The landscape of T-cell engagers for the treatment of follicular lymphoma.

Follicular lymphoma (FL), the second most common subtype of non-Hodgkin lymphoma, relies on interactions with immune elements in the tumor microenvironment, including T-follicular helper cells and follicular dendritic cells, for its survival and progression. Despite its initial responsiveness to chemoimmunotherapy, FL is generally considered incurable. Strategies to improve immune-mediated control of FL could significantly benefit this population, particularly as it includes many elderly and comorbid patients. Immune cell engagers, especially bispecific antibodies (BsAbs), are crucial in targeting FL by bridging tumor and effector cells, thereby triggering T-cell activation and cytotoxic killing. CD3 × CD20 BsAbs have shown the most promise in clinical development for B-NHL patients, with structural variations affecting their target affinity and potency. This review summarizes the current clinical trials of BsAbs for relapsed/refractory FL, highlighting the approval of some agents, their role in first-line treatment or combination therapies, their toxicity profiles, and the future of this therapeutic approach compared to other immune cell therapies.

[Current standard treatments and future outlook for follicular lymphoma].

Follicular lymphoma (FL) is the most common subtype of indolent lymphoma. Survival outcomes for FL have improved since the introduction of anti-CD20 monoclonal antibodies, such as rituximab, and median overall survival has reached 15-20 years. However, FL is an incurable disease that subsequently progresses or relapses, and progression-free and overall survival tend to shorten with repeated relapses. For patients with limited-stage disease, radiation therapy is generally the treatment of choice and results in a median survival of approximately nearly 20 years. For advanced-stage patients with low tumor burden, watchful waiting continues to be the appropriate strategy at present. It remains unclear whether rituximab monotherapy might change this watchful waiting approach and result in a benefit from early intervention in patients with low tumor burden. For advanced-stage patients with high tumor burden, chemoimmunotherapy including rituximab or obinutuzumab followed by maintenance therapy is the standard treatment. For relapsed or refractory patients, treatment options such as chemoimmunotherapy, lenalidomide-rituximab, tazemetostat, chimeric antigen receptor T-cell therapies, and CD3/CD20 bispecific antibodies are available or in development. This review presents current standard treatments, recent advances, and future perspectives on the management of FL.

[Chinese expert consensus on the diagnosis and management of elderly patients with follicular lymphoma (2024)].

In the general population of China, the number of older patients with follicular lymphoma (FL) will continue to increase with age. The treatment of elderly patients with FL is based on individual principles, which focuses on the improvement of tumor-related symptoms and quality of life. To improve the diagnosis and treatment of elderly patients with FL in China, several organizations (i.e., Hematology Oncology Committee of China Anti-Cancer Association, etc.) have gathered relevant experts to formulate this consensus.

Recent developments in CD19-targeted therapies for follicular lymphoma.

INTRODUCTION: CD19 has emerged as an important and novel therapeutic target in follicular lymphoma. CD19-directed therapies, including monoclonal antibodies, bispecific antibodies, and CAR T-cell therapies, offer promising avenues for treating follicular lymphoma and improving outcomes. AREAS COVERED: We review the role and rationale of targeting CD19 in follicular lymphoma and different interventions of CD19 targeting, such as cell therapy, bispecific antibodies, antibody-drug conjugates, and monoclonal antibodies. We finalize with a discussion on how these therapies may influence the treatment landscape of follicular lymphoma. EXPERT OPINION: CD19 is an attractive target for therapeutic development in follicular lymphoma. Given its effectiveness, it will continue to move forward as a promising therapy for this disease.

Follicular Lymphoma in Chile in the Adult Public Cancer Program: The Impact of Chemoimmunotherapy.

BACKGROUND: Follicular lymphoma (FL) is the most common indolent non-Hodgkin lymphoma (NHL) in the United States and Europe. However, data on FL from Latin America are scant. AIMS: This study aims at better understand the clinical features, treatment patterns and outcomes of patients with FL in Chile. Of special interest was to evaluate POD24 as an adverse marker. METHODS AND RESULTS: We collected retrospective data from 722 patients 15 years or older diagnosed with FL and treated in 17 cancer centers in Chile between 2000 and 2019. Time to first treatment (TTFT), progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Cox proportional-hazard regression models were fitted to investigate prognostic factor. The median age at diagnosis was 62 with a female predominance (63%); 73% of patients had advance stage disease and 68% had bone marrow involvement; 63% had intermediate or high FLIPI scores. The 1-year TTFT rate was 96%, and 30% of patients received chemoimmunotherapy. Adding rituximab to chemotherapy was associated with a higher complete response (69% vs. 60%; p < 0.001) and superior median OS (16 vs. 8 years; p < 0.001). Patients who experience POD24 had an inferior median OS (2.4 vs. 15 years). CONCLUSION: Our study shows a female predominance in patients with FL in Chile and confirms superior response and survival outcomes with adding rituximab to chemotherapy. Our study also confirms a poor OS in patients who experience POD24.

Transformed follicular lymphoma with laryngeal edema requiring tracheal intubation after tisagenlecleucel treatment: A case report.

RATIONALE: Cytokine release syndrome (CRS) is a common adverse event of chimeric antigen receptor T (CAR-T) cell therapy. CRS is generally a systemic inflammatory reaction, but in rare cases, it can occur in specific body areas and is referred to as "local CRS (L-CRS)." A case of laryngeal edema due to L-CRS that required tracheal intubation because of the lack of response to tocilizumab (TCZ) and dexamethasone (DEX) is reported. PATIENT CONCERNS: A 67-year-old woman with relapsed transformed follicular lymphoma was treated with CAR-T cell therapy. Although she had been given TCZ and DEX for CRS, neck swelling appeared on day 4 after infusion. DIAGNOSES: Laryngoscopy showed severe laryngeal edema, which was presumed to be due to L-CRS, since there were no other apparent triggers based on history, physical examination, and computed tomography. INTERVENTIONS: Tracheal intubation was performed because of the risk of upper airway obstruction. Ultimately, 4 doses of tocilizumab (8 mg/kg) and 6 doses of dexamethasone (10 mg/body) were required to improve the L-CRS. OUTCOMES: On day 7, laryngeal edema improved, and the patient could be extubated. LESSONS: The lessons from this case are, first, that CAR-T cell therapy may induce laryngeal edema in L-CRS. Second, TCZ alone may be ineffective in cervical L-CRS. Third, TCZ, as well as DEX, may be inadequate. In such cases, we should recognize L-CRS and manage it early because it may eventually progress to laryngeal edema that requires securing the airway.

Duodenal-type follicular lymphoma: comprehensive insights into disease characteristics and established treatment strategies.

PURPOSE OF REVIEW: This review aims to detail the characteristics and outcomes of duodenal-type follicular lymphoma (DTFL), a rare lymphoma variant. It focuses on integrating recent reports in treatment modalities and highlights emerging insights into the unique biological features of the disease. RECENT FINDING: Recent studies confirm the indolent nature of DTFL, with extended follow-up periods showing favorable outcomes under watchful waiting strategies and a notable proportion of patients experiencing spontaneous remission. Additionally, advancements in understanding the disease's biology revealed that the tumor microenvironment is marked by specific genomic expressions indicative of chronic inflammation. SUMMARY: The observations of spontaneous resolution and the generally favorable progression of DTFL call for a conservative approach in initiating treatment. Clinical management should judiciously consider the disease's typically benign course against the potential risks of intervention, promoting customized treatment protocols tailored for cases with clinical necessity. Additionally, the discovery of an inflammatory tumor microenvironment and molecular evidence suggesting an antigen-driven process highlight critical areas for future research.

Diagnosis, management and follow-up of follicular lymphoma: a consensus practice statement from the Australasian Lymphoma Alliance.

Follicular lymphoma (FL) is the most common indolent non-Hodgkin lymphoma subtype, accounting for 15-20% of all lymphoma diagnoses. Although typically slow-growing and responsive to frontline therapies, advanced-stage FL remains incurable with current treatments and typically follows a chronic relapsing/remitting course with increasingly shorter responses to subsequent lines of therapy. Outcomes are highly variable; some patients experience prolonged first remissions that may approximate a 'functional cure'. By contrast, a significant minority of patients experience disease progression shortly after frontline treatment resulting in high rates of lymphoma-related mortality. Reflecting on the heterogeneous natural history of FL, clinical practice varies widely, particularly in controversial areas, including appropriate disease staging, selection of management strategies and duration of clinical follow-up. This position statement presents an evidence-based synthesis of the literature for application in Australasian practice.

Prolonged water-only fasting in the management of low-grade follicular lymphoma: a case series.

BACKGROUND: Follicular lymphoma typically follows an indolent and relapsing course often requiring several treatment cycles to achieve remission. Some patients opt to use complementary and alternative therapies particularly when observation is a treatment option. CASE PRESENTATION: Here we present a case series of three patients, a 50-year-old, White, Hispanic female, 56-year-old, White, non-Hispanic male, and 49-year-old, White, non-Hispanic male, who elected to undergo one or more prolonged water-only fasting and refeeding interventions to manage low to intermediate grade follicular lymphoma. Fasting was well tolerated in each patient. Each patient also experienced a reduction in the size and avidity of hypermetabolic lymph nodes as independently determined by their respective oncologists. CONCLUSION: The reported cases demonstrate positive outcomes in low-grade follicular lymphoma coinciding with prolonged water-only fasting and exclusively whole-plant-food dietary interventions. These findings highlight the potential of such interventions and warrant further exploration through preliminary observational research.

Recent updates on treatment options for primary follicular lymphoma of the gastrointestinal tract.

BACKGROUND: Primary gastrointestinal follicular lymphoma is a subtype of follicular lymphoma that originates directly from the gastrointestinal tract. Pathologically, it exhibits substantial similarities with the secondary gastrointestinal involvement observed in nodal follicular lymphoma. However, primary gastrointestinal follicular lymphoma presents clinically distinct features, necessitating divergent considerations in treatment selection compared with nodal follicular lymphoma. AREAS COVERED: This narrative review focused on recent articles (2018-2023) regarding the long-term prognosis and treatment options for gastrointestinal follicular lymphoma. In addition, a brief overview of gastrointestinal follicular lymphomas is provided. EXPERT OPINION: Patients with primary gastrointestinal follicular lymphoma often present with a low tumor burden. Lymphoma lesions typically remain asymptomatic for several years or may undergo spontaneous regression without immediate treatment. Therefore, a 'watch and wait' approach is justified. Conversely, when large tumor masses are identified in the gastrointestinal tract, the potential for tumor bleeding or intestinal obstruction requires timely therapeutic interventions.

Clinical Practice Recommendations for Hematopoietic Cell Transplantation and Cellular Therapies in Follicular Lymphoma: A Collaborative Effort on Behalf of the American Society for Transplantation and Cellular Therapy and the European Society for Blood and Marrow Transplantation.

Follicular lymphoma (FL) is the most common indolent B-cell non-Hodgkin lymphoma (NHL), accounting for nearly one-third of all NHL. The therapeutic landscape for patients with FL has significantly expanded over the past decade, but the disease continues to be considered incurable. Hematopoietic cell transplantation (HCT) is potentially curative in some cases. Recently, the emergence of chimeric antigen receptor T-cell therapy (CAR-T) for patients with relapsed/refractory (R/R) FL has yielded impressive response rates and long-term remissions, but definitive statement on the curative potential of CAR-T is currently not possible due to limited patient numbers and relatively short follow up. A consensus on the contemporary role, optimal timing, and sequencing of HCT (autologous or allogeneic) and cellular therapies in FL is needed. As a result, the American Society of Transplantation and Cellular Therapy (ASTCT) Committee on Practice Guidelines endorsed this effort to formulate consensus recommendations to address this unmet need. The RAND-modified Delphi method was used to generate 15 consensus statements/recommendations. These clinical practice recommendations will help guide clinicians managing patients with FL. Of note, the use of bispecific antibodies in R/R FL was not in the scope of this project.

Risk of transformation by frontline management in follicular and marginal zone lymphomas: a US population-based analysis.

ABSTRACT: Follicular lymphoma (FL) and marginal zone lymphoma (MZL) often have long overall survival (OS), however, high-grade transformation (HGT) to diffuse large B-cell lymphoma markedly reduces survival. The roles of upfront treatment vs observation on the incidence and outcome of HGT remain unclear. Thus, we analyzed a Surveillance, Epidemiology, and End Results database to address this question. Patients diagnosed with FL grades 1 to 2 or MZL between 2000 and 2020 were included. Fine-Gray models estimated the impact of covariates on HGT cumulative incidence and lymphoma-specific survival (LSS) and Cox regression on OS. HGT occurred in 4.2% of 23 384 patients with FL and 2.5% of 20 530 patients with MZL. The 5- and 10-year HGT cumulative incidence rates were 2.80% and 4.87% for FL, and 1.74% and 2.95% for MZL, respectively, which are notably lower than in earlier studies. The annual HGT incidence rate peaked in the first 2 years, then steadily declined over 2 decades for FL and all MZL subtypes. In FL, upfront observation vs treatment increases HGT risk (sub-distribution hazard ratio [SHR], 1.23; 95% confidence interval [CI], 1.09-1.40; P < .001) and barely affects OS (hazard ratio [HR], 0.95; 95% CI, 0.90-0.99; P = .03). Conversely, upfront observation was associated with lower HGT risk in nodal (SHR, 0.71; 95% CI, 0.53-0.94; P = .01) and extranodal (SHR, 0.64; 95% CI, 0.48-0.86; P = .003) MZL and did not affect survival in extranodal disease (HR, 0.94; 95% CI, 0.97-1.02; P = .15). HGT was associated with decrease in LSS across all histologies. Upfront treatment reduced the risk of HGT only in FL but not MZL.

Long-Term Remission with Novel Combined Immune-Targeted Treatment for Histiocytic Sarcoma Accompanied by Follicular Lymphoma: Case Report and Literature Review.

Histiocytic sarcoma (HS) is an extremely rare but aggressive hematopoietic malignancy, and the prognosis has been reported to be rather unfavorable with a median overall survival of merely 6 months. We presented a 58-year-old female patient complaining of abdominal pain and fever, who was admitted to our institution in September 2021. Fluorine-18-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) scan showed enlargement of generalized multiple lymph nodes. Subsequently, laparoscopic retroperitoneal lesion biopsy and bone marrow aspiration were performed. The pathological findings indicated the diagnosis of HS concurrent with follicular lymphoma. The immunohistochemistry (IHC) staining of the tumor lesion revealed a high expression of CD38 and PD-L1 proteins. Furthermore, KRAS gene mutation was identified by means of next-generation sequencing. The patient exhibited poor treatment response to both first- and second-line cytotoxic chemotherapies. Therefore, she underwent six cycles of Daratumumab (anti-CD38 monoclonal antibody), Pazopanib (multi-target receptor tyrosine kinases inhibitor) combined with third-line chemotherapy, followed by involved-site radiotherapy and maintenance therapy with the PD-1 inhibitor Tislelizumab. Long-term partial remission was finally achieved after multi-modality treatment. Duration of remission and overall survival reached 22 and 32 months, respectively. Our case indicated that immuno-targeted treatment coupled with chemotherapy and radiotherapy might constitute a potential therapeutic option for HS.

Lisocabtagene maraleucel in follicular lymphoma: the phase 2 TRANSCEND FL study.

An unmet need exists for patients with relapsed/refractory (R/R) follicular lymphoma (FL) and high-risk disease features, such as progression of disease within 24 months (POD24) from first-line immunochemotherapy or disease refractory to both CD20-targeting agent and alkylator (double refractory), due to no established standard of care and poor outcomes. Chimeric antigen receptor (CAR) T cell therapy is an option in R/R FL after two or more lines of prior systemic therapy, but there is no consensus on its optimal timing in the disease course of FL, and there are no data in second-line (2L) treatment of patients with high-risk features. Lisocabtagene maraleucel (liso-cel) is an autologous, CD19-directed, 4-1BB CAR T cell product. The phase 2 TRANSCEND FL study evaluated liso-cel in patients with R/R FL, including 2L patients who all had POD24 from diagnosis after treatment with anti-CD20 antibody and alkylator ≤6 months of FL diagnosis and/or met modified Groupe d'Etude des Lymphomes Folliculaires criteria. Primary/key secondary endpoints were independent review committee-assessed overall response rate (ORR)/complete response (CR) rate. At data cutoff, 130 patients had received liso-cel (median follow-up, 18.9 months). Primary/key secondary endpoints were met. In third-line or later FL (n = 101), ORR was 97% (95% confidence interval (CI): 91.6‒99.4), and CR rate was 94% (95% CI: 87.5‒97.8). In 2L FL (n = 23), ORR was 96% (95% CI: 78.1‒99.9); all responders achieved CR. Cytokine release syndrome occurred in 58% of patients (grade ≥3, 1%); neurological events occurred in 15% of patients (grade ≥3, 2%). Liso-cel demonstrated efficacy and safety in patients with R/R FL, including high-risk 2L FL. ClinicalTrials.gov identifier: NCT04245839 .

Moving T-Cell Therapies into the Standard of Care for Patients with Relapsed or Refractory Follicular Lymphoma: A Review.

Patients with follicular lymphoma, an indolent form of non-Hodgkin lymphoma, typically experience multiple relapses over their disease course. Periods of remission become progressively shorter with worse clinical outcomes after each subsequent line of therapy. Currently, no clear standard of care/preferred treatment approach exists for patients with relapsed or refractory follicular lymphoma. As novel agents continue to emerge for treatment in the third-line setting, guidance is needed for selecting the most appropriate therapy for each patient. Several classes of targeted therapeutic agents, including monoclonal antibodies, phosphoinositide 3-kinase inhibitors, enhancer of zeste homolog 2 inhibitors, chimeric antigen receptor (CAR) T-cell therapies, and bispecific antibodies, have been approved by regulatory authorities based on clinical benefit in patients with relapsed or refractory follicular lymphoma. Additionally, antibody-drug conjugates and other immunocellular therapies are being evaluated in this setting. Effective integration of CAR-T cell therapy into the treatment paradigm after two or more prior therapies requires appropriate patient selection based on transformation status following a rebiopsy; a risk evaluation based on age, fitness, and remission length; and eligibility for CAR-T cell therapy. Consideration of important logistical factors (e.g., proximity to the treatment center and caregiver support during key periods of CAR-T cell therapy) is also critical. Overall, an individualized treatment plan that considers patient-related factors (e.g., age, disease status, tumor burden, comorbidities) and prior treatment types is recommended for patients with relapsed or refractory follicular lymphoma. Future analyses of real-world data and a better understanding of mechanisms of relapse are needed to further refine patient selection and identify optimal sequencing of therapies in this setting.

Immunogenicity of COVID-19 vaccines in patients with follicular lymphoma receiving frontline chemoimmunotherapy.

Immune responses to primary COVID-19 vaccination were investigated in 58 patients with follicular lymphoma (FL) as part of the PETReA trial of frontline therapy (EudraCT 2016-004010-10). COVID-19 vaccines (BNT162b2 or ChAdOx1) were administered before, during or after cytoreductive treatment comprising rituximab (depletes B cells) and either bendamustine (depletes CD4+ T cells) or cyclophosphamide-based chemotherapy. Blood samples obtained after vaccine doses 1 and 2 (V1, V2) were analysed for antibodies and T cells reactive to the SARS-CoV-2 spike protein using the Abbott Architect and interferon-gamma ELISpot assays respectively. Compared to 149 healthy controls, patients with FL exhibited lower antibody but preserved T-cell responses. Within the FL cohort, multivariable analysis identified low pre-treatment serum IgA levels and V2 administration during induction or maintenance treatment as independent determinants of lower antibody and higher T-cell responses, and bendamustine and high/intermediate FLIPI-2 score as additional determinants of a lower antibody response. Several clinical scenarios were identified where dichotomous immune responses were estimated with >95% confidence based on combinations of predictive variables. In conclusion, the immunogenicity of COVID-19 vaccines in FL patients is influenced by multiple disease- and treatment-related factors, among which B-cell depletion showed differential effects on antibody and T-cell responses.

Local radiotherapy and measurable residual disease-driven immunotherapy in patients with early-stage follicular lymphoma (FIL MIRO): final results of a prospective, multicentre, phase 2 trial.

BACKGROUND: The mainstay of treatment for early-stage follicular lymphoma is local radiotherapy, with a possible role for anti-CD20 monoclonal antibody (mAb). We aimed to evaluate the effect of these treatments using a measurable residual disease (MRD)-driven approach. METHODS: This prospective, multicentre, phase 2 trial was conducted at 27 centres of the Fondazione Italiana Linfomi (FIL) in Italy. Eligible participants were adults (≥18 years) with newly diagnosed, histologically confirmed follicular lymphoma (stage I or II; grade I-IIIa). Patients were initially treated with 24 Gy involved-field radiotherapy over 12 days; those who were MRD-positive after radiotherapy or during follow-up received eight intravenous doses (1000 mg per dose; one dose per week) of the anti-CD20 mAb ofatumumab. The primary endpoint was the proportion of patients who were MRD-positive after involved-field radiotherapy and became MRD-negative after ofatumumab treatment. Patients were included in the primary endpoint analysis population if they were positive for BCL2::IGH rearrangement at enrolment in peripheral blood or bone marrow samples. MRD positivity was defined as the persistence of BCL2::IGH rearrangement in peripheral blood or bone marrow, assessed centrally by laboratories of the FIL MRD Network. The trial was registered with EudraCT, 2012-001676-11. FINDINGS: Between May 2, 2015, and June 1, 2018, we enrolled 110 participants, of whom 106 (96%) were eligible and received involved-field radiotherapy. Of these, 105 (99%) were White, one (1%) was Black, 50 (47%) were male, and 56 (53%) were female. Of 105 participants in whom BCL2::IGH status was evaluable, 32 (30%) had a detectable BCL2::IGH rearrangement at baseline. After radiotherapy, 12 (40%) of 30 patients reached MRD-negative status, which was long-lasting (at least 36 or 42 months) in three (25%). In those who were MRD-positive after radiotherapy, ofatumumab induced MRD-negativity in 23 (92%; 95% CI 74-99) of 25 evaluable patients. After a median follow-up of 46·1 months (IQR 42·8-50·8), 14 (61%) of these 23 patients remain in complete response and are MRD-negative. The most common grade 3-4 adverse events were infusion-related reactions, observed in four patients. INTERPRETATION: Local radiotherapy is frequently not associated with the eradication of follicular lymphoma. An MRD-driven, anti-CD20 monoclonal antibody consolidation enables molecular remission to be reached in almost all patients and is associated with a reduced incidence of relapse over time. A clinical advantage of an MRD-driven consolidation is therefore suggested. FUNDING: AIRC Foundation for Cancer Research in Italy, Novartis International, and GlaxoSmithKline.

Time to optimize vaccination strategies in blood cancer patients.

Immune response to vaccinations is dampened in patients with indolent lymphomas due to disease and treatment-related factors. The study by Lim et al. demonstrated impaired humoral response but intact cellular response to the SARS-CoV2 vaccine in patients with follicular lymphoma receiving front-line therapy. The results highlight the importance of several factors in predicting immune response to vaccination and provide estimates of immune response for different clinical scenarios and treatment points. Commentary on: Lim et al. Immunogenicity of COVID-19 vaccines in patients with follicular lymphoma receiving frontline chemoimmunotherapy. Br J Haematol 2024;205:440-451.

Effectiveness of dose-intensified salvage regimens versus standard-dose chemotherapy for progression-free survival in early progressed follicular lymphoma before autologous stem cell transplantation: a systematic review protocol.

OBJECTIVE: This review will evaluate the effectiveness of dose-intensified versus standard-dose salvage regimens on progression-free survival in early progressed follicular lymphoma before high-dose chemotherapy and autologous stem cell transplantation. INTRODUCTION: Despite the substantial advances in the management of follicular lymphoma, approximately 20% of patients experience progression of the disease within 2 years of induction therapy. These patients have worse outcomes, and autologous stem cell transplantation has been shown to improve outcomes in this context. Little is known about the optimal salvage regimen. INCLUSION CRITERIA: Studies must include patients ≥18 years old with early progressed follicular lymphoma who were submitted to autologous stem cell transplantation in subsequent remission. Clinical trials and observational studies will be included. METHODS: The search strategy will be carried out in MEDLINE (PubMed), Embase (Periódicos CAPES), Scopus, Web of Science, LiLACS, and the Cochrane Library. No date or language restrictions will be imposed. The recommended JBI approach to critical appraisal, study selection, data extraction, and data synthesis will be used. Studies should score at least 50% in accordance with the critical appraisal tool. Data will be pooled whenever possible using the random effects model. Heterogeneity will be assessed using the standard χ 2 and I2 tests. A funnel plot will be generated to assess publication bias if there are 10 or more studies included in the meta-analysis. The GRADE approach will be used to rate certainty of evidence. REVIEW REGISTRATION: PROSPERO CRD42022373345.

Translational insights into the genetics and immunobiology of relapsed/refractory follicular lymphoma.

Although follicular lymphoma (FL) is traditionally classified as an indolent subtype of B cell non-Hodgkin lymphoma, clinical trajectories are often diverse based on unique disease biology, and many patients will eventually experience relapse of their disease. Furthermore, progression of disease within 24 months is associated with increased mortality rates for FL. In the last five years, we have witnessed an upsurge in the commercial availability of targeted therapies for relapsed/refractory (R/R) FL, including chimeric antigen receptor-T (CAR-T) products, bispecific T cell engagers (BiTEs), epigenetic modifier therapies, and next-generation Bruton tyrosine kinase (BTK) inhibitors. Furthermore, clinical trial options have increased tremendously and now include combinatorial strategies that exert synergy against malignant germinal center B cells. Here, we provide a 2024 update of novel therapeutic agents whose development has been informed by recent advances in the genetics and immunobiology of R/R FL. Specifically, we emphasize high-value targeted therapeutics, including anti-CD3 x anti-CD20 BiTEs and adoptive T cell therapies. We discuss prospects on selection and sequencing of BiTEs and CAR-T therapies for patients with R/R FL. We underscore the principles of FL pathobiology that are paving way for future drug discovery and shed insight into therapeutic targeting within nodal basins based on our increasing understanding of the FL microenvironment. Finally, we summarize how a greater knowledge of FL immunobiology can inform risk stratification and therapy selection on a personalized basis for R/R FL in 2025.