Durable remissions in a pivotal phase 2 study of brentuximab vedotin in relapsed or refractory Hodgkin lymphoma. Blood. 2015;125:1236-1243. [PMID: 25533035 DOI: 10.1182/blood-2014-08-595801]

Novel agents positively impact chemotherapy and transplantation in Hodgkin lymphoma

INTRODUCTION

Majority of patients with Hodgkin lymphoma (HL) can be successfully cured with frontline conventional therapeutics. Approximately 50-60% of those whose disease recur or is refractory to conventional treatment, can be cured with salvage therapies followed by autologous hematopoietic cell transplantation (AHCT). Conventional treatments, however, may cause significant long-term toxicities. Areas covered: This article reviews the treatment advances in HL with the incorporation of novel and targeted agents that are aimed to improve cure rates while reducing toxicities. Expert opinion: Brentuximab vedotin (BV) and checkpoint inhibitors have demonstrated clear clinical benefit in HL. Majority of patients receive BV before or directly after AHCT as part of salvage or maintenance regimens. In patients who relapse after AHCT, checkpoint inhibitors are the treatment of choice, either as a stand-alone therapy or more commonly as a bridge to a potentially curative allogeneic hematopoietic cell transplantation (alloHCT). A multitude of other targeted agents and combinations, as well as cellular and immunotherapeutic in HL, are under investigation.

Should all patients with HL who relapse after ASCT be considered for allogeneic SCT? A consult, yes; a transplant, not necessarily

This article has a companion Point by Peggs.

Cost-effectiveness of brentuximab vedotin plus chemotherapy as frontline treatment of stage III or IV classical Hodgkin lymphoma

OBJECTIVE

The ECHELON-1 trial demonstrated efficacy and safety of brentuximab vedotin plus doxorubicin, vinblastine, and dacarbazine (A + AVD) vs doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) as frontline therapy for stage III/IV classical Hodgkin lymphoma. This analysis evaluated the cost-effectiveness of A + AVD from a US healthcare payer perspective.

METHODS

The incremental cost-effectiveness ratio (ICER), defined as the incremental costs per quality-adjusted life year (QALY) gained, was estimated using a non-homogenous semi-Markov cohort model with health states defined on progression following frontline treatment, and for those with progression, receipt of autologous stem-cell transplant (ASCT), and progression after ASCT. Patients undergoing ASCT were classified as refractory or relapsed based on timing of progression. Probabilities of progression/death with frontline therapy were based on parametric survival distributions fit to data on modified progression-free survival (mPFS) from ECHELON-1. Duration of frontline treatment and incidence of adverse events were from ECHELON-1. Utility values for patients in the frontline mPFS state were based on EQ-5D data from ECHELON-1. Other inputs were from published sources. A lifetime time horizon was used. Costs and QALYs were discounted at 3%. Analyses were conducted alternately using data on mPFS for the overall and North American populations of ECHELON-1.

RESULTS

The ICER for A + AVD vs ABVD was $172,074/QALY gained in the analysis using data on mPFS for the overall population and $69,442/QALY gained in the analysis using data on mPFS for the North American population of ECHELON-1. The ICER is sensitive to estimated costs of ASCT and frontline failure.

CONCLUSION

The ICER for A + AVD vs ABVD based on ECHELON-1 is within the range of threshold values for cost-effectiveness in the US. A + AVD is, therefore, likely to be a cost-effective frontline therapy for patients with stage III/IV classical Hodgkin lymphoma from a US healthcare payer perspective.

Bone Marrow Mast Cell Antibody-Targetable Cell Surface Protein Expression Profiles in Systemic Mastocytosis

Despite recent therapeutic advances, systemic mastocytosis (SM) remains an incurable disease due to limited complete remission (CR) rates even after novel therapies. To date, no study has evaluated the expression on SM bone marrow mast cells (BMMC) of large panel of cell surface suitable for antibody-targeted therapy. In this study, we analyzed the expression profile of six cell-surface proteins for which antibody-based therapies are available, on BMMC from 166 SM patients vs. 40 controls. Overall, variable patterns of expression for the markers evaluated were observed among SM BMMC. Thus, CD22, CD30, and CD123, while expressed on BMMC from patients within every subtype of SM, showed highly variable patterns with a significant fraction of negative cases among advanced SM (aggressive SM (ASM), ASM with an associated clonal non-MC lineage disease (ASM-AHN) and MC leukemia (MCL)), 36%, 46%, and 39%, respectively. In turn, CD25 and FcεRI were found to be expressed in most cases (89% and 92%) in virtually all BMMC (median: 92% and 95%) from both indolent and advanced SM, but with lower/absent levels in a significant fraction of MC leukemia (MCL) and both in MCL and well-differentiated SM (WDSM) patients, respectively. In contrast, CD33 was the only marker expressed on all BMMC from every SM patient. Thus, CD33 emerges as the best potentially targetable cell-surface membrane marker in SM, particularly in advanced SM.

Cost-Effectiveness Analysis of Brentuximab Vedotin With Chemotherapy in Newly Diagnosed Stage III and IV Hodgkin Lymphoma

PURPOSE

In a recent randomized, open-label trial (ECHELON-1), brentuximab vedotin (BV) combined with doxorubicin, vinblastine, and dacarbazine (AVD+BV) decreased the risk of progression in adults diagnosed with stage III or IV Hodgkin lymphoma (HL) compared with standard bleomycin-containing chemotherapy (doxorubicin, bleomycin, vinblastine, and dacarbazine [ABVD]). However, the cost effectiveness of incorporating BV (US$6,970 per 50-mg vial) into the first-line setting is unknown.

PATIENTS AND METHODS

We constructed a Markov decision-analytic model to measure the costs and clinical outcomes for AVD+BV compared with ABVD as first-line therapy in a cohort of patients with stage III or IV HL. Transition probabilities were estimated from ECHELON-1 by fitting parametric survival distributions. Lifetime direct health care costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs) were calculated for AVD+BV compared with ABVD from a US payer perspective. Our model was also used to estimate BV price reductions that would achieve more favorable cost effectiveness under indication-specific pricing.

RESULTS

AVD+BV was associated with an improvement of 0.56 QALYs compared with treatment with standard ABVD. However, incorporating BV into first-line therapy led to significantly higher lifetime health care costs ($361,137 v $184,291), causing the ICER for AVD+BV to be $317,254 per QALY. If indication-specific pricing were implemented, acquisition costs for BV used in the first-line setting would need to be reduced by 56% to 73% for ICERs of $150,000 to $100,000 per QALY, respectively.

CONCLUSION

Substituting BV for bleomycin during first-line therapy for stage III or IV HL is unlikely to be cost effective under current drug pricing. Should indication-specific pricing be implemented, significant price reductions for BV used in the first-line setting would be needed to reduce ICERs to more widely acceptable values.

Treatment-Resistant Hodgkin Lymphoma: Defining the Role of Autologous Transplantation

Autologous hematopoietic stem cell transplant (AHCT) remains the current standard of care for patients with relapsed or refractory Hodgkin lymphoma (HL) after frontline chemotherapy. However, treatment paradigms for HL are rapidly changing with positron emission tomography-adapted therapy, as well as the incorporation of brentuximab vedotin and checkpoint inhibitors into frontline, salvage, and maintenance therapy for HL. Patients who relapse or are refractory to these novel agents are likely to have different responses and outcomes with AHCT than the 3-year event-free survivals of 50% historically reported with AHCT for patients failing conventional combination chemotherapy. This article reviews the current data on the efficacy of AHCT, pretransplant prognostic markers, pretransplant salvage regimens, peritransplant radiation therapy, and posttransplant maintenance therapy in classic HL. Future research should reexamine the efficacy, timing, risk factors, pretransplant salvage regimens, and maintenance approaches posttransplant in the era of brentuximab vedotin and checkpoint inhibitors for HL.

Treatment patterns, health care resource utilization, and costs in patients with relapsed/refractory Hodgkin lymphoma treated with brentuximab vedotin

Data are limited on the real-world utilization and costs of brentuximab vedotin (BV) among patients with relapsed/refractory Hodgkin lymphoma (rrHL) in the United States. A total of 219 BV patients identified from the Truven MarketScan^® databases were followed up for a median of 2.9 years before and 1.0 year after initiation of BV. Of these patients, 109 (50.6%) received systemic therapy after BV (post-BV ST). Median duration of treatment was short for BV (2.1 months) and post-BV ST treatment (1.3 months); time to next treatment was 6.2 and 9.1 months, respectively. Average total US dollar 2014 costs/person for BV and post-BV ST line of therapy were $167,152 and $132,115, respectively; mean per-patient-per-month costs for BV and post-BV ST were $30,434 and $29,138, respectively. Findings underscore the unmet medical need and substantial economic burden in BV-treated patients with rrHL.

Update on the role of brentuximab vedotin in classical Hodgkin lymphoma

Brentuximab vedotin (BV) is an effective and well-tolerated treatment for patients with classical Hodgkin lymphoma (HL). It was initially approved by the US FDA for the treatment of HL after failure of autologous hematopoietic stem cell transplant (autoHSCT) or after failure of at least two prior lines of multiagent chemotherapy in patients who are not transplant candidates, and then subsequently, as consolidation therapy after autoHSCT in patients who are at high risk for relapse. However, the role of BV in the treatment of HL is evolving. BV has shown promising efficacy as a salvage treatment in the second-line setting prior to autoHSCT. Most recently, the ECHELON-1 trial demonstrated that BV combined with AVD for the treatment of newly diagnosed advanced stage HL improved modified progression-free survival (mPFS) compared with standard ABVD. Based on these results, the US FDA has approved BV as part of the initial treatment of advanced stage HL. With the approval of BV as front-line therapy, depending on how widely the use of BV plus AVD is adopted, the role of BV in the treatment of patients with relapsed or refractory (rel/ref) HL may need to be redefined. BV retreatment can be effective, and studies of rational BV-based combination regimens may help to improve response rates and overcome BV resistance. Furthermore, BV has been demonstrated to be effective in the initial treatment of elderly or unfit patients, and ongoing studies are evaluating the addition of BV to initial chemotherapy in patients with early stage HL.

Determining the sequence of novel therapies in the treatment of relapsed Hodgkin's lymphoma

INTRODUCTION

Hodgkin's lymphoma (HL) accounts for about 10% of all lymphomas in the U.S.A. Exceptional progress has been made in the treatment of HL with complete response (CR) rates up to 94% in limited stage and 88% in advanced stage disease with regimens such as adriamycin, bleomycin, vinblastine, and dacarbazine in the frontline setting. Nevertheless, up to 10% of patients with limited stage disease and 20-30% of those with advanced stage HL relapse. In the last decade, newer agents such as brentuximab vedotin (BV) and checkpoint inhibitors have been approved by the FDA for treatment of patients with relapsed or refractory HL. As these newer agents are increasingly incorporated in both the frontline and relapsed settings, their optimal sequence becomes challenging for clinicians. Areas covered: This review will discuss the evidence behind the approval of BV and checkpoint inhibitors in HL and the appropriate sequence for using them in relapsed HL. Expert commentary: The appropriate sequence of BV and/or checkpoint inhibitors in the relapsed setting depends on the regimen used in the frontline setting.

Building upon the success of CART19: chimeric antigen receptor T cells for hematologic malignancies

Chimeric antigen receptor T cell (CART) therapy has dramatically changed the therapeutic prospects for B cell malignancies. Over the last decade CD19-redirected CART have demonstrated the ability to induce deep, long-lasting remissions and possibly cure patients with relapsing B cell neoplasms. Such impressive results with CART19 fostered efforts to expand this technology to other incurable malignancies that naturally do not express CD19, such as acute myeloid leukemia (AML), Hodgkin lymphoma (HL) and multiple myeloma (MM). However, to reach this goal, several hurdles have to be overcome, in particular: (i) the apparent lack of suitable targets as effective as CD19; (ii) the immunosuppressive tumor microenvironment; (iii) intra-tumoral heterogeneity and antigen-negative relapses. Therefore, new strategies that allow safer and more potent CART platforms are under development and may provide grounds for new exciting breakthroughs in the field.

18F-FDG PET/CT for response assessment in Hodgkin lymphoma undergoing immunotherapy with checkpoint inhibitors

Our aim was to evaluate Hodgkin Lymphoma (HL) response to checkpoint inhibitors with ¹⁸F-FDG PET/CT. Forty three refractory or relapsed HL patients were investigated before immunotherapy, 8 weeks and 17 weeks after administration of either nivolumab or pembrolizumab. The median follow-up was 19 months. Best clinical response was complete response (CR) in 26 patients, partial response (PR) in 5 patients, stable disease (SD) in 8 patients, and progression disease (PD) in 4 patients. At the early assessment, Deauville Score (DS) resulted significantly different in responder group compared to nonresponders. SUVmax was significantly lower in responders, while there was no relevant modification in the tumor burden. At interim evaluation, DS well differentiated responder group. A significant decrease in glucose metabolism and tumor burden parameters was observed in responder patients, who presented with a longer progression-free survival then nonresponders. ¹⁸F-FDG PET/CT provides a reliable indication of treatment response under checkpoints inhibitors, even at an early assessment.

Targeting Immune System Alterations in Hodgkin Lymphoma

PURPOSE OF REVIEW

This review discusses novel immunotherapeutic approaches to treat Hodgkin lymphoma (HL), specifically PD-1 inhibitors and cellular immunotherapy.

RECENT FINDINGS

PD-1 inhibitors have shown promising results in the treatment of relapsed or refractory HL, leading to FDA approval of nivolumab and pembrolizumab, although complete remissions are rare. Chimeric antigen receptor T cells directed against CD30 have been investigated with preliminary clinical trials showing minimal toxicities and some responses in heavily pre-treated patients with HL. HL is unique as it consists of a small percentage of malignant cells (Hodgkin Reed Sternberg cells) surrounded by an inflammatory microenvironment which promotes tumor growth and suppresses immune responses, making it an ideal target for immunotherapeutic approaches, such as PD-1 inhibitors and cellular immunotherapy. Current research is focused on overcoming barriers to efficacy via rational combinations that overcome resistance to therapy.

Treatment of classical Hodgkin lymphoma in the era of brentuximab vedotin and immune checkpoint inhibitors

The majority of Hodgkin lymphoma patients are now cured with conventional first-line therapy; however, 10-15% of early-stage disease and less than 30% of advanced-stage patients are refractory(rare) or relapsed. Salvage second-line therapy combined with high-dose therapy and autologous stem-cell transplantation can cure 40-50% of patients. Recently novel agents (Brentuximab Vedotin and Immune Checkpoint inhibitors) have demonstrated evidence of therapeutic activity and are potential bridge to an allogeneic stem-cell transplantation. The review is aimed to present not only salvage strategies; indeed, the paper contains paragraphs about therapy and new treatment options at diagnosis.

Prevention and treatment of relapse after stem cell transplantation in lymphoid malignancies

Relapse is now the major cause of treatment failure after allogeneic HSCT (alloHSCT). Many novel strategies to address this critical issue are now being developed and tested. At the 3rd International Workshop on Biology, Prevention, and Treatment of Relapse held in Hamburg, Germany in November 2016, international experts presented and discussed recent developments in the field. Some approaches may be applicable to a wide range of patients after transplant, whereas some may be very disease-specific. We present a report from the session dedicated to issues related to prevention and treatment of relapse of lymphoid malignancies after alloHSCT. This session included detailed reviews as well as forward-looking commentaries that focused on Hodgkin lymphoma, chronic lymphocytic leukemia and mantle cell lymphoma, diffuse large cell and follicular lymphoma, and multiple myeloma.

New Treatment Algorithms in Hodgkin Lymphoma: Too Much or Too Little?

Hodgkin lymphoma treatment continues to evolve as new means of assessing response to treatment, new appreciation of important risk factors, and more effective therapeutic agents become available. Treatment algorithms integrating functional imaging now provide the opportunity to modify therapy during its delivery, allowing adjustment of duration and intensity of chemotherapy and rationale identification of patients who may benefit from the addition of therapeutic irradiation. Novel agents, including the antibody drug conjugate brentuximab vedotin and checkpoint inhibitors such as nivolumab and pembrolizumab can improve the effectiveness of treatment while keeping toxicity within acceptable limits. Carefully designed clinical trials permit the identification of superior approaches in which efficacy is enhanced and toxicity minimized. Clinicians treating patients with Hodgkin lymphoma now have access to novel treatment approaches, which will require detailed assessment of each patient and careful discussion of the goals and risks of treatment at the time of planning primary treatment, again during delivery of that treatment as data indicating ongoing effectiveness become available, at the conclusion of initial intervention, and, when the need arises, at the time of recurrence of disease.

Phase 2 study of everolimus for relapsed or refractory classical Hodgkin lymphoma

Background

The current standard of care for classical Hodgkin lymphoma (HL) is multiagent chemotherapy with or without radiation. In patients who relapse or fail to respond, additional high-dose chemotherapy with autologous hematopoietic stem cell transplantation (AHSCT) can improve progression-free survival (PFS). Novel therapies are required for patients refractory to chemotherapy and AHSCT. The mammalian target of rapamycin inhibitor everolimus has shown preliminary activity in preclinical models of HL and promising efficacy in patients with relapsed or refractory HL.

Methods

This was an open-label, two-stage, phase 2 study that enrolled 57 patients aged ≥ 18 years with classic HL that had progressed after standard therapy. Patients received everolimus 10 mg daily until disease progression, intolerable toxicity, withdrawal of consent, or investigator decision. The primary endpoint was overall response rate; secondary endpoints included PFS, overall survival, time to response, duration of response, and safety.

Results

Overall response rate was 45.6% (95% confidence interval [CI] 32.4–59.3%); five patients (8.8%) experienced a complete response and 21 patients had a partial response (36.8%). Median PFS was 8.0 months (95% CI 5.1–11.0 months). Seven patients (12%) were long-term responders (≥ 12 months). The most common study drug-related adverse events were thrombocytopenia (45.6%), fatigue (31.6%), anemia (26.3%), rash (24.6%), and stomatitis (22.8%).

Conclusions

Everolimus 10 mg/day demonstrated favorable results in patients with heavily pretreated, relapsed, or refractory classical HL. These findings support the further evaluation of everolimus in this indication.

Trial registration ClinicalTrials.gov NCT01022996. Registered November 25, 2009

Brentuximab vedotin plus bendamustine: a highly active first salvage regimen for relapsed or refractory Hodgkin lymphoma

Autologous stem cell transplantation (ASCT) is standard of care for patients with Hodgkin lymphoma (HL) who have relapsed/refractory disease after frontline chemotherapy. Achievement of complete remission (CR) with pre-ASCT salvage chemotherapy predicts favorable outcomes post-ASCT. This phase 1/2 study evaluated the combination of brentuximab vedotin (BV) plus bendamustine as a first salvage regimen in relapsed/refractory HL. A total of 55 patients (28 primary refractory and 27 relapsed) were enrolled. Patients received BV (1.8 mg/kg) on day 1 and bendamustine (90 mg/m²) on days 1 and 2 of a 21-day cycle for up to 6 cycles. Patients could undergo ASCT any time after cycle 2. Following ASCT or completion of combination therapy if not proceeding to ASCT, patients could receive BV monotherapy for up to 16 cycles of total therapy. After a median of 2 cycles of combination therapy (range, 1-6), the objective response rate among 53 efficacy-evaluable patients was 92.5%, with 39 patients (73.6%) achieving CR. Forty patients underwent ASCT. Thirty-one patients (25 of whom underwent ASCT) received BV monotherapy (median, 10 cycles; range, 1-14). After a median of 20.9 months of follow-up, the estimated 2-year progression-free survival was 69.8% and 62.6% for patients who received ASCT and all patients, respectively. Thirty-one patients (56.4%) experienced infusion-related reactions (IRRs), with a majority occurring during cycle 2 of combination therapy. A protocol amendment requiring premedication reduced IRR severity. BV plus bendamustine as first salvage therapy in relapsed/refractory HL is highly active with a manageable toxicity profile. This trial was registered at www.clinicaltrials.gov as #NCT01874054.

Advances in CD30- and PD-1-targeted therapies for classical Hodgkin lymphoma

CD30 and programmed cell death protein 1 (PD-1) are two ideal therapeutic targets in classical Hodgkin lymphoma (cHL). The CD30 antibody-drug conjugate (ADC) brentuximab vedotin and the PD-1 antibodies nivolumab and pembrolizumab are highly efficacious in treating relapsed and/or refractory cHL. Ongoing studies are evaluating their efficacy in earlier lines of therapy and have demonstrated encouraging results. These agents are expected to further change the landscape of cHL management. Increased cure rates and reduced long-term toxicity from traditional chemotherapy and radiotherapy are likely with the emergence of these novel targeted therapies.

Sequential immunotherapy in a patient with primary refractory Hodgkin lymphoma and novel mutations

Primary resistant Hodgkin lymphoma is an aggressive disease with few treatment options and short survival. Neoplastic cells of classical Hodgkin lymphoma are heavily dependent on microenvironmental stimuli, regularly express PD-L1, and a relevant proportion of relapsed patients is sensitive to blocking of the PD1/PD-L1 axis. However, response duration is limited and further treatment options are unknown but urgently needed.

We report a case of a patient without relevant response to five subsequent chemotherapy regimens who immediately and dramatically responded to an anti-PD1 mab. During the following two years she responded to the anti-CTLA-4 mab ipilimumab, the Jak2 inhibitor ruxolitinib, and a combination of lenalidomide plus cyclophosphamide given in subsequent relapses. A thorough genomic analysis demonstrated seven genomic alterations with six of them not previously described in this disease (i.e. BRIP1 G212fs*62, KRAS L19F, KDM5A R1239W, MYC A59T, ARIDA1A E1683fs*15 and TP53 277Y). Three alterations were considered actionable and one of them drugable. The number of mutations increased over time and the BRIP1 mutation was found to be a germline mutation.

Treatment Options for Paediatric Anaplastic Large Cell Lymphoma (ALCL): Current Standard and beyond

Anaplastic Lymphoma Kinase (ALK)-positive Anaplastic Large Cell Lymphoma (ALCL), remains one of the most curable cancers in the paediatric setting; multi-agent chemotherapy cures approximately 65–90% of patients. Over the last two decades, major efforts have focused on improving the survival rate by intensification of combination chemotherapy regimens and employing stem cell transplantation for chemotherapy-resistant patients. More recently, several new and ‘renewed’ agents have offered the opportunity for a change in the paradigm for the management of both chemo-sensitive and chemo-resistant forms of ALCL. The development of ALK inhibitors following the identification of the EML4-ALK fusion gene in Non-Small Cell Lung Cancer (NSCLC) has opened new possibilities for ALK-positive ALCL. The uniform expression of CD30 on the cell surface of ALCL has given the opportunity for anti-CD30 antibody therapy. The re-evaluation of vinblastine, which has shown remarkable activity as a single agent even in the face of relapsed disease, has led to the consideration of a revised approach to frontline therapy. The advent of immune therapies such as checkpoint inhibition has provided another option for the treatment of ALCL. In fact, the number of potential new agents now presents a real challenge to the clinical community that must prioritise those thought to offer the most promise for the future. In this review, we will focus on the current status of paediatric ALCL therapy, explore how new and ‘renewed’ agents are re-shaping the therapeutic landscape for ALCL, and identify the strategies being employed in the next generation of clinical trials.

Phase II study of idelalisib, a selective inhibitor of PI3Kδ, for relapsed/refractory classical Hodgkin lymphoma

Background

The phosphatidylinositol-3-kinase delta (PI3Kδ) inhibitor idelalisib has been shown to block downstream intracellular signaling, reduce the production of prosurvival chemokines and induce apoptosis in classical Hodgkin lymphoma (HL) cell lines. It has also been shown to inhibit regulatory T cells and myeloid-derived suppressor cells in other tumor models. We hypothesized that inhibiting PI3Kδ would have both direct and indirect antitumor effects by directly targeting the malignant cells as well as modulating the inflammatory microenvironment. We tested this hypothesis in a phase II study.

Patients and methods

We enrolled 25 patients with relapsed/refractory HL with a median age of 42 years and who had previously received a median of five therapies including 18 (72%) with failed autologous stem cell transplant, 23 (92%) with failed brentuximab vedotin, and 11 (44%) with prior radiation therapy. Idelalisib was administered at 150 mg two times daily; an increase to 300 mg two times daily was permitted at the time of disease progression.

Results

The overall response rate to idelalisib therapy was 20% (95% confidence interval: 6.8%, 40.7%) with a median time to response of 2.0 months. Seventeen patients (68%) experienced reduction in target lesions with one complete remission and four partial remissions. The median duration of response was 8.4 months and median progression-free survival was 2.3 months. The most common grade ≥3 adverse event was elevation of alanine aminotransferase (two patients, 8%). Diarrhea/colitis was seen in three patients and was grade 1-2. There was one adverse event leading to death (hypoxia).

Conclusions

Idelalisib was tolerable and had modest single-agent activity in heavily pretreated patients with HL. Rational combinations with other novel agents may improve response rate and duration of response.

Clinical trial registration

ClinicalTrials.gov # NCT01393106.

Biology of classical Hodgkin lymphoma: implications for prognosis and novel therapies

Hodgkin lymphoma is considered a prime example of treatment success, with cure rates exceeding 80% using modern combined modality therapies. However, especially in adolescents and young adults, treatment-related toxicity and long-term morbidity still represent persistent challenges. Moreover, outcomes in patients with relapsed or refractory disease remain unfavorable in the era of high-dose chemotherapy and stem-cell transplantation. Hence, there is a high demand for novel and innovative alternative treatment approaches. In recent years, many new therapeutic agents have emerged from preclinical and clinical studies that target molecular hallmarks of Hodgkin lymphoma, including the aberrant phenotype of the tumor cells, deregulated oncogenic pathways, and immune escape. The antibody-drug conjugate brentuximab vedotin and immune checkpoint inhibitors have already shown great success in patients with relapsed/refractory disease, leading to US Food and Drug Administration approval and new trials testing these agents in various clinical settings. The expanding knowledge and understanding of Hodgkin lymphoma biology and disease progression, as well as the development of robust tools for biomarker-driven risk stratification and therapeutic decision making, continue to be fundamentally important for the success of these and other novel agents. We anticipate that the availability and clinical implementation of novel molecular assays will be instrumental in an era of rapid shifts in the treatment landscape of this disease. Here, we review the current knowledge of Hodgkin lymphoma pathobiology, highlighting the related development of novel treatment strategies and prognostic models that hold the promise to continually challenge and change the current standard of care in classical Hodgkin lymphoma.

Brentuximab vedotin in relapsed/refractory Hodgkin lymphoma. The Hellenic experience

This retrospective study aimed to describe the Hellenic experience on the use of brentuximab vedotin (BV) in relapsed/refractory (R/R) Hodgkin lymphoma (HL) given within its indication. From June 2011 to April 2015, ninety-five patients with R/R HL, who received BV in 20 centers from Greece, were analyzed. Their median age was 33 years, and 62% were males. Sixty-seven patients received BV after autologous stem cell transplantation failure, whereas 28 patients were treated with BV without a prior autologous stem cell transplantation, due to advanced age/comorbidities or chemorefractory disease. The median number of prior treatments was 4 and 44% of the patients were refractory to their most recent therapy. The median number of BV cycles was 8 (range, 2-16), and the median time to best response was the fourth cycle. Fifty-seven patients achieved an objective response: twenty-two (23%), a complete response (CR), and 35 patients (37%), a partial, for an overall response rate of 60%. Twelve patients (13%) had stable disease, and the remaining twenty-six (27%) had progressive disease as their best response. At a median follow-up of 11.5 months, median progression-free survival and overall survival were 8 and 26.5 months, respectively. Multivariate analysis showed that chemosensitivity to treatment administered before BV was associated with a significantly increased probability of achieving response to BV (P = .005). Bulky disease (P = .01) and response to BV (P <.001) were significant for progression-free survival, while refractoriness to most recent treatment (P = .04), bulky disease (P = .005), and B-symptoms (P = .001) were unfavorable factors for overall survival. Among the 22 CRs, 5 remain in CR with no further treatment after BV at a median follow-up of 13 months. In conclusion, our data indicate that BV is an effective treatment for R/R HL patients even outside clinical trials. Whether BV can cure a fraction of patients remains to be seen.

PD-1 /PD-L1 checkpoint in hematological malignancies

Programmed cell death protein 1 (PD-1), is a cell surface receptor with an important role in down-regulating the immune system and promoting self-tolerance by suppressing T cell inflammatory activity. PD-1/PDL1 axis represents a checkpoint to control immune responses and it is often used as a mechanism of immune escaping by cancers and infectious diseases. Many data demonstrate its important role in solid tumors and report emerging evidences in lymphoproliferative disorders. In this review, we summarized the available data on the role of PD-1/PD-L1 checkpoint in lymphoproliferative diseases and the therapeutics use of monoclonal blocking antibodies.

A novel enediyne-integrated antibody-drug conjugate shows promising antitumor efficacy against CD30+ lymphomas

CD30 is a 120-kDa type I transmembrane glycoprotein belonging to the tumor necrosis factor receptor superfamily. Overexpression of CD30 has been reported in Hodgkin's lymphoma (HL) and anaplastic large-cell lymphoma (ALCL). CD30-targeted treatment with antibody-drug conjugates (ADCs) can lead to promising clinical benefit. Lidamycin (LDM), consisting of an apoprotein LDP and an active enediyne chromophore AE, is a member of the enediyne antibiotic family and one of the most potent antitumor agents. AE and LDP can be dissociated and reconstituted under certain conditions in vitro. LDM is an ideal payload for the preparation of ADCs. In this study, we show the generation, production, and antitumor activity of anti-CD30-LDM, a novel ADC which consists of the intact anti-CD30 antibody and LDM. First, the anti-CD30-LDP fusion protein was constructed and expressed in CHO/dhFr^- cells. Anti-CD30-LDP showed specific and high-affinity binding to CD30 and could be internalized into target cells. It also exhibited excellent tumor-targeting capability in vivo. Next, anti-CD30-LDM was prepared by assembling the enediyne molecule AE to the fusion protein anti-CD30-LDP. Anti-CD30-LDM was highly cytotoxic to HL and ALCL cell lines, with IC₅₀ values of 5-50 pm. It can also induce cell apoptosis and G2/M cell cycle arrest. In the Karpas299 xenograft model, the tumor growth was inhibited by 87.76% in mice treated with anti-CD30-LDM and with no discernible adverse effects. Taken together, anti-CD30-LDM shows attractive tumor-targeting capability and antitumor efficacy both in vitro and in vivo and could be a promising candidate for the treatment of CD30⁺ lymphomas.

SOHO State of the Art Updates and Next Questions: Hodgkin Lymphoma

Until recently, advances in classic Hodgkin lymphoma (HL) treatment primarily consisted of minor modifications of highly effective decades-old chemotherapy and radiation approaches. In early-stage disease, excellent outcomes have been reported with fewer cycles of chemotherapy, lower doses, smaller radiation fields and in some circumstances, radiation elimination. In advanced-stage disease, maintaining the dose intensity of standard chemotherapy regimens has resulted in modest improvements in outcomes. During the past decade, the use of early interim positron emission tomography (PET) scans to escalate or de-escalate treatment has been the subject of intense investigation with the goal of maximizing efficacy and minimizing toxicity. Important updates from recent PET-directed trials include; elimination of bleomycin in patients with advanced-stage HL and negative interim PET findings, the benefit of therapy escalation in patients with unfavorable early-stage HL and positive interim PET findings, and the minimal benefit of consolidative radiotherapy in patients with unfavorable early-stage HL and negative interim PET findings. A more nuanced approach to consolidative radiotherapy is required for patients with favorable early-stage disease based on age, disease sites, secondary cancer risk, and cardiovascular disease. Brentuximab vedotin and nivolumab/pembrolizumab have provided promising new options with surprisingly high response rates and modest toxicity for patients with relapsed HL whose disease does not respond to standard treatments. Incorporating these agents into earlier therapy is an area of active investigation for all stages of HL. Although the overall prognosis for HL patients has seen incremental improvement, efforts to optimize treatment with more effective and less toxic approaches continue.

Brentuximab vedotin: clinical updates and practical guidance

Brentuximab vedotin (BV), a potent antibody-drug conjugate, targets the CD30 antigen. Owing to the remarkable efficacy shown in CD30-positive lymphomas, such as Hodgkin's lymphoma and systemic anaplastic large-cell lymphoma, BV was granted accelerated approval in 2011 by the US Food and Drug Administration. Thereafter, many large-scale trials in various situations have been performed, which led to extensions of the original indication. The aim of this review was to describe the latest updates on clinical trials of BV and the in-practice guidance for the use of BV.

Emerging role of novel therapies in Hodgkin lymphoma: proceed with caution

Based on very high response rates in the relapsed and refractory setting, brentuximab vedotin and the programmed cell death protein 1 (PD-1) inhibitors, nivolumab and pembrolizumab, have quickly been incorporated into clinical trials for first- and second-line therapy of Hodgkin lymphoma. Preliminary data show that brentuximab vedotin alone is not adequate therapy for newly diagnosed Hodgkin lymphoma in older patients, but modestly decreases the risk of relapse when combined with adriamycin, vinblastine, and dacarbazine in patients with previously untreated advanced-stage disease. In second-line therapy, combining brentuximab vedotin with conventional chemotherapy or with PD-1 inhibitors as pretransplant salvage is associated with high overall and complete response rates, although further follow up is needed to assess whether posttransplant outcomes are improved. Although these new drugs are well tolerated when given as single agents, unexpected toxicities have been encountered with combination regimens, specifically severe pulmonary toxicity with the bleomycin and brentuximab vedotin combination and frequent infusion-related reactions. There is concern with the use of PD-1 inhibitors as first-line therapy due to the theoretical potential for more frequent or severe immune-mediated toxicities in patients who have not received prior chemotherapy. Aside from these concerns, these new agents have the potential to improve outcomes for patients even further, bringing us closer to eradicating recurrent Hodgkin lymphoma.

Incorporation of brentuximab vedotin into first-line treatment of advanced classical Hodgkin's lymphoma: final analysis of a phase 2 randomised trial by the German Hodgkin Study Group

BACKGROUND

A high proportion of patients with relapsed classical Hodgkin's lymphoma achieve a response with the antibody-drug conjugate brentuximab vedotin, and the drug is well tolerated. We modified the escalated BEACOPP regimen (eBEACOPP; bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone) and implemented brentuximab vedotin with the aim to reduce toxic effects while maintaining the protocol's efficacy.

METHODS

We did an open-label, multicentre, randomised phase 2 study at 20 study sites in Germany. Adult patients (aged 18-60 years) with newly diagnosed, advanced, classical Hodgkin's lymphoma were randomly assigned (1:1) to treatment with six cycles of either BrECAPP (brentuximab vedotin 1·8 mg/kg on day 1, etoposide 200 mg/m² on days 2-4, doxorubicin 35 mg/m² on day 2, cyclophosphamide 1250 mg/m² on day 2, procarbazine 100 mg/m² on days 2-8, and prednisone 40 mg/m² on days 2-15) or BrECADD (brentuximab vedotin 1·8 mg/kg on day 1, etoposide 150 mg/m² on days 2-4, doxorubicin 40 mg/m² on day 2, cyclophosphamide 1250 mg/m² on day 2, dacarbazine 250 mg/m² on days 3-4, and dexamethasone 40 mg on days 2-5). Randomisation was done centrally by stratified minimisation, with study site and sex as stratification factors. The co-primary endpoints were complete response to chemotherapy and complete remission at the end of treatment, which were assessed by intention to treat. Patients who were found not to meet inclusion criteria after randomisation or without restaging data after two cycles of study treatment were excluded from the primary endpoint analysis. All patients who started study treatment were assessable for safety. This report presents the final analysis at a median follow-up of 17 months (IQR 13·2-21·5). The preplanned 2-year follow-up analysis is yet to be reported. This trial is registered with ClinicalTrials.gov, number NCT01569204.

FINDINGS

Between Oct 26, 2012, and May 15, 2014, 104 patients were enrolled to the study (52 were assigned to each study arm). Two patients dropped out before the start of study treatment because of acute infection (n=1) and withdrawal of consent (n=1) and one patient was excluded because of intermediate-stage disease (all were assigned BrECAPP). 42 (86%, 95% CI 73-94) of 49 patients assigned BrECAPP achieved a complete response after chemotherapy and 46 (94%, 95% CI 83-99) had complete remission as their final treatment outcome. In the BrECADD group, 46 (88%, 95% CI 77-96) of 52 patients achieved both a complete response after chemotherapy and complete remission as their final treatment outcome. 58 serious adverse events were reported, 32 events in 21 of 50 patients who received BrECAPP and 26 events in 18 of 52 patients who received BrECADD. The most common grade 3-4 toxic effects were haematological adverse events (91 [89%] of 102 patients). Grade 3-4 organ toxic effects were reported in seven (17%) of 42 patients assigned BrECAPP and two (4%) of 46 allocated BrECADD. 16 (32%) of 50 patients assigned BrECAPP and 18 (35%) of 52 allocated BrECADD had grade 1-2 peripheral neuropathy, and one (2%) patient assigned BrECAPP developed grade 3 peripheral neuropathy; all but one case (allocated BrECAPP) resolved. No deaths were reported during the follow-up period.

INTERPRETATION

Both eBEACOPP variants met the co-primary efficacy endpoints. Particularly, the BrECADD regimen was associated with a more favourable toxicity profile and was, therefore, selected to challenge standard eBEACOPP for the treatment of advanced classical Hodgkin's lymphoma in the phase 3 HD21 study by the German Hodgkin Study Group (NCT02661503), which aims to further reduce treatment-related morbidity.

FUNDING

Takeda Pharmaceuticals.

Italian real life experience with brentuximab vedotin: results of a large observational study on 234 relapsed/refractory Hodgkin's lymphoma

A large Italian multicenter observational retrospective study was conducted on the use of brentuximab vedotin (BV) for patients with relapsed Hodgkin's lymphoma (HL) to check if clinical trial results are confirmed even in a real life context. 234 CD30+ HL patients were enrolled. Best response was observed after a median of 4 cycles in 140 patients (59.8%): 74 (31.6%) patients obtained a complete response (CR) and 66 (28.2%) achieved a partial response (PR); overall response rate at the end of the treatment was 48.3% (62 CR and 51 PR). The best response rate was higher in the elderly subset: 14 (50%) CR and 5 (17.8%) PR. Disease free survival was 26.3% at 3 years and progression free survival 31.9% at 4.5 years. Duration of response did not differ for who achieved at least PR and then either did or did not undergo consolidative transplant. Overall, the treatment was well tolerated and no death has been linked to BV-induced toxicity. Our report confirms activity in elderly patients, duration of response unrelated to the consolidation with transplant procedure, the relevance of the CR status at first restaging, and the role of BV as a bridge to transplant for chemorefractory patients.

Recent treatment advances in Hodgkin lymphoma: a concise review

The majority of patients with Hodgkin lymphoma enjoy durable remissions following front-line treatment. This typically involves combination chemotherapy with or without radiotherapy. A significant minority of patients experience relapsed/refractory disease, of whom only approximately half can be 'salvaged' with conventional second-line treatments. Until recently, for those patients either failing or who are not fit for salvage, there have been few curative alternatives. Furthermore, there is a significant risk of delayed treatment complications to conventional therapies, including secondary malignancies and cardiac disease. However, novel targeted therapies are producing excellent results in clinical trials. They provide additional treatment options for those with relapsing/refractory disease; they may have potential in front-line therapy. The anti-CD30 antibody brentuximab vedotin (BV) has been tested as monotherapy and in combination in a variety of clinical settings, including in relapsed/refractory patients and as consolidative therapy following standard second-line therapy. Nivolumab and pembrolizumab, currently used in other malignancies that are known to utilise the programmed death pathway for survival, have shown outstanding results when used as single agents in heavily pre-treated (including BV refractory) patients. Individualising and adapting a patient's treatment course, whether augmenting or rationalising therapy, based on an interim positron emission tomography/computed tomography response is an important strategy currently under exploration to minimise toxicity while maximising response. Further work is needed to explore clinical and biological factors associated with improved outcomes. Knowledge of these factors combined with the movement of novel therapies into the front-line setting will enable individualised therapy to enhance clinical responses and minimise toxicities.

Treatment patterns and costs of care for patients with relapsed and refractory Hodgkin lymphoma treated with brentuximab vedotin in the United States: A retrospective cohort study

OBJECTIVES

Although brentuximab vedotin (BV) has changed the management of patients with relapsed or refractory Hodgkin lymphoma (RRHL), little information is available on routine clinical practice. We identified treatment patterns and costs of care among RRHL patients in the United States (US) treated with BV.

METHODS

A retrospective observational study of adults initiating BV for RRHL from 2011-2015, with ≥6 months of data prior to and following BV initiation, was conducted. Treatments were classified based on dispensations and chemotherapy administration. Median total and monthly costs were estimated based on all-cause healthcare resource use in 2015 US dollars (USD).

RESULTS

The cohort comprised 289 patients (59% male; mean age at diagnosis, 42 years) with a mean follow-up of 250 weeks. Eleven percent had BV salvage therapy prior to ASCT, and 32% had BV for a relapse post-ASCT. 43% received treatment post-BV, most commonly allogeneic stem cell transplant (SCT) and bendamustine (both 10.2%). Median (IQR) total costs from BV initiation to censoring were 294,790 (142,110-483,360) USD; and were highest among those treated with BV prior to ASCT (up to 421,900 [300,940-778,970] USD). Median monthly costs were almost 20,000 USD per month, and up to 25,000 USD per month among those with BV and ASCT. Medications were the greatest driver of median monthly costs.

CONCLUSIONS

Median total all-cause costs were almost 300,000 USD, and median monthly costs approximately 20,000 USD, per patient treated. Patients requiring treatment following BV continue to incur high costs, highlighting the economic burden associated with managing patients in the RRHL setting.

Cost-effectiveness analysis of consolidation with brentuximab vedotin for high-risk Hodgkin lymphoma after autologous stem cell transplantation

BACKGROUND

In a recent randomized, placebo-controlled trial, consolidation treatment with brentuximab vedotin (BV) decreased the risk of Hodgkin lymphoma (HL) progression after autologous stem cell transplantation (ASCT). However, the impact of BV consolidation on overall survival, quality of life, and health care costs remain unclear.

METHODS

A Markov decision-analytic model was constructed to measure the costs and clinical outcomes for BV consolidation therapy compared with active surveillance in a cohort of patients aged 33 years who were at risk for HL relapse after ASCT. Life-time costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs) were calculated for each post-ASCT strategy.

RESULTS

After quality-of-life adjustments and standard discounting, upfront BV consolidation was associated with an improvement of 1.07 QALYs compared with active surveillance plus BV as salvage. However, the strategy of BV consolidation led to significantly higher health care costs ($378,832 vs $219,761), resulting in an ICER for BV consolidation compared with active surveillance of $148,664/QALY. If indication-specific pricing was implemented, then the model-estimated BV price reductions of 18% to 38% for the consolidative setting would translate into ICERs of $100,000 and $50,000 per QALY, respectively. These findings were consistent on 1-way and probabilistic sensitivity analyses.

CONCLUSIONS

BV as consolidation therapy under current US pricing is unlikely to be cost effective at a willingness-to-pay threshold of $100,000 per QALY. However, indication-specific price reductions for the consolidative setting could reduce ICERs to widely acceptable values. Cancer 2017. © 2017 American Cancer Society. Cancer 2017;123:3763-3771. © 2017 American Cancer Society.

Attachment Site Cysteine Thiol pKa Is a Key Driver for Site-Dependent Stability of THIOMAB Antibody-Drug Conjugates

The incorporation of cysteines into antibodies by mutagenesis allows for the direct conjugation of small molecules to specific sites on the antibody via disulfide bonds. The stability of the disulfide bond linkage between the small molecule and the antibody is highly dependent on the location of the engineered cysteine in either the heavy chain (HC) or the light chain (LC) of the antibody. Here, we explore the basis for this site-dependent stability. We evaluated the in vivo efficacy and pharmacokinetics of five different cysteine mutants of trastuzumab conjugated to a pyrrolobenzodiazepine (PBD) via disulfide bonds. A significant correlation was observed between disulfide stability and efficacy for the conjugates. We hypothesized that the observed site-dependent stability of the disulfide-linked conjugates could be due to differences in the attachment site cysteine thiol pK_a. We measured the cysteine thiol pK_a using isothermal titration calorimetry (ITC) and found that the variants with the highest thiol pK_a (LC K149C and HC A140C) were found to yield the conjugates with the greatest in vivo stability. Guided by homology modeling, we identified several mutations adjacent to LC K149C that reduced the cysteine thiol pK_a and, thus, decreased the in vivo stability of the disulfide-linked PBD conjugated to LC K149C. We also present results suggesting that the high thiol pK_a of LC K149C is responsible for the sustained circulation stability of LC K149C TDCs utilizing a maleimide-based linker. Taken together, our results provide evidence that the site-dependent stability of cys-engineered antibody-drug conjugates may be explained by interactions between the engineered cysteine and the local protein environment that serves to modulate the side-chain thiol pK_a. The influence of cysteine thiol pK_a on stability and efficacy offers a new parameter for the optimization of ADCs that utilize cysteine engineering.

Outcomes of patients with relapsed/refractory Hodgkin lymphoma progressing after autologous stem cell transplant in the current era of novel therapeutics: A retrospective analysis

Patients with relapsed/refractory Hodgkin lymphoma (RR-HL) who progress or relapse following autologous stem cell transplantation (ASCT) have historically had a poor prognosis. Several novel agents, particularly brentuximab vedotin, have shown efficacy in this setting. However, there remains a paucity of data characterizing outcomes outside of clinical trials and how these novel agents have impacted prognosis in general population of patients with RR-HL. Here, we conducted a retrospective analysis to evaluate outcomes in 87 patients with RR-HL with relapse post-ASCT. Treatment with novel agents (including brentuximab vedotin) was associated with significant improvement in median overall survival (OS) compared to patients who did not receive novel agents (85.6 vs 17.1 months; P < .001). Additional factors associated with improved OS in univariate analysis include treatment with radiation therapy post-ASCT (34.1 vs 17.0 months; P = .015), chemosensitivity (i.e., relapsed compared to primary refractory disease; 51.8 vs 25.6 months; p = 0.013), initial response to ASCT (i.e., CR/PR compared to SD/PD; 46.1 vs 20.4 months; P = .011), and transplantation in 2010 and later compared to prior to 2010 (not reached vs 24.5 months; P = .025). The current study demonstrates markedly improved OS in RR-HL patients treated with novel therapeutics and lends "real world" credence to the role of these agents in improving outcomes in the current era.

Current developments in the treatment of early-stage classical Hodgkin lymphoma

PURPOSE OF REVIEW

After presenting the current treatment recommendations for early-stage Hodgkin lymphoma, we give an overview on recently published clinical trials in this setting. Furthermore, the potential influence of current trials on the treatment of early-stage Hodgkin lymphoma and integration of newly emerging drugs into treatment protocols will be discussed.

RECENT FINDINGS

Trials attempting treatment de-escalation and omission of radiotherapy on the basis of early interim PET-scans have been disappointing so far, but results of some large trials employing this strategy are still awaited. In contrast, a more defensive strategy of starting treatment with less aggressive doxorubicine, bleomycin, vinblastine, dacarbazine (ABVD) chemotherapy and intensifying treatment in early interim PET-positive patients has shown encouraging results. New drugs such as brentuximab vedotin and immune checkpoint inhibitors have shown promising results in relapsed and refractory Hodgkin lymphoma. Clinical trials of brentuximab vedotin in early-stage Hodgkin lymphoma have been initiated. Additionally, biomarker-based treatment de-escalation might be a possible route for future improvements.

SUMMARY

The challenge for future clinical research in early-stage Hodgkin lymphoma is to continue to cure the majority of patients with first-line treatment while reducing long-term toxicity. New strategies to achieve that goal are currently being developed and will further refine treatment of early-stage Hodgkin lymphoma.

The evolving role of targeted drugs in the treatment of Hodgkin lymphoma

INTRODUCTION

Hodgkin lymphoma (HL) is a B-cell-derived malignancy mostly affecting young adults. More than 80% of patients are cured after stage-adapted first-line treatment with chemotherapy and/or radiotherapy. About 50% of patients with disease recurrence achieve long-term remission with second-line treatment consisting of high-dose chemotherapy and autologous stem cell transplantation. However, HL treatment is often associated with acute toxicity and in part life-threatening late effects. Implementing targeted drugs may reduce toxicity and potentially further optimize efficacy. In recent years, the CD30-directed antibody-drug conjugate brentuximab vedotin (BV) and anti-PD-1 antibodies, nivolumab and pembrolizumab, underwent extensive evaluation in HL. They have exhibited encouraging single agent activity and a favorable toxicity profile in patients with multiple relapses. Therefore, they are currently under investigation in different additional indications. Areas covered: This article gives an overview over clinical trials evaluating targeted drugs either as single agent or as part of combination therapies in HL patients. Expert commentary: A multitude of targeted drugs are investigated in HL. Promising data have particularly emerged from studies with BV and anti-PD-1 antibodies. However, mature data needed for final conclusions are still pending.

An Updated Review on Marine Anticancer Compounds: The Use of Virtual Screening for the Discovery of Small-Molecule Cancer Drugs

Marine secondary metabolites are a promising source of unexploited drugs that have a wide structural diversity and have shown a variety of biological activities. These compounds are produced in response to the harsh and competitive conditions that occur in the marine environment. Invertebrates are considered to be among the groups with the richest biodiversity. To date, a significant number of marine natural products (MNPs) have been established as antineoplastic drugs. This review gives an overview of MNPs, both in research or clinical stages, from diverse organisms that were reported as being active or potentially active in cancer treatment in the past seventeen years (from January 2000 until April 2017) and describes their putative mechanisms of action. The structural diversity of MNPs is also highlighted and compared with the small-molecule anticancer drugs in clinical use. In addition, this review examines the use of virtual screening for MNP-based drug discovery and reveals that classical approaches for the selection of drug candidates based on ADMET (absorption, distribution, metabolism, excretion, and toxicity) filtering may miss potential anticancer lead compounds. Finally, we introduce a novel and publically accessible chemical library of MNPs for virtual screening purposes.

A Phase I/II Trial of Panobinostat in Combination With Lenalidomide in Patients With Relapsed or Refractory Hodgkin Lymphoma

BACKGROUND

Lenalidomide and panobinostat have shown single-agent efficacy of 14% to 50% and 27% to 58%, respectively, in Hodgkin lymphoma (HL). This phase I/II study was conducted to determine the maximum tolerated dose (MTD), safety, and efficacy of lenalidomide combined with panobinostat in relapsed/refractory HL.

PATIENTS AND METHODS

In the phase I trial, previously treated patients with classical or lymphocyte-predominant HL received escalating doses of lenalidomide on days 1 to 21 and panobinostat 3 times a week (TIW) every 28 days. Dose-limiting toxicity (DLT) was defined during cycle 1. When the MTD was determined, a phase II study was conducted to determine overall response (OR).

RESULTS

Twenty-four patients enrolled; 11 in the phase I and 13 in phase II portions. No DLTs were observed but 2 patients who received 25 mg lenalidomide and 20 mg panobinostat experienced neutropenia and thrombocytopenia > 14 days in cycle 2, leading to selection of 25 mg lenalidomide on days 1 to 21 and 15 mg panobinostat TIW for the phase II dose. In all 24 patients, Grade 3 to 4 toxicities consisted of neutropenia (58%), thrombocytopenia (42%), lymphopenia (25%), and febrile neutropenia (25%). OR was 16.7% (2 complete response [CR] and 2 partial response). One patient with CR had lymphocyte-predominant HL and received 22 cycles. Median progression-free survival and overall survival were 3.8 and 16.4 months, respectively.

CONCLUSION

Although the combination of panobinostat and lenalidomide appears safe in patients with relapsed/refractory HL, the limited efficacy and significant rates of neutropenia and febrile neutropenia observed do not support further evaluation of this combination in HL.

New drugs and allogeneic hematopoietic stem cell transplantation for hematological malignancies: do they have a role in bridging, consolidating or conditioning transplantation treatment?

INTRODUCTION

Novel targeted therapies and monoclonal antibodies can be combined with allogeneic stem cell transplantation (allo-SCT) at different time-points: 1) before the transplant to reduce tumour burden, 2) as part of the conditioning in place of or in addition to conventional agents 3) after the transplant to allow long-term disease control. Areas covered: This review focuses on the current integration of new drugs with allo-SCT for the treatment of major hematological malignancies for which allo-SCT has been a widely-adopted therapy. Expert opinion: After having been used as single agent salvage treatments in relapsed patients after allo-SCT or in combination with donor lymphocyte infusions, many new drugs have also been safely employed before allo-SCT as a bridge to transplantation or after it as planned consolidation/maintenance. This era of new drugs has opened new important opportunities to 'smartly' combine 'targeted drugs and cell therapies' in new treatment paradigms that may lead to higher cure rates or longer disease control in patients with hematological malignancies.

Emerging treatment options for the management of Hodgkin's lymphoma: clinical utility of nivolumab

Classical Hodgkin's lymphoma (cHL) is a B-cell malignancy comprised of pathologic Reed Sternberg cells with a surrounding immune-tolerant inflammatory milieu. RS cells evade immune recognition in part through programmed death ligand 1 (PD-L1) overexpression, which is genetically programmed through copy number alterations, polysomy, and amplification of the 9p24.1 locus encoding PD-L1. By engaging with PD-1+ T-cells, PD-L1 delivers a potent immune suppressive signal promoting immunologic escape of the tumor cell. Enhancing antitumor immune response by targeting PD-1 with the monoclonal antibody nivolumab has proved to be effective in multiple solid tumors, but the highest response rates to date have been reported in patients with cHL, with over 65% of treated patients achieving an objective clinical response. In this review, we will summarize the published evidence regarding the activity of nivolumab in cHL as well as its current place in therapy. We will review the pharmacology, mechanism of action, and side effects of nivolumab as well as the emerging data indicating possible increased risk of graft versus host disease in patients treated with PD-1 inhibitors either pre- or post-allogeneic stem cell transplant. Given the remarkable single-agent activity and safety profile of PD-1 inhibitors in heavily pretreated patients with cHL, the possibility of employing nivolumab in combination with other active agents and earlier in therapy is a promising area of active investigation, and we will briefly summarize current clinical trials.