Paul J. Bröckelmann

The emerging role of immune checkpoint inhibition in malignant lymphoma

To evade elimination by the host immune system, tumor cells commonly exploit physiological immune checkpoint pathways, restraining efficient anti-tumor immune cell function. Growing understanding of the complex dialog between tumor cells and their microenvironment contributed to the development of immune checkpoint inhibitors. This innovative strategy has demonstrated paradigm-shifting clinical activity in various malignancies. Antibodies targeting programmed death 1 and cytotoxic T-lymphocyte-associated protein-4 are also being investigated in lymphoid malignancies with varying levels of activity and a favorable toxicity profile. To date, evaluated only in the setting of relapsed or refractory disease, anti-programmed death 1 antibodies such as nivolumab and pembrolizumab show encouraging response rates particularly in classical Hodgkin lymphoma but also in follicular lymphoma and diffuse-large B-cell lymphoma. As the first immune checkpoint inhibitor in lymphoma, nivolumab was approved for the treatment of relapsed or refractory classical Hodgkin lymphoma by the Food and Drug Administration in May 2016. In this review, we assess the role of the pathways involved and potential rationale of checkpoint inhibition in various lymphoid malignancies. In addition to data from current clinical trials, immune-related side effects, potential limitations and future perspectives including promising combinatory approaches with immune checkpoint inhibition are discussed.

Current and future immunotherapeutic approaches in Hodgkin lymphoma

Abstract Hodgkin lymphoma (HL) has become a highly curable malignancy even in advanced stages when treated adequately. However, relapsed or refractory disease and treatment-related toxicity constitute a significant clinical challenge. Innovative approaches are thus needed to improve treatment of these mainly young patients. In HL lesions, very few malignant Hodgkin and Reed-Sternberg (HRS) cells are embedded in an immunosuppressive microenvironment of reactive cells. Novel approaches such as bispecific antibodies, antibody-drug conjugates, immune-checkpoint inhibitors or adoptive cellular therapies are currently being investigated with promising results in relapsed or refractory patients. Encouraging response rates and a favorable toxicity profile have recently been reported in early phase clinical trials with antibodies blocking the programed-death receptor 1 (PD1). This review will summarize the current clinical knowledge on mechanism, safety and efficacy of the different agents and discuss potential future strategies, which are partly already investigated within clinical trials.

Long-Term Follow-Up of Contemporary Treatment in Early-Stage Hodgkin Lymphoma: Updated Analyses of the German Hodgkin Study Group HD7, HD8, HD10, and HD11 Trials

Purpose Combined-modality treatment is widely considered the standard of care in early-stage Hodgkin lymphoma (HL), and treatment intensity has been reduced over the last years. Long-term follow-up is important to judge both efficacy and safety of the different therapies used. Patients and Methods We analyzed updated follow-up data on 4,276 patients treated within the German Hodgkin Study Group trials HD7 and HD10 for early-stage favorable HL and HD8 and HD11 for early-stage unfavorable HL between 1993 and 2003. Results In HD7 (N = 627; median follow-up, 120 months), combined-modality treatment was superior to extended-field radiotherapy (RT), with 15-year progression-free survival (PFS) of 73% versus 52% (hazard ratio [HR], 0.5; 95% CI, 0.3 to 0.6; P < .001), without differences in overall survival (OS). In HD10 (N = 1,190; median follow-up, 98 months), noninferiority of two cycles of doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) plus 20 Gy involved-field (IF)-RT to more intensive four cycles of ABVD plus 30 Gy IF-RT was confirmed with 10-year PFS of 87% each (HR, 1.0; 95%, 0.6 to 1.5) and OS of 94% each (HR, 0.9; 95% CI, 0.5 to 1.6), respectively. In both trials, no differences in second neoplasias were observed. In HD8 (N = 1,064; median follow-up, 153 months), noninferiority of involved-field RT to extended-field RT regarding PFS was confirmed (HR, 1.0; 95% CI, 0.8 to 1.2). In HD11 (N = 1,395; median follow-up, 106 months), superiority of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone at baseline over ABVD was not observed. After BEACOPPbaseline, 20 Gy IF-RT was noninferior to 30 Gy (10-year PFS, 84% v 84%; HR, 1.0; 95% CI, 0.7 to 1.5). In contrast, PFS was inferior in ABVD-treated patients receiving 20 Gy instead of 30 Gy IF-RT (10-year PFS, 76% v 84%; HR, 1.5; 95% CI, 1.0 to 2.1). No differences in OS or second neoplasias were observed in in both trials. Conclusion Long-term follow-up data of the four randomized trials largely support the current risk-adapted therapeutic strategies in early-stage HL. Nevertheless, continued follow-up is necessary to assess the long-term safety of currently applied therapeutic strategies.

Risk factors and a prognostic score for survival after autologous stem-cell transplantation for relapsed or refractory Hodgkin lymphoma

Background Novel agents are changing the treatment of relapsed or refractory Hodgkin lymphoma (HL). Nevertheless, high-dose chemotherapy and autologous stem-cell transplantation (ASCT) are considered standard of care in eligible patients. To identify patients who could benefit most from novel therapeutic approaches, we investigated a comprehensive set of risk factors (RFs) for survival after ASCT. Methods In this multinational prognostic multivariable modeling study, 23 potential RFs were retrospectively evaluated in HL patients from nine prospective trials with multivariable Cox proportional hazards regression analyses (part I). The resulting prognostic score was then validated in an independent clinical sample (part II). Results In part I, we identified 656 patients treated for relapsed/refractory HL between 1993 and 2013 with a median follow-up of 60 months after ASCT. The majority of potential RFs had significant impact on progression-free survival (PFS) with hazard ratios (HR) ranging from 1.39 to 2.22. The multivariable analysis identified stage IV disease, time to relapse ≤3 months, ECOG performance status ≥1, bulk ≥5 cm and inadequate response to salvage chemotherapy [<partial remission by computed tomography (CT)] as significant and non-redundant RFs for PFS. A risk score composed of these equally weighed RFs was significantly prognostic for PFS (HR = 1.67 for each additional RF; P < 0.0001). Validation in an independent sample of 389 patients treated in different clinical settings with evaluation of response to salvage therapy by functional imaging instead of CT confirmed the excellent discrimination of risk groups and significant prognostication of PFS and overall survival (OS) after ASCT (HR = 1.70 and HR = 1.63, respectively; P < 0.0001). Conclusions Based on this large study (n = 1045), precise and valid risk prognostication in HL patients undergoing ASCT can be achieved with five easily available clinical RFs. The proposed prognostic score hence allows reliable stratification of patients for innovative therapeutic approaches in clinical practice and future trials. Registered trials GHSG HD10 NCT00265018, HD11 NCT00264953, HD12 NCT00265031, HD13 ISRCTN63474366, HD14 ISRCTN04761296, HD15 ISRCTN32443041 and HDR2 NCT00025636.

Ofatumumab in relapsed nodular lymphocyte-predominant Hodgkin lymphoma: results of a phase II study from the German Hodgkin study group

Ofatumumab in relapsed nodular lymphocyte-predominant Hodgkin lymphoma: results of a phase II study from the German Hodgkin study group

Late Relapse of Classical Hodgkin Lymphoma: An Analysis of the German Hodgkin Study Group HD7 to HD12 Trials

Purpose Clinical characteristics, therapeutic approaches, and prognosis of late relapse (LR) in patients with classic Hodgkin lymphoma (cHL) are poorly understood. We performed a comprehensive analysis of LR of Hodgkin lymphoma (LR-HL). Methods To estimate the incidence of LR-HL, we retrospectively analyzed 6,840 patients with cHL included in the German Hodgkin Study Group trials HD7 to HD12. Patients who experienced a relapse > 5 years into remission were compared with patients in continued remission for > 5 years and with those who experienced a relapse ≤ 5 years after first diagnosis. Results With a median observation time of 10.3 years, 141 incidences of LR-HL were observed. Cumulative incidences at 10, 15, and 20 years rose linearly and were 2.5%, 4.3%, and 6.9%, respectively. The standardized incidence ratio for HL with respect to age- and sex-matched German reference data was 84.5 (95% CI, 71.2 to 99.7). LR-HL was more frequently observed in patients with early-stage favorable than unfavorable or advanced stage at first diagnosis (15-year cumulative incidence, 5.3% v 3.9% and 3.9%, respectively; P = .01). Overall survival from first diagnosis was worse after LR compared with nonrelapse survivors (10-year estimate, 95.8% v 86.1%; hazard ratio, 2.5; 95% CI, 1.7 to 3.5; P < .001). In patients with LR-HL, survival was better compared with 466 patients with earlier relapse (hazard ratio, 0.6; 95% CI, 0.4 to 0.9, P = .01). Forty-four percent and 49% of patients with LR-HL and earlier relapse, respectively, received stem cell transplantations. Conclusion Apart from treatment-associated adverse effects, survivors after initially successful therapy for cHL are at an 85-fold risk for recurrence of disease compared with the general German population. After risk-adapted treatment strategies, especially in early-stage favorable HL, regular clinical follow-up is recommended for timely detection of LR-HL. With adequate treatment, prognosis of LR-HL is better compared with early relapses.

Checkpoint Inhibition in Hodgkin Lymphoma - a Review

Physiological immune checkpoint pathways are important to regulate self-tolerance, limit immune reactions, and moderate autoimmunity. Various cancers are commonly exploiting these mechanisms to evade the host immune system by restraining a durable, efficient anti-tumor immune response. Immune checkpoints include, but are not limited to, the programmed death 1 (PD1) and the cytotoxic T-lymphocyte-associated protein-4 (CTLA4) axis, which are both druggable by monoclonal antibodies referred to as checkpoint inhibitors (CIs). To date, the anti-PD1 antibodies nivolumab and pembrolizumab are approved for relapsed or refractory classical Hodgkin lymphoma (cHL) due to high response rates with a favorable yet distinct safety profile, and other agents are under investigation. This review summarizes the available preclinical and clinical data including the toxicity and efficacy of different CIs in cHL. It also provides future perspectives based on ongoing clinical trials, potentially synergistic combinatory approaches, and their fit in the therapeutic landscape in cHL.

Impact of centralized diagnostic review on quality of initial staging in Hodgkin lymphoma: experience of the German Hodgkin Study Group.

Accurate clinical staging is crucial for adequate risk‐adapted treatment in Hodgkin lymphoma (HL) to prevent patients from under‐ or over‐treatment. Within the latest German Hodgkin Study Group trial generation, diagnostic findings such as histopathology, computerized tomography imaging and clinical risk factors were re‐evaluated by expert panels. Here, we retrospectively analysed 5965 patients and identified 399 in who major discordant findings changed their first‐line treatment allocation. Histopathology review did not confirm the initial diagnosis of HL in 87 patients. Treatment allocation was revised in 312 of the remaining 5878 patients: 176 were assigned to a higher and 128 to a lower risk group, respectively; the correct treatment group remained unclear in 8 patients. Cases of revised treatment allocation accounted for 9·8%, 6·0%, 0·8%, and 14·8% of patients initially assigned to the HD13, HD14, HD15 trials and stage IA lymphocyte‐predominant HL project, respectively. Most revisions were due to wrong application of clinical stage (20·5% of 312 patients with revised treatment group), histological subtype (9·0%) or the risk factors ≥3 involved areas (46·8%) or large mediastinal mass (9·3%). In conclusion, centralized review by experienced experts changed risk‐adapted first‐line treatment in a relevant proportion of HL patients. Quality control measures clearly improve the accuracy of treatment and should be implemented in clinical practice.

Leucocyte and eosinophil counts predict progression‐free survival in relapsed or refractory classical Hodgkin Lymphoma patients treated with PD1 inhibition

imab can be safely administered without the need for any pre-medication. In our data, the apparent rate of reactions was higher for those subcutaneous doses where premedication was given than for those given without; although this may be explained by increased patient surveillance as the ‘covered’ doses were given in the context of clinical trials. It has already been shown that subcutaneous administration of Rituximab improves cost effectiveness and patient experience when compared with the intravenous route (Rule et al, 2014). Administering subcutaneous Rituximab without premedication further reduces administration time, improving efficiency and patient experience; and means that patients are not exposed to the potential sedative effects of antihistamines. This reduces the burden on patients and families as patients can drive themselves to appointments, and return to work immediately after treatment. The extremely good side effect profile that we have observed means that the drug could be safely given closer to home and even within the home environment. Furthermore, given that there is growing evidence that giving Alemtuzumab subcutaneously as a first dose is associated with a favourable side effect profile compared to the intravenous route (Lundin et al, 2002; Patel et al, 2016), we suggest that the same may be true with Rituximab, and it may be possible to give the first dose subcutaneously rather than intravenously, further improving safety and efficiency.

Balancing risk and benefit in early-stage classical Hodgkin lymphoma.

With defined chemotherapy and radiotherapy (RT) and risk-adapted treatment, early-stage classical Hodgkin lymphoma (HL) has become curable in a majority of patients. Hence, a major current goal is to reduce treatment-related toxicity while maintaining long-term disease control. Patients with early-stage favorable disease (ie, limited stage without risk factors [RFs]) are frequently treated with 2 cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (2×ABVD) followed by 20-Gy involved-field or involved-site RT (IF/ISRT). In patients with early-stage unfavorable disease (ie, limited stage with RFs), 4 cycles of chemotherapy are usually consolidated with 30-Gy IF/ISRT. Compared with 4×ABVD, 2 cycles of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (2×BEACOPPescalated) followed by 2×ABVD improved 5-year progression-free survival (PFS), with similar 5-year overall survival. Recently, treatment strategies based on [18F]fluorodeoxyglucose positron emission tomography (PET) response were evaluated. In early-stage unfavorable HL, a majority of patients achieved a negative interim PET after 2×ABVD and an excellent outcome after 4×ABVD, whereas in those with a positive interim PET, 2×BEACOPPescalated improved 5-year PFS. Furthermore, a PET-guided RT approach was evaluated to decrease long-term toxicity. Although both the RAPID and H10 trials reported poorer disease control without RT, PET-guided omission of RT can constitute a valid therapeutic option in patients with an increased risk of RT-associated toxicity (eg, because of sex, age, or disease localization). Implementation of drugs such as the anti-CD30 antibody-drug conjugate brentuximab vedotin or the anti-programmed death 1 antibodies nivolumab or pembrolizumab might allow further reduction of overall mortality and improve quality of life in affected patients.