL in the coming years. In this article, we provide a comprehensive review of the emerging and investigational therapies in FL and discuss how these agents will impact the therapeutic landscape in FL.

Follicular lymphoma: Update on management and emerging therapies at the dawn of the new decade

Follicular lymphoma is the most common indolent non-Hodgkin lymphoma. Survival has improved over the last several decades, mainly because of the incorporation of the anti-CD20 antibody rituximab into preexisting or rediscovered agents. The disease has a relapsing and remitting pattern, coupled with a risk of transformation into an aggressive lymphoma, and considered incurable for most patients. Next-generation sequencing technologies have increased our understanding of the biology and genetic landscape of the disease, identifying potential druggable targets for treatment. Current prognostic models cannot accurately identify patients at risk of early progression and despite the availability of treatment options for relapsed/refractory disease, rational treatment selection balancing disease control, efficacy with toxicity, and quality of life remain unmet needs. This review provides an overview of biology, prognostication, treatment options, and emerging therapies that provide valid grounds for optimism.

Polatuzumab Vedotin: First Global Approval

Polatuzumab vedotin (polatuzumab vedotin-piiq; Polivy™) is an antibody-drug conjugate comprising a monoclonal antibody against CD79b (a B cell receptor component) covalently conjugated to the anti-mitotic cytotoxic agent monomethyl auristatin (MMAE) via a cleavable linker. After binding to CD79b on the B-cell surface, polatuzumab vedotin is internalized and the linker is cleaved, releasing MMAE into the cell, where it inhibits division and induces apoptosis. Polatuzumab vedotin is being developed by Genentech (a subsidiary of Roche) for the treatment of haematological malignancies. In June 2019, the US FDA granted accelerated approval to polatuzumab vedotin, in combination with bendamustine plus rituximab, for the treatment of adults with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) who have received at least two prior therapies. Use of the compound in combination with bendamustine plus rituximab is also under regulatory review for relapsed/refractory DLBCL in the EU and is in ongoing phase 1b/2 development in this setting or relapsed/refractory follicular lymphoma (FL) in several countries. Various other polatuzumab vedotin combination therapy regimens are also in phase 1b/2 development for relapsed/refractory non-Hodgkin lymphoma (NHL) [including DLBCL and FL] or in phase 2 or 3 development for previously untreated DLBCL, while polatuzumab vedotin monotherapy has been in phase 1 development for relapsed/refractory B-cell NHL in Japan. This article summarizes the milestones in the development of polatuzumab vedotin leading to this first approval for its use in combination with bendamustine plus rituximab for relapsed/refractory DLBCL.