Ofatumumab maintenance versus observation in relapsed chronic lymphocytic leukaemia (PROLONG): an open-label, multicentre, randomised phase 3 study

Maintenance therapy for chronic lymphocytic leukaemia

BACKGROUND

Chronic lymphocytic leukaemia (CLL) is the most common lymphoproliferative disease in adults and currently remains incurable. As the progression-free period shortens after each successive treatment, strategies such as maintenance therapy are needed to improve the degree and duration of response to previous therapies. Monoclonal antibodies, immunomodulatory agents, and targeted therapies are among the available options for maintenance therapy. People with CLL who achieve remission after previous therapy may choose to undergo medical observation or maintenance therapy to deepen the response. Even though there is widespread use of therapeutic maintenance agents, the benefits and harms of these treatments are still uncertain.

OBJECTIVES

To assess the effects and safety of maintenance therapy, including anti-CD20 monoclonal antibody, immunomodulatory drug therapy, anti-CD52 monoclonal antibody, Bruton tyrosine kinase inhibitor, and B-cell lymphoma-2 tyrosine kinase inhibitor, for individuals with CLL.

SEARCH METHODS

We conducted a comprehensive literature search for randomised controlled trials (RCTs) with no language or publication status restrictions. We searched CENTRAL, MEDLINE, Embase, and three trials registers in January 2022 together with reference checking, citation searching, and contact with study authors to identify additional studies.

SELECTION CRITERIA

We included RCTs with prospective identification of participants. We excluded cluster-randomised trials, cross-over trial designs, and non-randomised studies. We included studies comparing maintenance therapies with placebo/observation or head-to-head comparisons.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. We assessed risk of bias in the included studies using Cochrane's RoB 1 tool for RCTs. We rated the certainty of evidence for the following outcomes using the GRADE approach: overall survival (OS), health-related quality of life (HRQoL), grade 3 and 4 adverse events (AEs), progression-free survival (PFS), treatment-related mortality (TRM), treatment discontinuation (TD), and all adverse events (AEs).

MAIN RESULTS

We identified 11 RCTs (2393 participants) that met the inclusion criteria, including seven trials comparing anti-CD20 monoclonal antibodies (mAbs) (rituximab or ofatumumab) with observation in 1679 participants; three trials comparing immunomodulatory drug (lenalidomide) with placebo/observation in 693 participants; and one trial comparing anti-CD 52 mAbs (alemtuzumab) with observation in 21 participants. No comparisons of novel small molecular inhibitors were found. The median age of participants was 54.1 to 71.7 years; 59.5% were males. The type of previous induction treatment, severity of disease, and baseline stage varied among the studies. Five trials included early-stage symptomatic patients, and three trials included advanced-stage patients (Rai stage III/IV or Binet stage B/C). Six trials reported a frequent occurrence of cytogenic aberrations at baseline (69.7% to 80.1%). The median follow-up duration was 12.4 to 73 months. The risk of selection bias in the included studies was unclear. We assessed overall risk of performance bias and detection bias as low risk for objective outcomes and high risk for subjective outcomes. Overall risk of attrition bias, reporting bias, and other bias was low. Anti-CD20 monoclonal antibodies (mAbs): rituximab or ofatumumab maintenance versus observation Anti-CD20 mAbs maintenance likely results in little to no difference in OS (hazard ratio (HR) 0.94, 95% confidence interval (CI) 0.73 to 1.20; 1152 participants; 3 studies; moderate-certainty evidence) and likely increases PFS significantly (HR 0.61, 95% CI 0.50 to 0.73; 1255 participants; 5 studies; moderate-certainty evidence) compared to observation alone. Anti-CD20 mAbs may result in: an increase in grade 3/4 AEs (rate ratio 1.34, 95% CI 1.06 to 1.71; 1284 participants; 5 studies; low-certainty evidence); little to no difference in TRM (risk ratio 0.82, 95% CI 0.39 to 1.71; 1189 participants; 4 studies; low-certainty evidence); a slight reduction to no difference in TD (risk ratio 0.93, 95% CI 0.72 to 1.20; 1321 participants; 6 studies; low-certainty evidence); and an increase in all AEs (rate ratio 1.23, 95% CI 1.03 to 1.47; 1321 participants; 6 studies; low-certainty evidence) compared to the observation group. One RCT reported that there may be no difference in HRQoL between the anti-CD20 mAbs (ofatumumab) maintenance and the observation group (mean difference -1.70, 95% CI -8.59 to 5.19; 480 participants; 1 study; low-certainty evidence). Immunomodulatory drug (IMiD): lenalidomide maintenance versus placebo/observation IMiD maintenance therapy likely results in little to no difference in OS (HR 0.91, 95% CI 0.61 to 1.35; 461 participants; 3 studies; moderate-certainty evidence) and likely results in a large increase in PFS (HR 0.37, 95% CI 0.19 to 0.73; 461 participants; 3 studies; moderate-certainty evidence) compared to placebo/observation. Regarding harms, IMiD maintenance therapy may result in an increase in grade 3/4 AEs (rate ratio 1.82, 95% CI 1.38 to 2.38; 400 participants; 2 studies; low-certainty evidence) and may result in a slight increase in TRM (risk ratio 1.22, 95% CI 0.35 to 4.29; 458 participants; 3 studies; low-certainty evidence) compared to placebo/observation. The evidence for the effect on TD compared to placebo is very uncertain (risk ratio 0.71, 95% CI 0.47 to 1.05; 400 participants; 2 studies; very low-certainty evidence). IMiD maintenance therapy probably increases all AEs slightly (rate ratio 1.41, 95% CI 1.28 to 1.54; 458 participants; 3 studies; moderate-certainty evidence) compared to placebo/observation. No studies assessed HRQoL. Anti-CD52 monoclonal antibodies (mAbs): alemtuzumab maintenance versus observation Maintenance with alemtuzumab may have little to no effect on PFS, but the evidence is very uncertain (HR 0.55, 95% CI 0.32 to 0.95; 21 participants; 1 study; very low-certainty evidence). We did not identify any study reporting the outcomes OS, HRQoL, grade 3/4 AEs, TRM, TD, or all AEs.

AUTHORS' CONCLUSIONS

There is currently moderate- to very low-certainty evidence available regarding the benefits and harms of maintenance therapy in people with CLL. Anti-CD20 mAbs maintenance improved PFS, but also increased grade 3/4 AEs and all AEs. IMiD maintenance had a large effect on PFS, but also increased grade 3/4 AEs. However, none of the above-mentioned maintenance interventions show differences in OS between the maintenance and control groups. The effects of alemtuzumab maintenance are uncertain, coupled with a warning for drug-related infectious toxicity. We found no studies evaluating other novel maintenance interventions, such as B-cell receptor inhibitors, B-cell leukaemia-2/lymphoma-2 inhibitors, or obinutuzumab.

Infections in patients with chronic lymphocytic leukemia

INTRODUCTION

Infection is a major complication in patients with chronic lymphocytic leukemia (CLL). Newly diagnosed patients are at high risk of developing infection caused by encapsulated bacteria, such as Streptococcus pneumoniae and Haemophylus influenzae.

METHOD AND RESULTS

However, once treatment is initiated, the spectrum of pathogens causing infection broadens, depending on the treatment regimens. With disease progression, cumulative immunosuppression occurs as a consequence of multiple treatment lines and the risk of infection further increases. On the other hand, the use of targeted therapies in the treatment of CLL have brought new risks of infection, with an increased incidence of invasive fungal diseases, particularly aspergillosis, in patients receiving Bruton kinase inhibitors.

CONCLUSION

In this article, we review the epidemiology of infection in patients with CLL, taking into account the treatment regimen, and briefly discuss the management of infection.

A review of prophylactic regimens to prevent invasive fungal infections in hematology patients undergoing chemotherapy or stem cell transplantation

INTRODUCTION

The recent introduction of targeted therapies, including monoclonal antibodies, tyrosine-kinase inhibitors, and immunotherapies has improved the cure rate of hematologic patients. The implication of personalized treatment on primary antifungal prophylaxis will be discussed.

AREAS COVERED

We reviewed the literature for clinical trials reporting the rate of invasive fungal infections during targeted and cellular therapies and stem cell transplant, and the most recent international guidelines for primary antifungal prophylaxis.

EXPERT OPINION

As the use of personalized therapies is growing, the risk of invasive fungal infection has emerged in various clinical settings. Therefore, it is possible that the use of mold-active antifungal prophylaxis would spread in the next years and the risk of breakthrough infections would increase. The introduction of new antifungal agents in the clinical armamentarium is expected to reduce clinical unmet needs concerning the management of primary antifungal prophylaxis and improve outcome of patients.

Measurable Residual Disease in Chronic Lymphocytic Leukemia: Current Understanding and Evolving Role in Clinical Practice

OPINION STATEMENT

Treatment of chronic lymphocytic leukemia (CLL) has evolved dramatically during the last decade, from chemoimmunotherapy (CIT)-based therapies to newer B-cell receptor (BCR) signaling targeting agents, which are sometimes given as continuous schemes. Response to treatment was traditionally defined according to clinical variables designed to assign a response category. Interest in assessing for deeper responses in CLL by the means of measurable residual disease (MRD) testing has been the subject of research during the last several years. Analyses and sub-analyses of clinical trials have shown that achieving undetectable MRD (uMRD) in CLL is an important prognostic factor. In this review, we summarize the available evidence about MRD in CLL, from the various assays available for measurement, the compartment to test, the impact of reaching uMRD according to the treatment regimen, and the results of fixed duration treatment guided by MRD trials. Finally, we summarize how MRD can be incorporated in clinical practice and how it may guide fixed duration treatment in the future should evidence continue to accumulate in that direction.

Ofatumumab regimens in chronic lymphocytic leukemia: a meta-analysis

Ofatumumab's therapeutic impact on patients with chronic lymphocytic leukemia (CLL) has been the subject of increasing clinical research. However, in recent years, no studies have yet provided a pooled assessment of the treatment effect of ofatumumab vs. non-ofatumumab regimens. Therefore, we conducted a progression meta-analysis to evaluate the efficacy of ofatumumab-based treatment in CLL patients using data from clinical studies. Relevant publications from PubMed, Web of Science and ClinicalTrials.gov were searched. The efficacy outcomes were progression-free survival (PFS) and overall survival (OS). The articles reviewed in the mentioned databases and matching the specified keywords were searched until January 2023. The pooled efficacy analysis showed that there was a significant difference in PFS [hazard ratios (HR) = 0.62, 95% confidence interval (CI) = 0.52-0.74] and no significant difference in OS (HR = 0.86, 95% CI = 0.71-1.03) between ofatumumab-based therapy and non-ofatumumab therapy. Our analysis showed the pooled efficacy for PFS was statistically significantly improved with ofatumumab-based treatments for CLL compared with other groups. Also, ofatumumab had no statistically significant improvement in the OS of patients with CLL. Thus, ofatumumab-based therapies for CLL patients could be improved by other combinational-based regimens.

Emerging Therapies in CLL in the Era of Precision Medicine

Over the past decade, the treatment landscape of CLL has vastly changed from the conventional FC (fludarabine and cyclophosphamide) and FCR (FC with rituximab) chemotherapies to targeted therapies, including inhibitors of Bruton tyrosine kinase (BTK) and phosphatidylinositol 3-kinase (PI3K) as well as inhibitors of BCL2. These treatment options dramatically improved clinical outcomes; however, not all patients respond well to these therapies, especially high-risk patients. Clinical trials of immune checkpoint inhibitors (PD-1, CTLA4) and chimeric antigen receptor T (CAR T) or NK (CAR NK) cell treatment have shown some efficacy; still, long-term outcomes and safety issues have yet to be determined. CLL remains an incurable disease. Thus, there are unmet needs to discover new molecular pathways with targeted or combination therapies to cure the disease. Large-scale genome-wide whole-exome and whole-genome sequencing studies have discovered genetic alterations associated with disease progression, refined the prognostic markers in CLL, identified mutations underlying drug resistance, and pointed out critical targets to treat the disease. More recently, transcriptome and proteome landscape characterization further stratified the disease and revealed novel therapeutic targets in CLL. In this review, we briefly summarize the past and present available single or combination therapies, focusing on potential emerging therapies to address the unmet clinical needs in CLL.

Agents contributing to secondary immunodeficiency development in patients with multiple myeloma, chronic lymphocytic leukemia and non-Hodgkin lymphoma: A systematic literature review

Introduction

Patients with hematological malignancies (HMs), like chronic lymphocytic leukemia (CLL), multiple myeloma (MM), and non-Hodgkin lymphoma (NHL), have a high risk of secondary immunodeficiency (SID), SID-related infections, and mortality. Here, we report the results of a systematic literature review on the potential association of various cancer regimens with infection rates, neutropenia, lymphocytopenia, or hypogammaglobulinemia, indicative of SID.

Methods

A systematic literature search was performed in 03/2022 using PubMed to search for clinical trials that mentioned in the title and/or abstract selected cancer (CLL, MM, or NHL) treatments covering 12 classes of drugs, including B-lineage monoclonal antibodies, CAR T therapies, proteasome inhibitors, kinase inhibitors, immunomodulators, antimetabolites, anti-tumor antibiotics, alkylating agents, Bcl-2 antagonists, histone deacetylase inhibitors, vinca alkaloids, and selective inhibitors of nuclear export. To be included, a publication had to report at least one of the following: percentages of patients with any grade and/or grade ≥3 infections, any grade and/or grade ≥3 neutropenia, or hypogammaglobulinemia. From the relevant publications, the percentages of patients with lymphocytopenia and specific types of infection (fungal, viral, bacterial, respiratory [upper or lower respiratory tract], bronchitis, pneumonia, urinary tract infection, skin, gastrointestinal, and sepsis) were collected.

Results

Of 89 relevant studies, 17, 38, and 34 included patients with CLL, MM, and NHL, respectively. In CLL, MM, and NHL, any grade infections were seen in 51.3%, 35.9% and 31.1% of patients, and any grade neutropenia in 36.3%, 36.4%, and 35.4% of patients, respectively. The highest proportion of patients with grade ≥3 infections across classes of drugs were: 41.0% in patients with MM treated with a B-lineage monoclonal antibody combination; and 29.9% and 38.0% of patients with CLL and NHL treated with a kinase inhibitor combination, respectively. In the limited studies, the mean percentage of patients with lymphocytopenia was 1.9%, 11.9%, and 38.6% in CLL, MM, and NHL, respectively. Two studies reported the proportion of patients with hypogammaglobulinemia: 0-15.3% in CLL and 5.9% in NHL (no studies reported hypogammaglobulinemia in MM).

Conclusion

This review highlights cancer treatments contributing to infections and neutropenia, potentially related to SID, and shows underreporting of hypogammaglobulinemia and lymphocytopenia before and during HM therapies.

Prognostic markers in patients with chronic lymphocytic leukaemia on targeted therapy, chemoimmunotherapy with anti-CD20 monoclonal antibody: a systematic review and meta-analysis of prognostic factors

Combination chemoimmunotherapy (CIT) consisting of anti-CD20 has improved the progression-free survival (PFS) and overall survival (OS) of patients with chronic lymphocytic leukaemia (CLL). We performed a comprehensive synthesis of prognostic factors in patients with CLL on combined CIT with anti-CD20 antibodies compared with standard chemotherapy alone or targeted therapy.We searched the MEDLINE and academic search complete electronic databases as well as clinicaltrials.gov (from inception up to 01 August 2022) for randomised controlled trials examining chemoimmunotherapy and targeted therapy in patients with CLL. The risk of bias and the quality of evidence was assessed using the quality in prognostic studies tool (QUIPS).A total of 10 prognostic factors were identified and evaluated in patients with CLL on anti-CD20 antibody-containing CIT. The predictive value of the following prognostic factors was confirmed and associated with poor patient outcomes; deletion 17p (HR = 3.39), Immunoglobulin heavy chain variable region gene mutation status (HR = 0.96) and β_2-microglobulin (HR = 1.41).Conventional predictive factors may have retained prognostic value and could be useful in the stratification of patients who may be non-responsive to CIT.Trial registration: International Prospective Register of Systematic Reviews (PROSPERO) registry (CRD42021218997).

Targeted therapies in CLL/SLL and the cumulative incidence of infection: A systematic review and meta-analysis

Background: Patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) are prone to infections.

Aims: Provide a pooled estimate of the cumulative incidence for infections that fulfilled the criteria associated with severe infectious adverse events for grade 3 or higher (including pneumonia, febrile neutropenia and sepsis) in patients who receive targeted therapies.

Methods: We searched PubMed and EMBASE for randomized controlled trials (RCT) that included patients with CLL/SLL who received targeted therapies and performed a random-effects meta-analysis to estimate the cumulative incidence of infections.

Results: Of 2,914 studies screened, we retrieved 31 which evaluated 11,660 patients. The pooled cumulative incidence of infections for patients who received treatment regimens based on a BTK inhibitors was 19.86%. For patients who received treatment based on rituximab and second generation anti-CD20 monoclonal antibodies, the pooled cumulative incidence of infections was 19.85 and 13.46%, respectively. Regarding PI3K inhibitor-based regimens the cumulative incidence of severe infections was 30.89%. BCL-2 inhibitors had a cumulative incidence of infections of 17.49% while lenalidomide and alemtuzumab had an incidence of 13.33 and 45.09%, respectively. The cumulative incidence of pneumonia ranged from 3.01 to 8.45% while febrile neutropenia ranged from 2.68 to 10.80%. Regarding sepsis, the cumulative incidence ranged from 0.9 to 4.48%.

Conclusion: Patients with CLL/SLL who receive targeted therapies may develop severe infections at significant rates that, in addition to disease stage and other complications, depend on the mechanism of action of the used drug. Surveillance for infections and development of effective prophylactic strategies are critical for patients with CLL/SLL who receive targeted therapies.

Systematic Review Registration: [https://systematicreview.gov/], identifier [registration number]

Phase 1 Study Evaluating Pharmacokinetics and Tolerability of Ofatumumab Combined With Bendamustine in Patients With Indolent B-Cell Non-Hodgkin's Lymphoma

The pharmacokinetics (PK) and safety of ofatumumab and bendamustine alone and in combination were evaluated in patients with treatment-naive or relapsed indolent B-cell non-Hodgkin lymphoma (iNHL). Patients were randomly assigned to ofatumumab and bendamustine or ofatumumab alone. Ofatumumab PK concentration profiles and parameters were similar, alone or in combination with bendamustine. A decrease of 14% in the maximum observed plasma concentration (C_max ) and 15% in the area under the plasma concentration-time curve (AUC) from time 0 to the last measurable concentration sampling time (AUC_last ) was observed for ofatumumab coadministered with bendamustine, which was not considered clinically relevant. Bendamustine PK concentration profiles and parameters were similar with or without ofatumumab. The most frequent treatment-related adverse event was infusion-related reaction in 53% in the combination arm and 47% in the ofatumumab arm. No relevant drug-drug interaction was observed between ofatumumab and bendamustine. Ofatumumab alone or in combination with bendamustine had a manageable safety profile.

Invasive Fungal Infections and Targeted Therapies in Hematological Malignancies

The use of targeted biologic therapies for hematological malignancies has greatly expanded in recent years. These agents act upon specific molecular pathways in order to target malignant cells but frequently have broader effects involving both innate and adaptive immunity. Patients with hematological malignancies have unique risk factors for infection, including immune dysregulation related to their underlying disease and sequelae of prior treatment regimens. Determining the individual risk of infection related to any novel agent is challenging in this setting. Invasive fungal infections (IFIs) represent one of the most morbid infectious complications observed in hematological malignancy. In recent years, growing evidence suggests that certain small molecule inhibitors, such as BTK inhibitors and PI3K inhibitors, may cause an increased risk of IFI in certain patients. It is imperative to better understand the impact that novel targeted therapies might have on the development of IFIs in this high-risk patient population.

The road to chemotherapy-free treatment in chronic lymphocytic leukaemia

PURPOSE OF REVIEW

The treatment landscape of chronic lymphocytic leukaemia (CLL) has tremendously evolved in the last decades, from chemo to chemoimmunotherapy (CIT) and, eventually, to pathway inhibitors that target critical pathways for leukaemic cells survival. Also, treatment goals are moving towards achieving undetectable minimal residual disease with little toxicity.

RECENT FINDINGS

We performed a thorough review of the history of treatment approvals by both the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). This review especially focuses on therapies that are currently approved by both agencies. The indications and particular characteristics of each drug are examined.

SUMMARY

Currently available treatment approaches for CLL offer the opportunity to individualize therapy for every single patient with CLL. Inhibitors of B-cell receptor (BCR) signalling pathways and antiapoptotic proteins are nowadays the treatment of choice for most CLL patients, but CIT can be an option for younger and fit patients with low-risk disease [mutated IGHV, no del(11q) or del(17p)/TP53 mutations].

Secondary Immunodeficiency and Risk of Infection Following Immune Therapies in Neurology

Secondary immunodeficiencies (SIDs) are acquired conditions that may occur as sequelae of immune therapy. In recent years a number of disease-modifying therapies (DMTs) has been approved for multiple sclerosis and related disorders such as neuromyelitis optica spectrum disorders, some of which are frequently also used in- or off-label to treat conditions such as chronic inflammatory demyelinating polyneuropathy (CIDP), myasthenia gravis, myositis, and encephalitis. In this review, we focus on currently available immune therapeutics in neurology to explore their specific modes of action that might contribute to SID, with particular emphasis on their potential to induce secondary antibody deficiency. Considering evidence from clinical trials as well as long-term observational studies related to the patients' immune status and risks of severe infections, we delineate long-term anti-CD20 therapy, with the greatest data availability for rituximab, as a major risk factor for the development of SID, particularly through secondary antibody deficiency. Alemtuzumab and cladribine have relevant effects on circulating B-cell counts; however, evidence for SID mediated by antibody deficiency appears limited and urgently warrants further systematic evaluation. To date, there has been no evidence suggesting that treatment with fingolimod, dimethyl fumarate, or natalizumab leads to antibody deficiency. Risk factors predisposing to development of SID include duration of therapy, increasing age, and pre-existing low immunoglobulin (Ig) levels. Prevention strategies of SID comprise awareness of risk factors, individualized treatment protocols, and vaccination concepts. Immune supplementation employing Ig replacement therapy might reduce morbidity and mortality associated with SIDs in neurological conditions. In light of the broad range of existing and emerging therapies, the potential for SID warrants urgent consideration among neurologists and other healthcare professionals.

The future of antibody therapy in chronic lymphocytic leukemia

INTRODUCTION

Outcomes in chronic lymphocytic leukemia (CLL) have been dramatically improved with the addition of anti-CD20 antibodies to chemotherapy, defining a new standard of care for many years. More recently, therapies targeting fundamental signaling and anti-apoptotic pathways within the CLL cell have demonstrated dramatic clinical responses, including in patients with high-risk prognostic markers, thus emerging as preferred therapy for many patients. While the addition of anti-CD20 antibodies to traditional chemotherapy resulted in significant improvements in outcomes, the role of monoclonal antibodies in the era of targeted agents remains an active area of investigation. Furthermore, since the advent of next-generation anti-CD20 antibodies, the role of specific anti-CD20 antibodies remains an open question.

AREAS COVERED

In this review, we highlight the important role that anti-CD20 antibody therapy has had in the field of CLL, both when used with chemotherapy and in combination with targeted therapy, as well as the current studies that are further exploring this treatment paradigm in the modern era.

EXPERT OPINION

While anti-CD20 antibodies have played a pivotal role in the treatment of CLL, additional studies will be required to determine the optimal application of these therapies in combination with targeted therapy.

A phase 3 randomized study (HOMER) of ofatumumab vs rituximab in iNHL relapsed after rituximab-containing therapy

Because of high relapse rates with rituximab combinations, there is an unmet need for new therapeutic agents for treatment of indolent B-cell non-Hodgkin lymphoma (iNHL) or follicular lymphoma (FL). In previous trials, ofatumumab in combination with chemotherapy showed good results in relapsed/refractory FL pretreated with rituximab. This phase 3 trial evaluated the efficacy and safety of single-agent ofatumumab vs single-agent rituximab in rituximab-sensitive relapsed FL that relapsed at least 6 months after completing the last prior treatment with single-agent rituximab or a rituximab-containing regimen. Patients were randomized 1:1 to receive either ofatumumab (1000 mg) or rituximab (375 mg/m2) every week for 4 weeks for the induction phase, followed by once every 2 months for 4 additional doses. The primary endpoint, progression-free survival (PFS) and secondary endpoints, overall response rate (ORR) and overall survival (OS), were evaluated. Overall, 438 patients were assigned to receive ofatumumab (n = 219) and rituximab (n = 219). Baseline characteristics were similar in both arms. The independent review committee assessed whether median PFS was shorter in the ofatumumab arm than in the rituximab arm (16.33 vs 21.29 months), with no significant difference (hazard ratio, 1.15; 95% confidence interval, 0.89-1.49; P = .29) and also showed a lower ORR (50%) compared with the rituximab arm (66%). At the time of analysis, data were not matured for OS results. The number of grade >3 adverse events was higher in the ofatumumab arm (37%) than the rituximab arm (28%). Ofatumumab showed no superiority over rituximab in patients with FL who had relapsed after a rituximab-containing therapy. This study was registered at www.clinicaltrials.gov as #NCT01200589.

Engaging the Innate and Adaptive Antitumor Immune Response in Lymphoma

Immunotherapy has emerged as a powerful therapeutic strategy for many malignancies, including lymphoma. As in solid tumors, early clinical trials have revealed that immunotherapy is not equally efficacious across all lymphoma subtypes. For example, immune checkpoint inhibition has a higher overall response rate and leads to more durable outcomes in Hodgkin lymphomas compared to non-Hodgkin lymphomas. These observations, combined with a growing understanding of tumor biology, have implicated the tumor microenvironment as a major determinant of treatment response and prognosis. Interactions between lymphoma cells and their microenvironment facilitate several mechanisms that impair the antitumor immune response, including loss of major histocompatibility complexes, expression of immunosuppressive ligands, secretion of immunosuppressive cytokines, and the recruitment, expansion, and skewing of suppressive cell populations. Accordingly, treatments to overcome these barriers are being rapidly developed and translated into clinical trials. This review will discuss the mechanisms of immune evasion, current avenues for optimizing the antitumor immune response, clinical successes and failures of lymphoma immunotherapy, and outstanding hurdles that remain to be addressed.

Herpesvirus Infections Potentiated by Biologics

Herpesviruses such as herpes simplex virus (HSV) type 1 and 2, varicella-zoster virus (VZV), and cytomegalovirus (CMV) maintain lifelong latency in the host after primary infection and can reactivate periodically either as asymptomatic viral shedding or as clinical disease. Immunosuppression, including biologic therapy, may increase frequency and severity of herpesvirus reactivation and infection. Licensed biologics are reviewed regarding their risks of potentiating HSV, VZV, and CMV reactivation and infection. Approaches to prophylaxis against HSV, VZV, and CMV infection or reactivation are discussed.

Invasive Fungal Diseases in Children with Hematological Malignancies Treated with Therapies That Target Cell Surface Antigens: Monoclonal Antibodies, Immune Checkpoint Inhibitors and CAR T-Cell Therapies

Since 1985 when the first agent targeting antigens on the surface of lymphocytes was approved (muromonab-CD3), a multitude of such therapies have been used in children with hematologic malignancies. A detailed literature review until January 2021 was conducted regarding pediatric patient populations treated with agents that target CD2 (alefacept), CD3 (bispecific T-cell engager [BiTE] blinatumomab), CD19 (denintuzumab mafodotin, B43, BiTEs blinatumomab and DT2219ARL, the immunotoxin combotox, and chimeric antigen receptor [CAR] T-cell therapies tisagenlecleucel and axicabtagene ciloleucel), CD20 (rituximab and biosimilars, 90Y-ibritumomab tiuxetan, ofatumumab, and obinutuzumab), CD22 (epratuzumab, inotuzumab ozogamicin, moxetumomab pasudotox, BiTE DT2219ARL, and the immunotoxin combotox), CD25 (basiliximab and inolimomab), CD30 (brentuximab vedotin and iratumumab), CD33 (gemtuzumab ozogamicin), CD38 (daratumumab and isatuximab), CD52 (alemtuzumab), CD66b (90Y-labelled BW 250/183), CD248 (ontuxizumab) and immune checkpoint inhibitors against CTLA-4 (CD152; abatacept, ipilimumab and tremelimumab) or with PD-1/PD-L1 blockade (CD279/CD274; atezolizumab, avelumab, camrelizumab, durvalumab, nivolumab and pembrolizumab). The aim of this narrative review is to describe treatment-related invasive fungal diseases (IFDs) of each category of agents. IFDs are very common in patients under blinatumomab, inotuzumab ozogamicin, basiliximab, gemtuzumab ozogamicin, alemtuzumab, and tisagenlecleucel and uncommon in patients treated with moxetumomab pasudotox, brentuximab vedotin, abatacept, ipilimumab, pembrolizumab and avelumab. Although this new era of precision medicine shows promising outcomes of targeted therapies in children with leukemia or lymphoma, the results of this review stress the necessity for ongoing surveillance and suggest the need for antifungal prophylaxis in cases where IFDs are very common complications.

Risk-adapted, ofatumumab-based chemoimmunotherapy and consolidation in treatment-naïve chronic lymphocytic leukemia: a phase 2 study

High-risk cytogenetics and minimal residual disease (MRD) after chemoimmunotherapy (CIT) predict unfavorable outcome in chronic lymphocytic leukemia (CLL). This phase 2 study investigated risk-adapted CIT in treatment-naïve CLL (NCT01145209). Patients with high-risk cytogenetics received induction with fludarabine, cyclophosphamide, and ofatumumab. Those without high-risk cytogenetics received fludarabine and ofatumumab. After induction, MRD positive (MRD+) patients received 4 doses of ofatumumab consolidation. MRD negative (MRD-) patients had no intervention. Of 28 evaluable for response, all responded to induction and 10 (36%) achieved MRD-. Two-year progression-free survival (PFS) was 71.4% (CI₉₅, 56.5-90.3%). There was no significant difference in median PFS between the high-risk and the standard-risk groups. Ofatumumab consolidation didn't convert MRD + to MRD-. In the MRD + group, we saw selective loss of CD20 antigens during therapy. In conclusion, risk-adapted CIT is feasible in treatment-naïve CLL. Ofatumumab consolidation didn't improve depth of response in MRD + patients. Loss of targetable CD20 likely reduces efficacy of consolidation therapy.

Ublituximab plus ibrutinib versus ibrutinib alone for patients with relapsed or refractory high-risk chronic lymphocytic leukaemia (GENUINE): a phase 3, multicentre, open-label, randomised trial

BACKGROUND

Patients with chronic lymphocytic leukaemia and high-risk features have poorer outcomes on ibrutinib than those without high-risk features. The aim of this study was to assess the benefit of adding ublituximab, an anti-CD20 monoclonal antibody, to ibrutinib therapy in this population.

METHODS

We did a randomised, phase 3, multicentre study (GENUINE) of patients aged 18 years or older with relapsed or refractory chronic lymphocytic leukaemia with at least one of 17p deletion, 11q deletion, or TP53 mutation, at 119 clinics in the USA and Israel. Eligible patients had received at least one previous chronic lymphocytic leukaemia therapy and had an Eastern Cooperative Oncology Group performance status of 2 or lower. We randomised patients (1:1) using permuted block randomisation with a block size of four and stratified by previous lines of therapy (one vs two or more) to receive ibrutinib alone or ibrutinib in combination with ublituximab. Treatment allocation was not masked to patients or investigators. Ibrutinib was given orally daily at 420 mg for all cycles. Ublituximab was given intravenously in 28-day cycles, with increasing doses during cycle 1 (≤150 mg on day 1, 750 mg on day 2, and 900 mg on days 8 and 15) and continuing at 900 mg on day 1 of cycles 2-6. After cycle 6, ublituximab was given at 900 mg every three cycles. The study was initially designed with co-primary endpoints of progression-free survival and overall response rate but due to protracted patient accrual, the protocol was amended to have a single primary endpoint of independent review committee-assessed overall response rate (defined as the proportion of patients who had a partial response, complete response, or complete response with incomplete marrow recovery according to the 2008 International Workshop on CLL criteria) in the intention-to-treat population. Safety was evaluated in the population of patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, NCT02301156, and the final analysis is presented.

FINDINGS

224 patients were assessed for eligibility, of whom 126 patients were enrolled and randomly assigned to receive ublituximab plus ibrutinib (n=64) or ibrutinib alone (n=62) between Feb 6, 2015, and Dec 19, 2016. After a median follow-up of 41·6 months (IQR 36·7-47·3), the overall response rate was 53 (83%) of 64 patients in the ublituximab plus ibrutinib group and 40 (65%) of 62 patients in the ibrutinib group (p=0·020). 117 patients, including 59 in the ublituximab plus ibrutinib group and 58 in the ibrutinib group, received at least one dose of treatment and were included in safety analyses. Most adverse events were grade 1 or 2. The most common grade 3 and 4 adverse events were neutropenia (11 [19%] patients in the ublituximab plus ibrutinib group and seven [12%] in the ibrutinib group), anaemia (five [8%] and five [9%]), and diarrhoea (six [10%] and three [5%]). The most common serious adverse events were pneumonia (six [10%] in the ublituximab plus ibrutinib group and four [7%] in the ibrutinib group), atrial fibrillation (four [7%] and one [2%]), sepsis (four [7%] and one [2%]), and febrile neutropenia (three [5%] and one [2%]). Two patients in the ublituximab plus ibrutinib group died due to adverse events (one cardiac arrest and one failure to thrive), neither of which were treatment-related. Five patients in the ibrutinib group died due to adverse events, including one cardiac arrest, one cerebral infarction, one intracranial haemorrhage, one Pneumocystis jirovecii pneumonia infection, and one unexplained death; the death due to cardiac arrest was considered to be treatment-related.

INTERPRETATION

The addition of ublituximab to ibrutinib resulted in a statistically higher overall response rate without affecting the safety profile of ibrutinib monotherapy in patients with relapsed or refractory high-risk chronic lymphocytic leukaemia. These findings provide support for the addition of ublituximab to Bruton tyrosine kinase inhibitors for the treatment of these patients.

FUNDING

TG Therapeutics.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of lymphoma

The recent development and clinical implementation of novel immunotherapies for the treatment of Hodgkin and non-Hodgkin lymphoma have improved patient outcomes across subgroups. The rapid introduction of immunotherapeutic agents into the clinic, however, has presented significant questions regarding optimal treatment scheduling around existing chemotherapy/radiation options, as well as a need for improved understanding of how to properly manage patients and recognize toxicities. To address these challenges, the Society for Immunotherapy of Cancer (SITC) convened a panel of experts in lymphoma to develop a clinical practice guideline for the education of healthcare professionals on various aspects of immunotherapeutic treatment. The panel discussed subjects including treatment scheduling, immune-related adverse events (irAEs), and the integration of immunotherapy and stem cell transplant to form recommendations to guide healthcare professionals treating patients with lymphoma.

Casting a wider protective net: Anti-infective vaccine strategies for patients with hematologic malignancy and blood and marrow transplantation

Patients who have hematologic malignancies are at high risk for infections but vaccinations may be effective prophylaxis. The increased infection risk derives from immune defects secondary to malignancy, the classic example being CLL, and chemotherapies and immunotherapy used to treat the malignancies. Therapy of hematologic malignancies is being revolutionized by introduction of novel targeted agents and immunomodulatory medications, improving the survival of patients. At the same time those agents uniquely change the infection risk and response to immunizations. This review will summarize current vaccine recommendations for patients with hematologic malignancies including patients who undergo hematopoietic cell transplant.

Pathogenesis of chronic lymphocytic leukemia and the development of novel therapeutic strategies

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in Western countries and is characterized by the clonal expansion of mature CD5⁺ B cells. There have been substantial advances in the field of CLL research in the last decade, including the identification of recurrent mutations, and clarification of clonal architectures, signaling molecules, and the multistep leukemogenic process, providing a comprehensive understanding of CLL pathogenesis. Furthermore, the development of therapeutic approaches, especially that of molecular target therapies against CLL, has markedly improved the standard of care for CLL. This review focuses on the recent insights made in CLL leukemogenesis and the development of novel therapeutic strategies.

Assessment of Hazard Ratios in Oncology Clinical Trials Terminated Early for Superiority: A Systematic Review

IMPORTANCE

Group sequential designs allow potential early trial termination at the interim analysis, before study completion. Traditional maximum likelihood estimate is commonly used to quantify the treatment effect in group sequential design trials; however, in published clinical trials, a bias-adjusted estimator has rarely been reported.

OBJECTIVE

To emphasize the need for considering overestimation of treatment effect by applying 2 bias-adjusted estimators to previously published, early-terminated oncology clinical trials.

EVIDENCE REVIEW

Trials published from 2013 to 2017 were identified by searching MEDLINE and Embase on February 23, 2018. This review was restricted to oncology clinical trials using group sequential designs with a single preplanned interim analysis as well as 2-arm randomized clinical trials that were subsequently stopped for efficacy reasons. Each article was independently reviewed by 3 biostatisticians during text screening, and differences in opinion were resolved by discussion. This report presents the unadjusted hazard ratio (HR) of an experimental arm to a reference arm and 2 bias-adjusted HRs calculated by using the conditional mean-adjusted estimator (CMAE) and weighted CMAE (WCMAE).

FINDINGS

In total, 198 abstracts were screened for eligibility, of which, 19 eligible clinical trials were identified as applicable to the bias-adjusted estimators. Unadjusted HRs ranged from 0.203 (95% CI, 0.150-0.276) to 0.71 (95% CI, 0.60-0.84), number of events at the interim analysis from 58 to 540, and information time from 48% to 82%. In each study, the HRs adjusted by CMAE and WCMAE were higher than the unadjusted HR. Bias-adjusted estimates in large trials (243 and 414 events at the interim analysis) were similar to the unadjusted HR. However, in small trials (eg, with 58 events at the interim analysis), bias-adjusted estimates were highly disparate from the unadjusted HR. In trials with large treatment effects (eg, HRs of 0.20 and 0.22), the difference between unadjusted and bias-adjusted HRs was small even though the number of events at the interim analysis was small; larger differences were observed when the unadjusted HR was greater than 0.5.

CONCLUSIONS AND RELEVANCE

In this systematic review of oncology clinical trials that were stopped for efficacy at the interim analysis, relatively large differences were noted between the unadjusted and adjusted HRs when the number of events at the interim analysis was small or when the unadjusted HR was close to the boundaries. These findings suggest presenting the 2 bias-adjusted HRs along with the unadjusted HR in the data monitoring committee meeting.

A comparison between the assessments of progression-free survival by local investigators versus blinded independent central reviews in phase III oncology trials

PURPOSE

In this study, we compared the assessments of progression-free survival (PFS) carried out by the local investigator or by a blinded independent central review in the framework of phase III registration randomized controlled trials (RCT) in oncology.

METHODS

We carried out a search in the clinicatrials.gov database, looking at the RCTs reporting the results of both independently assessed and investigator-assessed PFS. The hazard ratios (HRs) of investigator-assessed PFS and independently assessed PFS were recorded, and a discrepancy index was obtained by calculating the ratio of their respective HRs. Moreover, we investigated possible factors of discrepancy by analyzing the trials in different groups (by year, by tumor type, by drug type, by study design).

RESULTS

We analyzed 28 RCTs meeting the search criteria. The estimated mean discrepancy index was 0.98 (confidence interval 0.927-1.032 (n = 32)). Subgroup analysis showed that the confidence intervals in all cases included the value 1, except in the subgroup of studies started in the period 2003-2006.

CONCLUSION

In phase III oncology trials, we found no significant differences between the hazard ratios estimated by local investigators and those estimated by blinded independent central reviews. A relatively higher variability, in terms of large CI, was found in trials with biological agents.

Novel Therapies in Chronic Lymphocytic Leukemia: A Rapidly Changing Landscape

OPINION STATEMENT

Treatment landscape of chronic lymphocytic leukemia (CLL) has changed since 2014 after the introduction of inhibitors of B-cell receptor signaling pathway (ibrutinib, acalabrutinib, idelalisib and duvelisib) and the inhibitor of the anti-apoptotic protein BCL-2 (venetoclax). In 2019, novel agents were upgraded from being a "great treatment option" to the "preferred choice" for all lines of treatment after number of randomized clinical trials proved their superiority compared to conventional chemoimmunotherapy (CIT) regimens. A growing number of next-generation molecules are in clinical trials with a promise of improved efficacy and less toxicity. This includes agents with expected better safety profile (zanubrutinib, umbralisib, etc.) or more importantly with a potential to overcome the resistance mechanism to early generation agents (ARQ-531, LOXO-305, or vecabrutinib). Early intervention has once again become an active topic of research and, if proven to provide an overall survival benefit, will eliminate the "watch and wait" strategy for asymptomatic CLL patients. Until then, treatment should only be offered to patients who meet the standard treatment indication in standard practice. With our upgraded therapeutic toolbox, there are and will be many unanswered questions. CLL field will need to define the optimal treatment sequence and most effective combinations with a goal of having a time-limited and chemotherapy-free regimen that provides longest remissions and potentially cure. Cellular immunotherapy with chimeric antigen receptor T-cell (CAR-T) may become available for high-risk CLL along with allogeneic stem cell transplant (allo-SCT). Financial toxicity of novel agents especially when used in combination will need to be an important aspect of research in coming years to avoid unnecessary overtreatment of patients. As current prognostic models (CLL-IPI, etc.) were developed and validated in the CIT era, there is ongoing effort to develop new models using clinical and molecular characteristics to accurately define high-risk CLL in the era of novel agents. We all need to keep in mind that access to the novel agents is currently limited to certain developed countries and every effort should be made to make sure patients around the world also benefit from these outstanding drugs.

Patient Experience Captured by Quality-of-Life Measurement in Oncology Clinical Trials

IMPORTANCE

Quality of life (QoL) is an important consideration in cancer medicine, especially because drugs are becoming more costly and may only result in modest gains in overall survival. However, there has been no descriptive analysis for the points at which QoL is measured in cancer trials.

OBJECTIVE

To estimate the prevalence of studies that measure QoL at different points and see how many studies measure QoL for the entirety of a patient's life.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional analysis includes all articles on oncology clinical trials in the 3 highest-impact oncology journals, published between July 2015 and June 2018, that reported QoL outcomes.

MAIN OUTCOMES AND MEASURES

Data were abstracted on when QoL was assessed and the characteristics of these studies.

RESULTS

For all 149 studies that met inclusion criteria, QoL assessment was high during treatment (104 articles [69.8%]), during follow-up (81 articles [54.4%]), and after the end of the intervention (68 articles [45.6%]). In 5 of the 149 studies (3.4%), QoL was assessed until death, including in only 1 of the 74 studies on metastatic or incurable cancers. Among these 5 studies, only 1 (20%) used a drug intervention, 1 (20%) used a behavioral intervention, and 2 (40%) used a radiation intervention; only 1 of 5 was in the metastatic setting. The number of studies that reported a positive QoL outcome (ie, QoL outcome was more favorable in the intervention group than in the control group) was between 42 of 81 articles (51.9%) and 16 of 28 articles (57.1%) for most QoL assessment points but only 1 of 5 articles (20%) for studies measuring QoL until death.

CONCLUSIONS AND RELEVANCE

This study found that most clinical trials assessed QoL during the treatment or intervention and often during a given amount of follow-up but infrequently assessed QoL on disease progression and rarely followed QoL until the end of the patient's life. Most studies reporting QoL until the end of life reported worse QoL outcomes for the intervention group than the control group. Future research and policy recommendations should consider not just short-term QoL outcomes but QoL outcomes throughout the patient's cancer care.

Five-year survival follow-up of a phase III randomised trial comparing ofatumumab versus physicians' choice for bulky fludarabine-refractory chronic lymphocytic leukaemia: a short report

In 2014, an interim analysis of a phase 3 study was performed to evaluate the effectiveness of ofatumumab in patients with bulky fludarabine-refractory chronic lymphocytic leukaemia (BFR CLL) as compared to physician's choice. The five-year follow-up of this phase 3 trial showed that ofatumumab therapy resulted in a numerically but not significantly longer overall survival. As only few patients had the chance to receive a kinase inhibitor later, the study displays the survival of BFR CLL patients in the period prior to receiving small-molecule inhibitors. Ofatumumab is a well-tolerable treatment option in multiresistant advanced CLL.

A network meta-analysis of maintenance therapy in chronic lymphocytic leukemia

Background

Chronic lymphocytic leukemia (CLL) is incurable through conventional chemoimmunotherapy regimens. Despite durable responses to front-line therapy and sustained remission rates in patients with CLL, a majority of patients eventually relapse in 5 years of initial treatment. The depth of the response may affect the length of response. Maintenance therapies were aimed to deep remissions and extend the period of disease quiescence. Lenalidomide, rituximab and ofatumumab had demonstrated some efficacy as a maintenance therapy compared to no intervention for CLL patients. The relative effect on disease control and safety between different maintenance therapies were unclear.

Methods

We performed a systematic literature review and network meta-analysis to evaluate relative effect on disease control and safety of current available maintenance therapies. We searched PubMed, Embase and Cochrane database up to March 6, 2019. Relevant reference of review article and conference abstract including European Hematology Association Annual Meeting (EHA 2018), American Society of Hematology Annual Meeting (ASH 2018) and American Society of Clinical Oncology Annual Meeting (ASCO 2018) were searched. Randomized controlled trials (RCT) involving current available maintenance therapy including “Lenalidomide”, “Rituximab”, “Ofatumumab”, “Ibrutinib”, “Idelalisib”, “Venetoclax”and “Obinutuzumab”were eligible. Outcomes of interest included progression-free survival (PFS), overall survival (OS) and serious adverse events (SAE) in CLL patients received subsequent maintenance therapy. Two authors CHL and CL) independently assessed eligibility for all identified citations and extracted data from the original trial reports. The selected studies’ risk of bias was assessed following the guidelines of Cochrane Collaboration Handbook.

Results

In total, six phase III RCTs with total 1,615 CLL patients were identified. Maintenance therapy using lenalidomide, rituximab, and ofatumumab demonstrated a statistically significant effect in prolongation of progression-free survival (HR:0.37, 95% CI: 0.27–0.50 of lenalidomide; HR:0.50, 95% CI: 0.38–0.66 of rituximab; HR:0.52, 95% CI:0.41–0.66 of ofatumumab, separately) compared with no intervention; however, for overall survival, the effect of maintenance therapy showed no significant difference versus no intervention (HR: 0.89, 95% CI: 0.70–1.14). Lenalidomide showed the best efficacy for PFS (HR: 0.37, 95% CI: 0.27–0.50, Probability of being best treatment: 96%).

Conclusions

Our network meta-analysis provided an integrated overview of relative efficacy and safety of different maintenance therapies in CLL. All maintenance therapies were effective in reducing the risk of disease progression versus no intervention. Based on current best evidence, maintenance therapy with lenalidomide is the most efficacious option.

Fungal infections following treatment with monoclonal antibodies and other immunomodulatory therapies

Tumor necrosis factor (TNF) is a proinflammatory cytokine involved in a wide range of important physiologic processes and has a pathologic role in some diseases. TNF antagonists (infliximab, adalimumab, etanercept) are effective in treating inflammatory conditions. Antilymphocyte biological agents (rituximab, alemtuzumab), integrin antagonists (natalizumab, etrolizumab and vedolizumab), interleukin (IL)-17A blockers (secukinumab, ixekizumab) and IL-2 antagonists (daclizumab, basiliximab) are widely used after transplantation and for gastroenterological, rheumatological, dermatological, neurological and hematological disorders. Given the putative role of these host defense elements against bacterial, viral and fungal agents, the risk of infection during a treatment with these antagonists is a concern. Fungal infections, both opportunistic and endemic, have been associated with these biological therapies, but the causative relationship is unclear, especially among patients with poor control of their underlying disease or who are undergoing steroid therapy. Potential recipients of these drugs should be screened for latent endemic fungal infections. Cotrimoxazole prophylaxis could be useful for preventing Pneumocystis jirovecii infection in patients over 65 years of age who are taking TNF antagonists, antilymphocyte biological agents or who have lymphopenia and are undergoing concomitant steroid therapy. As with other immunosuppressant drugs, TNF antagonists and antilymphocyte antibodies should be discontinued for patients with active infectious disease.

Targeting CD20: teaching an old dog new tricks

Rituximab was the first monoclonal antibody used for the treatment of a malignancy. In the 22 years since initial approval, it has become a vital component of therapy for a multitude of B-cell malignancies. Within the last several years, however, there has been a robust development of novel agents targeting CD20, including second generation anti-CD20 antibodies, biosimilar antibodies, and subcutaneous formulations that have been approved. The era of passive immunotherapy is now yielding to therapeutic approaches that actively engage the immune system. Emerging approaches leverage immunomodulatory drugs or novel checkpoint inhibitors to enhance CD20 therapy. Recent data sets on bispecific CD3/CD20 antibodies demonstrate exciting early findings, and CD20-directed chimeric antigen receptor T-cell therapies are now entering clinical trials. Anti-CD20 therapies are a vital component of the treatment of B-cell malignancies, and there is a dynamic therapeutic environment with multiple new data sets reviewed here.

Ofatumumab maintenance prolongs progression-free survival in relapsed chronic lymphocytic leukemia: final analysis of the PROLONG study

We report the final analysis of the PROLONG study on ofatumumab maintenance in relapsed chronic lymphocytic leukemia (CLL). In all, 480 patients with CLL in complete or partial remission after second- or third-line treatment were randomized 1:1 to ofatumumab (300 mg first week, followed by 1000 mg every 8 weeks for up to 2 years) or observation. Median follow-up duration was 40.9 months. Median progression-free survival was 34.2 and 16.9 months for ofatumumab and observation arms, respectively, (hazard ratio, 0.55 [95% confidence interval, 0.43–0.70]; P < 0.0001). Median time to next treatment for ofatumumab and observation arms, respectively, was 37.4 and 27.6 months (0.72 [0.57–0.91]; P = 0.0044). Overall survival was similar in both arms; median was not reached (0.99 [0.72–1.37]). Grade ≥ 3 adverse events occurred in 62% and 51% of patients in ofatumumab and observation arms, respectively, the most common being neutropenia (23% and 10%), pneumonia (13% and 12%) and febrile neutropenia (6% and 4%). Up to 60 days after the last treatment, four deaths were reported in the ofatumumab arm versus six in the observation arm, none considered related to ofatumumab. Ofatumumab maintenance significantly prolonged progression-free survival in patients with relapsed CLL and was well tolerated.

Biological Therapy of Hematologic Malignancies: Toward a Chemotherapy- free Era

Less than 70 years ago, the vast majority of hematologic malignancies were untreatable diseases with fatal prognoses. The development of modern chemotherapy agents, which had begun after the Second World War, was markedly accelerated by the discovery of the structure of DNA and its role in cancer biology and tumor cell division. The path travelled from the first temporary remissions observed in children with acute lymphoblastic leukemia treated with single-agent antimetabolites until the first cures achieved by multi-agent chemotherapy regimens was incredibly short. Despite great successes, however, conventional genotoxic cytostatics suffered from an inherently narrow therapeutic index and extensive toxicity, which in many instances limited their clinical utilization. In the last decade of the 20th century, increasing knowledge on the biology of certain malignancies resulted in the conception and development of first molecularly targeted agents designed to inhibit specific druggable molecules involved in the survival of cancer cells. Advances in technology and genetic engineering enabled the production of structurally complex anticancer macromolecules called biologicals, including therapeutic monoclonal antibodies, antibody-drug conjugates and antibody fragments. The development of drug delivery systems (DDSs), in which conventional drugs were attached to various types of carriers including nanoparticles, liposomes or biodegradable polymers, represented an alternative approach to the development of new anticancer agents. Despite the fact that the antitumor activity of drugs attached to DDSs was not fundamentally different, the improved pharmacokinetic profiles, decreased toxic side effects and significantly increased therapeutic indexes resulted in their enhanced antitumor efficacy compared to conventional (unbound) drugs. Approval of the first immune checkpoint inhibitor for the treatment of cancer in 2011 initiated the era of cancer immunotherapy. Checkpoint inhibitors, bispecific T-cell engagers, adoptive T-cell approaches and cancer vaccines have joined the platform so far, represented mainly by recombinant cytokines, therapeutic monoclonal antibodies and immunomodulatory agents. In specific clinical indications, conventional drugs have already been supplanted by multi-agent, chemotherapy-free regimens comprising diverse immunotherapy and/or targeted agents. The very distinct mechanisms of the anticancer activity of new immunotherapy approaches not only call for novel response criteria, but might also change fundamental treatment paradigms of certain types of hematologic malignancies in the near future.

Management of giant cell hepatitis associated with chronic lymphocytic leukemia - a case series and review of the literature

Giant cell hepatitis (GCH) is a rare diagnosis in adults that is found in 0.25% of liver biopsies. GCH has been associated with multiple causes including drugs (6-mercaptopurine, methotrexate), toxins, viruses and autoimmune. GCH has been described in few patients with chronic lymphocytic leukemia (CLL). Here we describe three patients diagnosed with GCH thought to be related to underlying CLL and its management. All of our patients were treated with a combination of immunosuppression as well as CLL-directed therapy to address CLL and concomitant liver disease. GCH is a rare manifestation of active CLL and should be ruled out with prompt liver biopsy in patients with CLL with persistent transaminitis without another attributable cause. Prompt treatment of GCH with immunosuppression is required to prevent long-term liver toxicity. If transaminitis does not improve with immunosuppression alone, the addition of CLL directed therapy should be considered in patients who carry this diagnosis to prevent long-term liver toxicity.

Ofatumumab for acute treatment and prophylaxis of a patient with multiple relapses of acquired thrombotic thrombocytopenic purpura

Acquired thrombotic thrombocytopenic purpura (TTP) is an autoimmune disorder resulting in potentially life-threating systemic thrombotic microangiopathy due to production of antibodies directed against the von Willebrand factor-cleaving protease ADAMTS13. Typically managed with plasma exchange, glucocorticoids, and the first-generation anti-CD20 monoclonal antibody rituximab, patients with multiple relapses or refractory disease present unique management challenges. We describe a case of a young woman with multiple relapses of TTP despite standard therapy who was treated with ofatumumab, a second-generation anti-CD20 monoclonal antibody, after developing a severe hypersensitivity reaction to rituximab precluding its use. Ofatumumab was effective for the treatment of an acute relapse of TTP in combination with plasmapheresis and as a single-agent for prophylaxis. The patient has had no evidence of relapse 2 years after completion of acute treatment and 1 year after completing prophylactic therapy. Hypersensitivity to ofatumumab did not develop.

Anti-CD20 monoclonal antibodies: reviewing a revolution

Since the inception of rituximab in the 1990s, anti-CD20 monoclonal antibodies have revolutionised the treatment of B cell hematological malignancies and have become a cornerstone of modern gold-standard practice. Additionally, the potent efficacy of these agents in depleting the B cell compartment has been used in the management of a broad array of autoimmune diseases. Multiple iterations of these agents have been investigated and are routinely used in clinical practice. In this review, we will discuss the physiology of CD20 and its attractiveness as a therapeutic target, as well as the pharmacology, pre-clinical and clinical data for the major anti-CD20 monoclonal antibodies: rituximab, obinutuzumab and ofatumumab.

Remission maintenance treatment options in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) treatment has come a long way in the last two decades, producing increases in tumor control to the point of generating sizeable numbers of patients with undetectable minimal residual disease and creating overall survival benefits in randomized comparisons. Most of this has been achieved by limited-term treatment approaches including chemotherapeutic and immune-therapeutic drugs. More recently, novel therapies targeting signaling pathways essential for the survival of the neoplastic clones have opened avenues that provide disease control in long-term treatment designs, mostly without producing deep remissions. In this disease, where current treatments are largely unable to effect a cure, prolonged therapy designs using maintenance approaches are explored and 5 randomized studies of maintenance have recently been published. This review shall summarize available results from a systematic literature review in a clinical context and outline basic biology principles that should be heeded in this regard.

A phase 2 study of ofatumumab (Arzerra®) in combination with a pan-AKT inhibitor (afuresertib) in previously treated patients with chronic lymphocytic leukemia (CLL)

AKT plays a centralized role in tumor proliferation and survival and is aberrantly activated in chronic lymphocytic leukemia (CLL). In this phase 2 trial, 30 relapsed/refractory CLL patients were treated with combination afuresertib, a novel oral AKT inhibitor, and ofatumumab for 6 months, followed by afuresertib maintenance for 12 months. We aimed to achieve deeper and more durable responses, without requiring long-term continuous treatment. Treatment was generally well tolerated but respiratory infections were common, with 18% severe requiring hospitalization. Hematologic toxicities were manageable (grade 3-4 neutropenia 39%). At a median follow-up of 13.4 months, overall responses were 50% (complete responses 3.6%). Median progression-free survival was 8.5 months and overall survival 34.8 months. Combination therapy with ofatumumab and afuresertib is active and well tolerated, but does not appear to lead to durable responses and may not provide additional benefit over single-agent ofatumumab in relapsed/refractory CLL. Novel agent combinations are currently undergoing intense investigation.

Chronic Lymphocytic Leukemia: Diagnosis and Treatment

The complexity of the treatment of patients with chronic lymphocytic leukemia has increased substantially over the past several years as a consequence of the advent of novel biological agents such as ibrutinib, idelalisib, and venetoclax, as well as increasingly potent anti-CD20 monoclonal antibodies. In addition, the identification of molecular predictive markers and the introduction of more sensitive and sophisticated techniques to assess minimal residual disease have allowed optimization of the use of chemoimmunotherapy and targeted therapies and may become standard of care in the future. This review summarizes the diagnosis, prognostication, and treatment of patients with chronic lymphocytic leukemia with emphasis on new prognostic and predictive factors and novel treatment strategies.

Review of targeted therapy in chronic lymphocytic leukemia: what a radiologist needs to know about CT interpretation

The last 5 years have been marked by profound innovation in the targeted treatment of chronic lymphocytic leukemia (CLL) and indolent lymphomas. Using CLL as a case study, we present a timeline and overview of the current treatment landscape for the radiologist, including an overview of clinical and radiological features of CLL, discussion of the targeted agents themselves, and the role of imaging in response and toxicity assessment. The goal is to familiarize the radiologist with multiple Food and Drug Administration (FDA)-approved targeted agents used in this setting and associated adverse events which are commonly observed in this patient population.

Chronic lymphocytic leukaemia

Important advances in understanding the pathogenesis of chronic lymphocytic leukaemia in the past two decades have led to the development of new prognostic tools and novel targeted therapies that have improved clinical outcome. Chronic lymphocytic leukaemia is the most common type of leukaemia in developed countries, and the median age at diagnosis is 72 years. The criteria for initiating treatment rely on the Rai and Binet staging systems and on the presence of disease-related symptoms. For many patients with chronic lymphocytic leukaemia, treatment with chemotherapy and anti-CD20 monoclonal antibodies is the standard of care. The impressive efficacy of kinase inhibitors ibrutinib and idelalisib and the BCL-2 antagonist venetoclax have changed the standard of care in specific subsets of patients. In this Seminar, we review the recent progress in the management of chronic lymphocytic leukaemia and highlight new questions surrounding the optimal disease management.

Rituximab, cladribine, and cyclophosphamide (RCC) induction with rituximab maintenance in chronic lymphocytic leukemia: PALG - CLL4 (ML21283) trial

OBJECTIVES

PALG CLL4 is the first, randomized, phase IIIb study with rituximab, cladribine, and cyclophosphamide (RCC) induction and subsequent maintenance with rituximab in previously untreated chronic lymphocytic leukemia (CLL) patients.

METHODS

The induction treatment consisted of 6 RCC cycles regimen. Patients with complete response (CR) or partial response (PR) after an induction phase were randomized into a maintenance arm with rituximab or an observational arm.

RESULTS

In the intention-to-treat population, 97 patients completed the induction phase with an overall response rate (ORR) of 73.2% (CR 22.7%, PR 50.5%). Subsequently, 66 patients were randomized into the rituximab maintenance arm (n = 33) or the observational arm (n = 33). CR rates were 57.1% in the maintenance group vs 50% in the observational group. PFS was significantly longer in the rituximab maintenance vs the observational arm (P = .028). The multivariate Cox model indicated that del17p (P = .006) and elevated beta-2-microglobulin (P = .015) significantly increased the hazard ratio (HR) of progression, whereas the presence of CD38 (P = .013) significantly decreased it; maintenance therapy with rituximab (P < .0001) significantly decreased the HR of disease progression.

CONCLUSIONS

The study confirmed the high efficacy and acceptable safety profile of induction therapy with RCC and maintenance therapy with rituximab in previously untreated patients with CLL.