Rituximab versus a watch-and-wait approach in patients with advanced-stage, asymptomatic, non-bulky follicular lymphoma: an open-label randomised phase 3 trial

What do we know about duodenal-type follicular lymphoma? From pathological definition to treatment options

Duodenal-type follicular lymphoma (DFL) is a newly recognised variant of follicular lymphoma (FL), although little is known about its biology and clinical evolution. In general, patients tend to have mild symptoms and do not require therapy, comparable with other forms of low-tumour burden asymptomatic FL. Specific pathological features, such as a dendritic cell meshwork, low expression of CD10 and upregulation of activation-induced cytidine deaminase can help the diagnosis. The molecular landscape of DFL is similar to the classical nodal presentation of FL, although studies using gene expression profiling demonstrate a close relation with MALT lymphomas. Markers associated with inflammation have suggested that the microenvironment plays a likely role in the pathogenesis of DFL and its low progression rate. Clinical series published vary between 20-63 patients with an estimated overall survival between 92-100% and a median follow-up ranging between 20 and 107 months. Treatment options include a watch and wait strategy, rituximab monotherapy and radiotherapy. In this review, we summarise current pathological data and treatment studies in DFL.

Follicular lymphoma

Follicular lymphoma (FL) is a systemic neoplasm of the lymphoid tissue displaying germinal centre (GC) B cell differentiation. FL represents ~5% of all haematological neoplasms and ~20-25% of all new non-Hodgkin lymphoma diagnoses in western countries. Tumorigenesis starts in precursor B cells and becomes full-blown tumour when the cells reach the GC maturation step. FL is preceded by an asymptomatic preclinical phase in which premalignant B cells carrying a t(14;18) chromosomal translocation accumulate additional genetic alterations, although not all of these cells progress to the tumour phase. FL is an indolent lymphoma with largely favourable outcomes, although a fraction of patients is at risk of disease progression and adverse outcomes. Outcomes for FL in the rituximab era are encouraging, with ~80% of patients having an overall survival of >10 years. Patients with relapsed FL have a wide range of treatment options, including several chemoimmunotherapy regimens, phosphoinositide 3-kinase inhibitors, and lenalidomide plus rituximab. Promising new treatment approaches include epigenetic therapeutics and immune approaches such as chimeric antigen receptor T cell therapy. The identification of patients at high risk who require alternative therapies to the current standard of care is a growing need that will help direct clinical trial research. This Primer discusses the epidemiology of FL, its molecular and cellular pathogenesis and its diagnosis, classification and treatment.

Histological transformation in malignant lymphoma: a possible role of PET/CT and circulating tumor DNA as noninvasive diagnostic tools

Introduction: Transformation is a multi-step event wherein indolent lymphomas, such as follicular lymphomas, are converted into an aggressive subtype, such as diffuse large B-cell lymphoma. This process progresses not only through mutations in several of the causative genes, such as TP53, CDKN2A/B, or MYC, but also through epigenetic or micro-environmental changes. Excisional biopsy is recommended when transformation is clinically suspected.Areas covered: The authors summarized the current knowledge regarding the clinicopathological and molecular features of transformed lymphomas and discussed the relevance of re-biopsy in the diagnosis of transformation, comparing it with noninvasive diagnostic tools [fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) and circulating tumor DNA (ctDNA) analysis].Expert opinion: Pathological confirmation by biopsy is considered the golden standard for diagnosis and is indispensable for determining subsequent treatment strategies. The potential weakness of this approach is its invasiveness and the unavailability of pathological findings outside the biopsied areas. In the context of relapse, PET/CT is used mainly for the selection of the best suitable biopsy site, while ctDNA has the potential for detecting systemic genomic changes associated with relapse before clinical presentation. Future investigations should be focused on combining biopsies with new technologies for an early and accurate diagnosis of transformation.

Follicular Lymphoma: Recent and Emerging Therapies, Treatment Strategies, and Remaining Unmet Needs

Follicular lymphoma (FL) is a heterogeneous disease with varying prognosis owing to differences in clinical, laboratory, and disease parameters. Although generally considered incurable, prognosis for early- and advanced-stage disease has improved because of therapeutic advances, several of which have resulted from elucidation of the biologic and molecular basis of the disease. The choice of treatment for FL is highly dependent on patient and disease characteristics. Several tools are available for risk stratification, although limitations in their routine clinical use exist. For limited disease, treatment options include radiotherapy, rituximab monotherapy or combination regimens, and surveillance. Treatment of advanced disease is often determined by tumor burden, with surveillance or rituximab considered for low tumor burden and chemoimmunotherapy for high tumor burden disease. Treatment for relapsed or refractory disease is influenced by initial first-line therapy and the duration and quality of the response. Presently, there is no consensus for treatment of patients with early or multiply relapsed disease; however, numerous agents, combination regimens, and transplant options have demonstrated efficacy. Although the number of therapies available to treat FL has increased together with an improved understanding of the underlying biologic basis of disease, the best approach to select the most appropriate treatment strategy for an individual patient at a particular time continues to be elucidated. This review considers prognostication and the evolving treatment landscape of FL, including recent and emergent therapies as well as remaining unmet needs. IMPLICATIONS FOR PRACTICE: In follicular lymphoma, a personalized approach to management based on disease biology, patient characteristics, and other factors continues to emerge. However, application of current management requires an understanding of the available therapeutic options for first-line treatment and knowledge of current development in therapies for previously untreated and for relapsed or refractory disease. Thus, this work reviews for clinicians the contemporary data in follicular lymphoma, from advances in characterizing disease biology to current treatments and emerging novel therapies.

Yttrium-90 ibritumomab tiuxetan consolidation versus rituximab maintenance therapy after induction chemotherapy in patients with indolent non-Hodgkin lymphoma: a single-institution experience

OBJECTIVES

Indolent B-cell non-Hodgkin lymphomas (iNHLs) are considered incurable. Rituximab maintenance and yttrium-90 ibritumomab tiuxetan (⁹⁰Y-IT) consolidation are promising post-remission therapies. However, only one randomized phase II trial has compared their efficacies and adverse effects. Here, we compared the efficacy and safety of ⁹⁰Y-IT consolidation and rituximab maintenance in iNHL patients.

METHODS

We retrospectively examined 75 iNHL patients with complete or partial response after initial chemotherapy between January 2008 and December 2018. Twenty-seven patients received ⁹⁰Y-IT consolidation and 48 received rituximab maintenance (every 2 months for 2 years). Progression-free survival (PFS), overall survival (OS), and time to next treatment (TTNT) were estimated from the start of the treatment, and adverse effects were evaluated.

RESULTS

After a median 3.6-year follow-up, the 5-year PFSs of the ⁹⁰Y-IT consolidation and rituximab maintenance groups were 75.5% and 82.4%, respectively (log-rank test, p = 0.839), and the 5-year OSs were 100% and 97.8%, respectively (log-rank test, p = 0.465). The corresponding median TTNTs were not reached (log-rank test, p = 0.804). The commonest adverse effect with ⁹⁰Y-IT consolidation was hematotoxicity; lower rates and grades of cytopenia were observed in patients who received rituximab maintenance. Secondary malignancies were observed in 1 patient (4%) who received ⁹⁰Y-IT consolidation and 2 patients (4.2%) who received rituximab maintenance (Fisher's exact test, p > 0.99).

CONCLUSION

⁹⁰Y-IT consolidation and rituximab maintenance were similar with respect to PFS, OS, and TTNT. However, the features and grades of adverse effects significantly differed. Patient-specific characteristics should be considered when deciding post-remission treatments.

[Follicular lymphoma: An update]

Follicular lymphoma, the second most common lymphoma, is characterized by its slow growth and is often considered incurable in advanced stages. Progresses in biology have contributed to better understand the complex and successive mechanisms of development of this pathology, whose diagnosis is based on a lymph node biopsy. However, the prognosis of the patients is heterogeneous and several indexes have been proposed to identify groups of patients with a similar life expectancy, in order to guide the therapeutic choices. The treatment has been modified in the last 20 years by the emergence of anti-CD20 monoclonal antibodies which constitute, alone or in combination, of the cornerstone of therapeutic management. After staging using, in particular, 18-fluorodeoxyglucose positron emission tomography, the therapeutic strategy will be adapted for each patient, ranging from simple watchful waiting to a combination of chemotherapy and anti-CD20 antibodies. Relapses (which often require a new lymph node biopsy to eliminate a possible histological transformation into an aggressive lymphoma with poorer prognosis) remain common but are still accessible to effective therapeutic interventions. Thanks to these advances, the median life expectancy of patients with follicular lymphoma now exceeds 15 years.

M7-FLIPI is not prognostic in follicular lymphoma patients with first-line rituximab chemo-free therapy

The clinical course of follicular lymphoma (FL) is highly variable. Recently the m7-FL international prognostic index (FLIPI) integrating performance status, FLIPI score and the mutational status of seven genes, was shown to stratify patients into "low-risk" and "high-risk" with respect to 5-year failure-free survival after first-line immunochemotherapy. Our aim was to evaluate the model after rituximab without chemotherapy. The Nordic Lymphoma Group performed two randomized clinical trials on indolent lymphoma patients receiving single rituximab and rituximab with interferon-α2a. In total, 95 FL patients had sufficient fresh-frozen diagnostic material for sequencing. A targeted panel for the genes EZH2, ARID1A, MEF2B, EP300, FOXO1, CREBBP and CARD11 was utilized for m7-FLIPI score calculation. With a median follow-up of 10·6 years, 76% of patients were alive. No difference in time to treatment failure (TTF), defined as the interval between start of trial therapy and initiation of new therapy or death, nor overall survival (OS) was found between the m7-FLIPI risk groups (log-rank P = 0·94 and 0·99, respectively). EZH2 mutations were associated with longer TTF (log-rank P = 0·04) and in EP300 mutations were associated with shorter TTF (log-rank P = 0·01). We conclude that the prognostic value of the m7-FLIPI clinicogenetic model seems dependent on therapeutic regimen.

Diagnosis and management of follicular lymphoma: A comprehensive review

Follicular Lymphoma (FL) is an indolent lymphoma and may have various clinical courses. Worldwide, FL is the second most common non-Hodgkin lymphoma (NHL) type after diffuse large B-cell lymphoma. In this review article, the author is discussing relevant diagnostic tools, prognostic factors, and updated study results on the management of patients with newly diagnosed and relapsed/refractory FL. Controversies in the treatment, maintenance therapy, stem cell transplantation, and novel treatment approaches will be comprehensively discussed.

How I manage patients with follicular lymphoma

Recent advances in the treatment of follicular lymphoma (FL) have provided insight into molecular and biological influences on pathogenesis and prognosis. Additionally, numerous available treatment strategies for both newly diagnosed and relapsed disease require thoughtful consideration of patient selection to avoid the burden of overtreatment and toxicities. This review provides a broad overview on our approach to managing patients with low grade FL.

Real world data as a key element in precision medicine for lymphoid malignancies: potentials and pitfalls

Molecular genetic studies of lymphoma have led to refinements in disease classification in the most recent World Health Organization update. Nevertheless, a 'one-size-fits-most' treatment strategy based on morphology remains widely used for lymphoma despite significant molecular heterogeneity within histopathologically-defined subtypes. Precision medicine aims to improve patient outcomes by leveraging disease- and patient-specific information to optimise treatment strategies, but implementation of precision medicine strategies is challenged by the biological diversity and rarity of lymphomas. In this review, we explore existing and emerging real-world data sources that can be used to facilitate the development of precision medicine strategies in lymphoma. We provide illustrative examples of the use of real-world analyses to refine treatment strategies, provide comparators for clinical trials, improve risk-stratification to identify patients with unmet clinical needs and describe long-term and rare toxicities.

Transformation of follicular lymphoma to double-hit lymphoma during adjuvant chemotherapy for concurrent ovarian carcinoma

The frequency of multiple primary malignant neoplasms (MPMN) is increasing due to population aging. Since consensus guidelines for the treatment of MPMN are lacking, treatment strategies are determined by disease status on a per-patient basis. In this report, we describe a case of MPMN with follicular lymphoma (FL) grade 1 that transformed to double-hit lymphoma during adjuvant chemotherapy for concurrent ovarian carcinoma. A 64-year-old woman was diagnosed with MPMN of FL and endometrioid carcinoma by staging laparotomy and lymph node biopsy. She received four cycles of adjuvant chemotherapy (carboplatin and paclitaxel) for endometrioid carcinoma, but during chemotherapy, the FL grade 1 transformed to double-hit lymphoma. We speculate that adjuvant chemotherapy for endometrioid carcinoma may have triggered the transformation of FL in the present case.

Short regimen of rituximab plus lenalidomide in follicular lymphoma patients in need of first-line therapy

The SAKK 35/10 phase 2 trial, developed by the Swiss Group for Clinical Cancer Research and the Nordic Lymphoma Group, compared the activity of rituximab vs rituximab plus lenalidomide in untreated follicular lymphoma patients in need of systemic therapy. Patients were randomized to rituximab (375 mg/m² IV on day 1 of weeks 1-4 and repeated during weeks 12-15 in responding patients) or rituximab (same schedule) in combination with lenalidomide (15 mg orally daily for 18 weeks). Primary end point was complete response (CR)/unconfirmed CR (CRu) rate at 6 months. In total, 77 patients were allocated to rituximab monotherapy and 77 to the combination (47% poor-risk Follicular Lymphoma International Prognostic Index score in each arm). A significantly higher CR/CRu rate at 6 months was documented in the combination arm by the investigators (36%; 95% confidence interval [CI], 26%-48% vs 25%; 95% CI, 16%-36%) and confirmed by an independent response review of computed tomography scans only (61%; 95% CI, 49%-72% vs 36%; 95% CI, 26%-48%). After a median follow-up of 4 years, significantly higher 30-month CR/CRu rates and longer progression-free survival (PFS) and time to next treatment (TTNT) were observed for the combination. Overall survival (OS) rates were similar in both arms (≥90%). Toxicity grade ≥3 was more common in the combination arm (56% vs 22% of patients), mainly represented by neutropenia (23% vs 7%). Addition of lenalidomide to rituximab significantly improved CR/CRu rates, PFS, and TTNT, with expected higher, but manageable toxicity. The excellent OS in both arms suggests that chemotherapy-free strategies should be further explored. This trial was registered at www.clinicaltrials.gov as #NCT01307605.

Current approaches and future perspectives for advanced-stage follicular lymphoma with a low tumor burden

The introduction of a chimeric anti-CD20 monoclonal antibody, rituximab, for the treatment of follicular lymphoma (FL) has dramatically improved the prognosis of this disease. Despite advances in therapy, the disease remains incurable with current standard therapeutic strategies. For advanced-stage and high-tumor-burden FL patients, a combination of rituximab with chemotherapy has improved the overall survival rates, and subsequent rituximab maintenance following successful rituximab-based chemotherapy induction also prolongs progression-free survival. Conversely, for advanced-stage low-tumor-burden FL patients, watchful waiting remains the appropriate approach, whereas rituximab monotherapy has also been suggested as a good alternative. However, the optimal timing of rituximab monotherapy in low-tumor-burden FL patients has not been clarified. It is important to address this issue for chemo-free treatment strategies. Furthermore, a predictive model for advanced low-tumor-burden patients is required to appropriately identify those patients who may benefit from immediate treatment. In this review, we address the current treatment approaches and present potential future management strategies for advanced-stage, low-tumor-burden patients.

Spontaneous Regression of Clinically Indolent Lymphomas Revealed by 18F-FDG PET/CT

A 48-year-old man and a 55-year-old woman, who were diagnosed with follicular lymphoma and small B lymphocytic cell lymphoma, respectively, underwent initial "watch-and-wait" approach against lymphoma. The initial F-FDG PET/CT of both patients showed multiple FDG-avid lymph nodes in the neck, mediastinum, abdomen, and inguinal regions. During their active surveillance, the follow-up PET/CT of both patients revealed spontaneous regression of lymphoma.

Transformed follicular lymphoma in the rituximab era: A report from the Spanish Lymphoma Oncology Group

Follicular lymphoma (FL) is the second most common non-Hodgkin lymphoma (NHL) subtype. The histological transformation (HT) of FL is an event considered frequent in the natural history of this tumor. We studied the transformation rates, predictive factors, and treatment characteristics that may impact in the survival of patients with FL and HT. A total of 1074 patients diagnosed with FL were prospectively enrolled from 1990 to 2016 in a Spanish registry. Sixty-four HTs were recorded based on clinical criteria (55%) or histological confirmation (45%). The cumulative incidence rate of transformation at 5 years is 7.3%. The 5-year overall survival (OS) without HT was 85% (95% confidence interval [CI], 70%-90%) vs 66% (95% CI, 51%-76%; P = 0.0012) with HT. Factors associated with HT were elevated lactate dehydrogenase (LDH) (odds ratio [OR] 1.83), intermediate-high Follicular lymphoma international prognostic index (FLIPI) (OR 2.16-OR 3.21), B symptoms (OR 2.46), or Eastern Cooperative Oncology Group (ECOG) 1 (OR 2.35). Treatment options related to HT were "watch and wait" or no rituximab or anthracyclines initially. A 5-year OS for patients treated with chemotherapy before HT was 55% (95% CI, 38%-69%) versus 81% (95% CI, 53%-93%; P = 0.009) for those who had not received it. The HT rate has decreased after the introduction of rituximab, as has been previously described. The timing of this treatment had an impact on the survival of these patients.

AUGMENT: A Phase III Study of Lenalidomide Plus Rituximab Versus Placebo Plus Rituximab in Relapsed or Refractory Indolent Lymphoma

PURPOSE

Patients with indolent non-Hodgkin lymphoma typically respond well to first-line immunochemotherapy. At relapse, single-agent rituximab is commonly administered. Data suggest the immunomodulatory agent lenalidomide could increase the activity of rituximab.

METHODS

A phase III, multicenter, randomized trial of lenalidomide plus rituximab versus placebo plus rituximab was conducted in patients with relapsed and/or refractory follicular or marginal zone lymphoma. Patients received lenalidomide or placebo for 12 cycles plus rituximab once per week for 4 weeks in cycle 1 and day 1 of cycles 2 through 5. The primary end point was progression-free survival per independent radiology review.

RESULTS

A total of 358 patients were randomly assigned to lenalidomide plus rituximab (n = 178) or placebo plus rituximab (n = 180). Infections (63% v 49%), neutropenia (58% v 23%), and cutaneous reactions (32% v 12%) were more common with lenalidomide plus rituximab. Grade 3 or 4 neutropenia (50% v 13%) and leukopenia (7% v 2%) were higher with lenalidomide plus rituximab; no other grade 3 or 4 adverse event differed by 5% or more between groups. Progression-free survival was significantly improved for lenalidomide plus rituximab versus placebo plus rituximab, with a hazard ratio of 0.46 (95% CI, 0.34 to 0.62; P < .001) and median duration of 39.4 months (95% CI, 22.9 months to not reached) versus 14.1 months (95% CI, 11.4 to 16.7 months), respectively.

CONCLUSION

Lenalidomide improved efficacy of rituximab in patients with recurrent indolent lymphoma, with an acceptable safety profile.

Recent advances in the first-line treatment of follicular non-Hodgkin lymphoma

Follicular lymphoma (FL) is the most common type of indolent B-cell lymphoma. Twenty years ago, FL was considered an indolent lymphoma with a long survival time but without a high rate of complete remission with chemotherapies. The use of rituximab has improved the response and survival of patients with this lymphoma. More recently, development of biological knowledge and use of targeted drugs have offered new perspectives, including improvement of response rates and survival with chemo-free treatment strategies. In 2019, patients have a 10-year overall survival probability of over 70%. Histological transformation to more aggressive lymphoma and treatment relapses remain a medical challenge, especially for patients relapsing within two years. This article will review the recent advances in the treatment of FL. As the use of new drugs is directly related to the development of biological aspects, we will first summarize recent advances in biological aspects of FL.

Salvage Treatment and Survival for Relapsed Follicular Lymphoma Following Primary Radiation Therapy: A Collaborative Study on Behalf of ILROG

PURPOSE

We previously reported that ∼30% of patients with localized follicular lymphoma (FL) staged by ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography receiving primary radiation therapy (RT) will relapse within 5 years. We sought to report outcomes for those who relapsed.

METHODS AND MATERIALS

We conducted a multicenter, retrospective study of patients aged ≥18 years who received RT ≥ 24 Gy for stage I to II, grade 1 to 3A FL, staged with ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography-computed tomography. Observation was defined as >6 months without treatment from relapse. Overall survival (OS) and freedom from progression (FFP) were estimated with Kaplan-Meier analysis and univariable and multivariable analyses with Cox regression.

RESULTS

Of 512 patients with median follow-up of 52 months, 149 (29.1%) developed recurrent lymphoma at a median of 23 months (range, 1-143) after primary RT. Median follow-up was 33 months after relapse. Three-year OS was 91.4% after recurrence. OS was significantly worse for those with relapse ≤12 months from date of diagnosis versus all others-88.7% versus 97.6%, respectively (P = .01)-and remained significantly worse on multivariable analyses (follicular lymphoma international prognostic index-adjusted hazard ratio, 3.61; P = .009). Histology at relapse included 93 indolent (grade 1-3A), 3 FL grade 3B/not otherwise specified, and 18 diffuse large B-cell lymphoma; 35 patients did not undergo biopsy. Of those with follow-up ≥3 months who underwent biopsy (n = 74) or had presumed (n = 23) indolent recurrence, 58 patients (59.8%) were observed, 19 (19.6%) had systemic therapy, 16 (16.5%) had RT, and 4 (4.1%) had systemic therapy + RT. For patients with indolent recurrences that were observed, 3-year FFP or freedom from treatment was 56.6% (median, 48 months). For all patients with biopsied/presumed indolent recurrence receiving salvage treatment (n = 59, including 20 initially observed) 3-year FFP was 73.9%.

CONCLUSIONS

Prognosis for patients with relapsed FL after primary radiation therapy is excellent, supporting the role of primary radiation in the management of early stage disease. Patients with localized FL treated with primary RT who experience early relapse (<12 months) have inferior survival compared with those with longer disease-free interval.

Distinctive incidence patterns of follicular lymphoma in Taiwan: Implications of ethnic differences

BACKGROUND

Follicular lymphoma (FL) is less prevalent in Asians, but detailed epidemiological analyses were not available. This study aimed to characterize the epidemiologic features of FL in Taiwan to explore the factors relevant to disease development and prognosis.

METHODS

We obtained epidemiological data for Taiwanese citizens during 1990-2012 from Taiwan's National Cancer Registry Database, and the corresponding data for US Caucasians from the Surveillance, Epidemiology, and End Results Program. Changes in incidence rates were evaluated with age-period-cohort (APC) analyses. Patient outcomes were compared with 5-year relative survival rates (RS) estimates.

RESULTS

Incidence rates of FL in Taiwan increased continuously during the study period (0.34 to 0.91 per 100 000 person-year from 1993-1997 to 2008-2012 in men, and from 0.29 [1993-1997] to 0.81 [2008-2012] in women), while rates in the US remained stable in both sexes, ranging between 3.73 and 3.96 in men and between 3.24 and 3.55 in women. Estimates of average annual percentage changes in incidence were significantly positive in Taiwan, but not in US Caucasians. Notably, the APC analysis identified a strong birth-cohort effect in Taiwan, corresponding to environmental alterations present during the study period. The estimated 5-year RS rates in both populations showed steady improvement, but the RS in Taiwanese patients was consistently 10% lower than in US Caucasians.

CONCLUSION

A distinct increasing trend of incidence with a strong birth-cohort effect was identified in Taiwan, providing evidence of the association between environmental factors and disease development.

Active surveillance for nodular lymphocyte-predominant Hodgkin lymphoma

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare subtype of lymphoma that, like other Hodgkin lymphomas, has historically been treated aggressively. However, in most cases, NLPHL has an indolent course, which raises the question of to what extent these patients require aggressive upfront treatment. We describe the management and outcomes of consecutive NLPHL patients diagnosed at Memorial Sloan Kettering Cancer Center (MSK), with a focus on evaluating active surveillance. All patients aged 16 years or older diagnosed and followed at MSK between 1974 and 2016 were included. Treatment outcomes were compared between management with active surveillance and other strategies. We identified 163 consecutive patients who were treated with radiotherapy alone (46%), active surveillance (23%), chemotherapy (16%), combined modality (12%), or rituximab monotherapy (4%). Median follow-up was 69 months. Five-year progression-free survival (PFS), second PFS (PFS2), and overall survival (OS) estimates were 85% (95% confidence interval [CI], 78-90), 97% (95% CI, 92-99), and 99% (95% CI, 95-100), respectively. Only 1 of 7 deaths was lymphoma related. Patients managed with active surveillance had slightly shorter PFS than those receiving any active treatment, with 5-year PFS of 77% (95% CI, 56-89) vs 87% (95% CI, 79-92; P = .017). This difference did not translate into better PFS2 or OS. Only 10 patients managed with active surveillance (27%) eventually required treatment, after a median of 61 months, and none died. NLPHL has an excellent prognosis. Within the limitations of a retrospective analysis, active surveillance is a viable initial management strategy for selected NLPHL patients.

One Size Does Not Fit All: Who Benefits From Maintenance After Frontline Therapy for Follicular Lymphoma?

Follicular lymphoma (FL) is the second most common non-Hodgkin lymphoma and the most common indolent B-cell malignancy. The disease often presents in advanced stage and can often be observed before initiation of therapy. Although the incidence is only approximately 15,000 new cases per year, the prevalence is substantially higher owing to the favorable overall survival (OS) of most patients. The most impactful advance responsible for the improvement of OS in FL was the introduction of the anti-CD20 monoclonal antibody (mAb) rituximab over 20 years ago. Phase III trials demonstrate that rituximab improves the OS in FL when combined with chemotherapy. However, unlike aggressive B-cell lymphomas, advanced stage FL is generally incurable and often displays a pattern of progressively shorter remissions with subsequent lines of therapy. Hence, maintenance strategies have been developed to prolong remissions achieved with frontline therapy. The value of maintenance after frontline therapy has been most extensively studied with extended treatment of anti-CD20 mAb, but recent approaches include chemotherapy-free combinations and targeted therapies given for extended durations. Here, we review relevant data that provide rationale in support of maintenance therapy in FL as well as the risks and limitations of a "one-size-fits-all" approach. Importantly, we note the biologic and clinical heterogeneity across patients with FL that must be considered when making clinical decisions. Finally, we highlight ongoing research that explores response-adapted approaches based on the depth of response as defined by PET scans and assays for minimal residual disease (MRD) that aim to better personalize individual management strategies.

The prognostic significance of PFS24 in follicular lymphoma following firstline immunotherapy: A combined analysis of 3 CALGB trials

Follicular lymphoma (FL) patients treated with firstline R‐CHOP who experience progression of disease (POD) within 2 years have a shorter survival than those who do not have POD within 2 years. Whether this observation holds for patients treated initially with biologic immunotherapy alone is unknown. We performed a retrospective analysis of 174 patients pooled from three frontline rituximab (R)‐based nonchemotherapy doublet trials: R‐galiximab (Anti‐CD80, CALGB 50402), R‐epratuzumab (Anti‐CD22, CALGB 50701), and R‐lenalidomide (CALGB 50803) to determine outcomes of early progressors and risk factors for early POD, defined as progression within 24 months from study entry. Twenty‐eight percent (48/174) of patients had early POD. After adjusting for the Follicular Lymphoma International Prognostic Index (FLIPI), patients with early POD from study entry had a worse OS compared with patients who did not progress within 2 years (HR = 4.33 (95% CI 1.50‐12.5), P = 0.007). For early POD, the 2‐year survival was 80% vs 99% for nonearly POD, and the 5‐year survival was 74% vs 90%, respectively. These findings suggest that the adverse survival of patients with early POD may be independent of initial treatment modality.

Efficacy, pharmacokinetics, and safety of the biosimilar CT-P10 in comparison with rituximab in patients with previously untreated low-tumour-burden follicular lymphoma: a randomised, double-blind, parallel-group, phase 3 trial

BACKGROUND

Studies in patients with rheumatoid arthritis and advanced follicular lymphoma have shown that CT-P10, a rituximab biosimilar, has equivalent or non-inferior efficacy and pharmacokinetics to rituximab. We aimed to assess the therapeutic equivalence of single-agent CT-P10 and rituximab in patients with newly diagnosed low-tumour burden follicular lymphoma.

METHODS

In this ongoing, randomised, double-blind, parallel-group, active-controlled, phase 3 trial, adult patients (≥18 years) with stage II-IV low-tumour-burden follicular lymphoma were randomly assigned (1:1) using an interactive web or voice response system stratified by region, stage, and age to CT-P10 or US-sourced rituximab. Patients received CT-P10 or rituximab (375 mg/m² intravenous) on day 1 of four 7-day cycles (induction period). Patients who had disease control after the induction period continued to a maintenance period of CT-P10 or rituximab administered every 8 weeks for six cycles and, if completed, a second year of maintenance therapy of additional CT-P10 (every 8 weeks for six cycles) was offered. The study was partially unmasked after database lock (Feb 23, 2018) for all data up to 7 months (before cycle 3 of the maintenance period). The primary endpoint was the proportion of patients who achieved an overall response by 7 months in the intention-to-treat population. Efficacy equivalence was shown if the two-sided 90% CIs for the treatment difference in the proportion of responders between CT-P10 and rituximab was within the equivalence margin of 17%. This trial is registered with ClinicalTrials.gov, number NCT02260804.

FINDINGS

Between Nov 9, 2015, and Jan 4, 2018, 402 patients were assessed for eligibility, of whom 258 were randomly assigned: 130 to CT-P10 and 128 to rituximab. 108 (83%) of 130 patients assigned to CT-P10 and 104 (81%) of 128 assigned to rituximab achieved an overall response by month 7 (treatment difference estimate 1·8%; 90% CI -6·43 to 10·20). Therapeutic equivalence was shown (90% CIs were within the prespecified margin of 17%). The most common grade 3 or 4 treatment-emergent adverse events were decreased neutrophil count (two grade 3 in the CT-P10 group) and neutropenia (one in each group); all other grade 3 or 4 treatment-emergent adverse events occurred in one patient each. Six (5%) of 130 patients who received CT-P10 and three (2%) of 128 who received rituximab experienced at least one treatment-emergent serious adverse event.

INTERPRETATION

CT-P10 was equivalent to rituximab in terms of efficacy and was well tolerated. CT-P10 monotherapy is suggested as a new therapeutic option for patients with low-tumour-burden follicular lymphoma.

FUNDING

Celltrion, Inc.

Rituximab With Involved Field Irradiation for Early-stage Nodal Follicular Lymphoma: Results of the MIR Study

The MabThera and Involved field Radiotherapy study investigated efficacy and safety of involved field (IF) radiotherapy in combination with the anti-CD20 antibody Rituximab for early-stage follicular lymphoma (FL) in a prospective, single-arm multicenter phase 2 design. Eighty-five stage I–II FL patients received 8 cycles of Rituximab (375 mg/m²) and IF irradiation (30/40 Gy). The primary endpoint was progression-free survival (PFS) 2 years from treatment start. Secondary endpoints were overall survival (OS), complete response rates, toxicity, quality of life, and minimal residual disease (MRD) response with protocol defined visits up to month 30. For the primary endpoint, PFS at 2 years was 85% for the intention-to-treat set. Long-term data were captured in selected sites and evaluated as post hoc analysis in the per protocol (PP) set: PFS and OS were 78% and 96% at 5 years with a median follow-up of 66 or 78 months, respectively. There were 17/76 recurrences in the PP set, of which 14 were outside the radiation volume only. MRD analyses revealed a clonal marker in 36% of patients at diagnosis. All but 1 marker positive patients experienced a molecular treatment response. There were 13 serious adverse events (4 related to the therapy) during the first 30 months. IF radiotherapy combined with Rituximab is well tolerated and highly efficient with low rates of recurrence in the first years in early-stage FL. The efficacy is comparable with more aggressive therapy approaches without compromising the quality of life and maintains for an extended follow-up of more than 5 years.

Where to start? Upfront therapy for follicular lymphoma in 2018

The initial approach to the management of follicular lymphoma (FL) is challenging for patients and physicians. Most FL patients present with minimal symptoms; given the lack of a survival benefit to early treatment in this population, a period of observation without therapy is often appropriate. Once there is disease progression beyond low-tumor-burden criteria or symptoms prompting intervention, patients may be considered for an array of potential treatment options. These range from single-agent rituximab (anti-CD20) to various forms of chemoimmunotherapy, including rituximab or the newer anti-CD20 monoclonal antibody obinutuzumab. Unfortunately, prognostic and other clinical factors are of limited value in guiding optimal selection of therapy. Once patients complete initial treatment and achieve a complete or a partial remission, the next decision relates to the pros and cons of maintenance anti-CD20 therapy. Maintenance antibody administration can improve progression-free, but not overall, survival; hence, patient preferences typically drive this decision. Monitoring after remission is achieved should generally be guided by symptoms, physical examination, and laboratory findings, with routine surveillance imaging discouraged in the absence of new clinical issues. Given the wide range of options available and the importance of optimizing quality of life in this chronic health condition, education and shared decision making are pillars in the upfront management of FL to help patients achieve the best possible outcomes.

Cause of Death in Follicular Lymphoma in the First Decade of the Rituximab Era: A Pooled Analysis of French and US Cohorts

PURPOSE

Although the life expectancy of patients with follicular lymphoma (FL) has increased, little is known of their causes of death (CODs) in the rituximab era.

PATIENTS AND METHODS

We pooled two cohorts of newly diagnosed patients with FL grade 1-3A. Patients were enrolled between 2001 and 2013 in two French referral institutions (N = 734; median follow-up 89 months) and 2002 and 2012 in the University of Iowa and Mayo Clinic Specialized Program of Research Excellence (SPORE; N = 920; median follow-up 84 months). COD was classified as being a result of lymphoma, other malignancy, treatment related, or all other causes.

RESULTS

Ten-year overall survival was comparable in the French (80%) and US (77%) cohorts. We were able to classify COD in 248 (88%) of 283 decedents. In the overall cohort, lymphoma was the most common COD, with a cumulative incidence of 10.3% at 10 years, followed by treatment-related mortality (3.0%), other malignancy (2.9%), other causes (2.2%), and unknown (3.0%). The 10-year cumulative incidence of death as a result of lymphoma or treatment was higher than death as a result of all other causes for each age group (including patients ≥ 70 years of age at diagnosis [25.4% v 16.6%]) Follicular Lymphoma International Prognostic Index score 3 to 5 (27.4% v 5.2%), but not Follicular Lymphoma International Prognostic Index score 0 to 1 (4.0% v 3.7%); for patients who failed to achieve event-free survival within 24 months from diagnosis (36.1% v 7.0%), but not for patients who achieved event-free survival within 24 months of diagnosis (6.7% v 5.7%); and for patients with a history of transformed FL (45.9% v 4.7%), but not among patients without (8.1% v 6.2%). Overall, 77 of 140 deaths as a result of lymphoma occurred in patients whose FL transformed after diagnosis.

CONCLUSION

Despite the improvement in overall survival in patients with FL in the rituximab era, their leading COD remains lymphoma, especially after disease transformation. Treatment-related mortality also represents a concern, which supports the need for less-toxic therapies.

Beyond maximum grade: modernising the assessment and reporting of adverse events in haematological malignancies

Tremendous progress in treatment and outcomes has been achieved across the whole range of haematological malignancies in the past two decades. Although cure rates for aggressive malignancies have increased, nowhere has progress been more impactful than in the management of typically incurable forms of haematological cancer. Population-based data have shown that 5-year survival for patients with chronic myelogenous and chronic lymphocytic leukaemia, indolent B-cell lymphomas, and multiple myeloma has improved markedly. This improvement is a result of substantial changes in disease management strategies in these malignancies. Several haematological malignancies are now chronic diseases that are treated with continuously administered therapies that have unique side-effects over time. In this Commission, an international panel of clinicians, clinical investigators, methodologists, regulators, and patient advocates representing a broad range of academic and clinical cancer expertise examine adverse events in haematological malignancies. The issues pertaining to assessment of adverse events examined here are relevant to a range of malignancies and have been, to date, underexplored in the context of haematology. The aim of this Commission is to improve toxicity assessment in clinical trials in haematological malignancies by critically examining the current process of adverse event assessment, highlighting the need to incorporate patient-reported outcomes, addressing issues unique to stem-cell transplantation and survivorship, appraising challenges in regulatory approval, and evaluating toxicity in real-world patients. We have identified a range of priority issues in these areas and defined potential solutions to challenges associated with adverse event assessment in the current treatment landscape of haematological malignancies.

Chemotherapy-Free Initial Treatment of Advanced Indolent Lymphoma Has Durable Effect With Low Toxicity: Results From Two Nordic Lymphoma Group Trials With More Than 10 Years of Follow-Up

PURPOSE

For indolent lymphoma, the optimal timing, sequence, and choice of therapeutic regimens remain a matter of debate. In two Nordic Lymphoma Group randomized trials, symptomatic or clearly progressing patients were treated first line with a rituximab-containing regimen without chemotherapy. The purpose of this study was to assess long-term survival, risk of transformation, and need of new therapies.

METHODS

Data were collected at cross-sectional follow-up for 321 patients with indolent lymphoma (84% with follicular lymphomas [FL]) included in one of two Nordic Lymphoma Group trials (accrual 1998 to 1999 and 2002 to 2008). All patients received first-line therapy with one or two cycles of four weekly infusions of rituximab 375 mg/m2, and 148 were randomly allocated to the addition of interferon alfa-2a. Follow-up data were retrieved from initial trial databases and medical records on repeated clinical evaluations.

RESULTS

At the end of follow-up, 73% of patients were alive, with a median follow-up after random assignment of 10.6 years. Among all, 36% (38% with FL) had never needed chemotherapy. For patients with FL who required new therapy within 24 months because of early disease progression, the 10-year survival rate was 59% versus 81% for those with longer remission. Interferon was not shown to improve long-term outcome. Transformation was diagnosed in 20% of all patients (2.4% per person-year) and in 18% with FL. An additional malignancy was found in 12%.

CONCLUSION

Approximately one third of patients with symptomatic indolent lymphoma (30% with FL, 23% without FL) did not need new therapy in the long term after first-line rituximab without chemotherapy. In the entire cohort, 10-year survival was excellent with no major safety issues, which suggests that chemotherapy can be delayed safely in the majority of patients.

A Generic Model for Follicular Lymphoma: Predicting Cost, Life Expectancy, and Quality-Adjusted-Life-Year Using UK Population-Based Observational Data

OBJECTIVES

To use real-world data to develop a flexible generic decision model to predict cost, life expectancy, and quality-adjusted life-years (QALYs) for follicular lymphoma (FL) in the general patient population.

METHODS

All patients newly diagnosed with FL in the UK's population-based Haematological Malignancy Research Network (www.hmrn.org) between 2004 and 2011 were followed until 2015 (N = 740). Treatment pathways, QALYs, and costs were incorporated into a discrete event simulation to reflect patient heterogeneity, including age and disease management. Two scenario analyses, based on the latest National Institute for Health and Clinical Excellence (NICE) guidelines (rituximab induction therapy for newly diagnosed asymptomatic patients and rituximab maintenance therapy for patients between treatments), were conducted and their economic impacts were compared to current practice.

RESULTS

Incidence-based analysis revealed expected average lifetime costs ranging from £6,165 [US$7,709] to £63,864 [US$79,862] per patient, and average life expectancy from 75 days to 17.56 years. Prevalence-based analysis estimated average annual treatment costs of £60-65 million [US$75-80 million], accounting for approximately 10% of the United Kingdom's annual National Health Service budget for hematological cancers as a whole. Assuming that treatment effects reported in trials are applicable to all patient groups, scenario analyses for two recent NICE guidelines demonstrated potential annual cost savings for the United Kingdom that ranged with uptake frequency from £0.6 million to £11 million [US$0.75-2.75 million].

CONCLUSIONS

Costs, survival, and QALYs associated with FL vary markedly with patient characteristics and disease management. Allowing the production of more realistic outcomes across the patient population as a whole, our model addresses this heterogeneity and is a useful tool with which to evaluate new technologies/treatments to support healthcare decision makers.

What is the significance of monoclonal gammopathy of undetermined significance?

Monoclonal gammopathy of undetermined significance (MGUS) is characterised by the presence of a monoclonal paraprotein in the blood, without the characteristic end organ damage seen in multiple myeloma. MGUS is more common in older age groups and has a risk of progression to myeloma of 1% per year. Population screening is not currently recommended, but retrospective studies have suggested improvements in myeloma outcomes in those under MGUS follow-up; in addition, MGUS has associated complications, including fracture, osteoporosis, renal disease and infection, which can be treated. Given this increasing evidence of disease related directly to MGUS, strategies for early identification might be needed. In this review, we discuss the complications of MGUS and whether MGUS fulfils the criteria needed to implement a screening programme. We also highlight areas where more evidence is needed, including identification of a higher risk population to make screening more practical and economically viable.

In Situ Vaccination with a TLR9 Agonist and Local Low-Dose Radiation Induces Systemic Responses in Untreated Indolent Lymphoma

This multicenter phase I/II clinical trial evaluated intratumoral SD-101, a TLR9 agonist, and low-dose radiation in patients with untreated indolent lymphoma. Twenty-nine enrolled patients received 4 Gy of radiation followed by 5 weekly intratumoral injections of SD-101 at a single tumor site. No treatment-related grade 4 or serious adverse events occurred. Nearly all patients had tumor reduction at their treated site. More importantly, 24 patients had tumor reduction at their nontreated sites, with 5 patients achieving a partial response and one achieving a complete response. Treatment-related increases of CD8+ and CD4+ effector T cells and decreases of T follicular helper and T regulatory cells (Treg) were observed in the tumor microenvironment. Low pretreatment levels of CD4+ Tregs, proliferating CD8+ T cells, and Granzyme B+ CD8+ T cells were associated with favorable outcomes. Intratumoral SD-101 in combination with low-dose radiation is well tolerated and results in regression of both treated and untreated sites of disease.Significance: In situ vaccination with the TLR9 agonist SD-101, along with low-dose radiation, was safe and induced systemic responses in patients with indolent lymphoma. Low levels of CD4+ Tregs, proliferating CD8+ T cells, and Granzyme B+ CD8+ T cells in the tumor microenvironment predicted favorable response to treatment. Cancer Discov; 8(10); 1258-69. ©2018 AACR. This article is highlighted in the In This Issue feature, p. 1195.

Biosimilars in oncology and inflammatory diseases: current and future considerations for clinicians in Latin America

Biological therapies have revolutionized the treatment of several cancers and systemic immune-mediated inflammatory conditions. Expiry of patents protecting a number of biologics has provided the opportunity to commercialize highly similar versions, known as biosimilars. Biosimilars are approved by regulatory agencies via an independent pathway that requires extensive head-to-head comparison with the originator product. Biosimilars have the potential to provide savings to healthcare systems and expand patient access to biologics. In Latin American countries, regulatory frameworks for biosimilar approval have been introduced in recent years, and biosimilars of monoclonal antibody and fusion protein therapies are now emerging. However, the situation in this region is complicated by the presence of "non-comparable biotherapeutics" (also known as "intended copies"), which have not been rigorously compared with the originator product. We review the considerations for clinicians in Latin American countries, focusing on monoclonal antibody biosimilars relevant to oncology, rheumatology, gastroenterology, and dermatology.

Spotlight on copanlisib and its potential in the treatment of relapsed/refractory follicular lymphoma: evidence to date

The importance of the phosphatidylinositol-3-kinase (PI3K) pathway in cell survival and proliferation has made it an attractive target in cancer therapy. The development of small molecule inhibitors for the PI3K pathway continues to provide treatment alternatives across a range of malignancy types. Several agents, including idelalisib, copanlisib and duvelisib, not only inhibit the PI3K pathway, but also have effects on associated mechanisms including the ATK and mTOR pathways. The advent of PI3K-specific small molecular inhibitors has led to increased efficacy with avoidance of an excessive toxicity profile. Key enzymes of the PI3K pathway exhibit differing expression in tissue types and roles in tumor pathogenesis. Copanlisib (BAY 80-6946) is a pan-specific PI3K small molecule inhibitor for four key isoforms with increased activity against PI3Kα and PI3Kδ, both important in B-cell malignancies. Follicular lymphoma is one of the most common indolent B-cell non-Hodgkin lymphomas worldwide. Follicular lymphoma like other indolent B-cell non-Hodgkin lymphomas is beleaguered by high relapse rates and the need for subsequent therapy options. Based on efficacy and a limited toxicity profile, copanlisib received accelerated US Food and Drug Administration approval for the treatment of adult patients with relapsed follicular lymphoma following two lines of therapy. Here, we review the development of copanlisib and the role of this agent in the treatment of follicular lymphoma.

Watch-and-wait policy versus rituximab-combined chemotherapy in Japanese patients with intestinal follicular lymphoma

BACKGROUND AND AIM

Few reports have demonstrated the effectiveness of treatments for intestinal follicular lymphoma (FL) because of the limited number of patients who undergo comprehensive small intestinal examinations. This study compared the efficacy of rituximab-combined chemotherapy in patients with asymptomatic and low tumor burden (LTB) intestinal FL, according to the criteria of the Groupe d'Etude des Lymphomes Folliculaires, with that of a "watch and wait" (W&W) approach.

METHODS

The endoscopic examination for entire gastrointestinal tracts was performed in 29 Japanese patients with intestinal FL. These patients had CD21-positive follicular dendritic cells arranged in a duodenal pattern. In a prospective, two-center, open-label trial, this study evaluated the efficacy of rituximab-combined chemotherapy ([cyclophosphamide, doxorubicin, vincristine, and prednisone] or [cyclophosphamide, vincristine, and prednisone]) and prolonged treatment with rituximab (R-Chemo+prolongedR) in 14 patients and compared their outcomes with those of 15 patients managed with a W&W approach.

RESULTS

Four patients managed with the W&W plan showed worsening macroscopic findings, lesion area enlargement, or clinical stage progression but stayed on this plan because they had LTB and experienced no changes in bowel function. In the R-Chemo+prolongedR group, all patients achieved complete remission; recurrence occurred in one patient, who was subsequently managed with the W&W plan because of LTB. There were no significant differences in progression-free survival between the two groups (P = 0.1045). Overall survival was 100% in both groups.

CONCLUSIONS

The prognoses of patients with asymptomatic intestinal FL and LTB who were managed with a W&W strategy were comparable with those of patients receiving R-Chemo+prolongedR.

An update in treating transformed lymphoma

Indolent lymphomas typically have a prolonged course and favorable prognosis. Recent data support survival times that can reach several decades, even if periodic treatment is needed to manage symptoms or stabilize disease. However, all indolent lymphomas have the potential to undergo transformation to an aggressive phenotype, clinically characterized by a rapid progression of adenopathy, new-onset constitutional symptoms, or laboratory abnormalities, and the immediate need for therapeutic intervention. The most common scenario is transformation of follicular lymphoma to either diffuse large B-cell lymphoma or high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 translocations; however, other indolent subtypes such as marginal zone lymphoma, lymphoplasmacytic lymphoma, small lymphocytic lymphoma/chronic lymphocytic leukemia, or even nodular lymphocyte predominant Hodgkin lymphoma, can undergo similar histologic transformation. The prognosis of transformed lymphomas has historically been quite poor, but there is ample evidence this is changing in the rituximab era. This article will provide a review of transformed lymphomas with an emphasis on treatment and the nuances of diagnosis and clinical management. Unless otherwise specified, all discussion in this review pertains to transformed follicular lymphoma which is the more common scenario and the subtype with the most robust data. In many cases, this information can be extrapolated and applied to other indolent histologies (i.e. transformed marginal zone lymphoma); however, several other clinical scenarios, such as Richter's transformation and "double hit" transformations, warrant a distinct discussion and will be reviewed separately.

90 Y-ibritumomab-tiuxetan as a therapeutic alternative for follicular lymphoma (FL): A single-center experience

BACKGROUND

Follicular lymphoma (FL) is the most frequent indolent lymphoma subtype in adults. Maintenance therapy with rituximab is frequently applied to FL patients with complete or partial response following initial chemoimmunotherapy. However, radioimmunotherapy with ⁹⁰ Y-ibritumomab-tiuxetan represents a therapeutic alternative.

METHODS

To compare the clinical and the prognostic impact of both therapies, a study collective of n = 56 patients diagnosed with indolent B-cell lymphoma was retrospectively investigated. The study collective was subdivided into two groups: n = 36 patients treated with rituximab maintenance therapy vs n = 20 patients treated with ⁹⁰ Y-ibritumomab-tiuxetan.

RESULTS

No prognostic differences for performance status, FLIPI score, gender, or B-symptoms were found for ⁹⁰ Y-ibritumomab-tiuxetan or rituximab maintenance therapy. Overall survival rates and progression-free survival did not differ between both maintenance therapies.

CONCLUSION

Our retrospective single-center analysis of two patient groups without major differences in prognostic parameters revealed similar outcome with two different maintenance therapies. Hence, ⁹⁰ Y-ibritumomab-tiuxetan therapy might offer a valuable alternative treatment option for FL patients with partial response. However, large prospective trials are needed to confirm the reported findings.

Tolerability of obinutuzumab therapy in patients with rituximab-relapsed/refractory B-cell malignancies - a retrospective single center cohort study

BACKGROUND & AIM

In randomised clinical trials, the type II anti-CD20 antibody obinutuzumab has been shown to be more effective than rituximab for therapy of chronic lymphocytic leukemia (CLL) and follicular lymphoma (FL). However, this enhanced efficacy was linked with elevated rates of high-grade adverse events. The aim of this study was to assess the tolerability and toxicity profile of obinutuzumab treatment in routine patients with CLL and FL, of whom the majority had experienced toxicity or resistance to rituximab.

METHODS

This retrospective cohort study investigated fifteen obinutuzumab-treated patients, eight with CLL and seven with FL. The course of the disease, comorbidities and treatment-related toxicities were recorded. All patients with CLL and all but three FL patients had any form of pre-treatment with rituximab.

RESULTS

Between October 2014 and August 2017, 15 patients were treated with obinutuzumab at the University Hospital Krems. In the CLL-cohort, 1 patient (12,5%) developed pneumonia, 2 (25%) febrile neutropenia, 6 (75%) anemia and 7 (87,5%) thrombocytopenia, respectively. One patient exhibited an infusion-related allergic reaction. In the FL-cohort, 6 patients (85,7%) presented with thrombocytopenia, 3 (42,9%) with anemia and one patient with neutropenia. No sepsis or consecutive solid tumors were seen in any of the patients.

CONCLUSION

Obinutuzumab was mostly well tolerated in mild to heavily pre-treated patients with CLL and therapy-naïve or pre-treated patients with FL. The frequency and profile of adverse events and toxicity was comparable to data from previous clinical studies and could be managed adequately in the setting of a University Clinic.

Current and future therapeutic approaches for the treatment of follicular lymphoma

INTRODUCTION

Recent advances in prognostication as well as management of Follicular Lymphoma (FL) are moving to personalized approach. Areas covered: Prognostic scores as well as consolidated and innovative therapeutic approaches are evaluated according to the various presentation modalities. For asymptomatic, low-tumor burden FL, a 'watch and wait' policy is currently the first-choice approach, although possible alternatives are discussed. Early stage FL may be treated with local radiotherapy although the role of minimal residual disease in possible additional agents should be determined. The first line treatment for symptomatic FL is chemo-immunotherapy followed by two years maintenance therapy with anti-CD20 monoclonal antibodies. A deeper knowledge of FL biology has opened new perspectives regarding the timing of therapy and has offered new targets for the development of novel agents that aim to change the therapeutic scenario of FL management. Expert commentary: The introduction of novel agents could question the incurability of FL and change the therapeutic goal from prolonging the complete remission state to eradicating the disease in young/fit patients, as well as improving quality of life in elderly/unfit patients. In the near future, combining new biologic agents and adoptive cell therapies could help in achieving these aims.

Targeting the B-cell receptor pathway: a review of current and future therapies for non-Hodgkin's lymphoma

INTRODUCTION

The B-cell receptor (BCR) pathway is a crucial aspect of mature lymphocytes and is maintained in B-cell neoplasms. Many small module inhibitors targeting kinases within the BCR pathway are approved, with others in development, offering alternative treatment options to standard chemoimmunotherapy. Areas covered: This review covers both approved inhibitors and investigational inhibitors of spleen tyrosine kinase (SYK), Bruton's tyrosine kinase (BTK), and phosphoinositide-3-kinase (PI3K) in the treatment of B-cell lymphomas. To collect relevant articles, a literature search was completed through the use of PubMed and abstracts from ASH and ASCO national meetings. Search terms including non-Hodgkin lymphoma, and BCR inhibitors, as well as the individual drug names, were utilized. The majority of included studies are dated from 2012 to March 2018. Expert opinion: BCR pathway inhibitors, such as ibrutinib and idelalisib, are novel treatments for non-Hodgkin lymphomas. While providing alternative treatment options to those with high-risk disease, poor functional status, and relapsed disease, outside of chronic lymphocytic leukemia (CLL), they have been limited to the relapsed/refractory setting. Their mechanisms of action, off/on-target effects, and resistance patterns create unique therapeutic dilemmas. It is our opinion that more specific inhibitors, as well as combination therapy, will define the future for BCR inhibitors.

Past, Present, and Future of Rituximab-The World's First Oncology Monoclonal Antibody Therapy

Rituximab is a chimeric mouse/human monoclonal antibody (mAb) therapy with binding specificity to CD20. It was the first therapeutic antibody approved for oncology patients and was the top-selling oncology drug for nearly a decade with sales reaching $8.58 billion in 2016. Since its initial approval in 1997, it has improved outcomes in all B-cell malignancies, including diffuse large B-cell lymphoma, follicular lymphoma, and chronic lymphocytic leukemia. Despite widespread use, most mechanistic data have been gathered from in vitro studies while the roles of the various response mechanisms in humans are still largely undetermined. Polymorphisms in Fc gamma receptor and complement protein genes have been implicated as potential predictors of differential response to rituximab, but have not yet shown sufficient influence to impact clinical decisions. Unlike most targeted therapies developed today, no known biomarkers to indicate target engagement/tumor response have been identified, aside from reduced tumor burden. The lack of companion biomarkers beyond CD20 itself has made it difficult to predict which patients will respond to any given anti-CD20 antibody. In the past decade, two new anti-CD20 antibodies have been approved: ofatumumab, which binds a distinct epitope of CD20, and obinutuzumab, a mAb derived from rituximab with modifications to the Fc portion and to its glycosylation. Both are fully humanized and have biological activity that is distinct from that of rituximab. In addition to these new anti-CD20 antibodies, another imminent change in targeted lymphoma treatment is the multitude of biosimilars that are becoming available as rituximab's patent expires. While the widespread use of rituximab itself will likely continue, its biosimilars will increase global access to the therapy. This review discusses current research into mechanisms and potential biomarkers of rituximab response, as well as its biosimilars and the newer CD20 binding mAb therapies. Increased ability to assess the effectiveness of rituximab in an individual patient, along with the availability of alternative anti-CD20 antibodies will likely lead to dramatic changes in how we use CD20 antibodies going forward.