Lenalidomide in patients with refractory or multiple relapsed Hodgkin lymphoma

Romidepsin and lenalidomide-based regimens have efficacy in relapsed/refractory lymphoma: Combined analysis of two phase I studies with expansion cohorts

Romidepsin (histone deacetylase inhibitor), lenalidomide (immunomodulatory agent), and carfilzomib (proteasome inhibitor), have efficacy and lack cumulative toxicity in relapsed/refractory lymphoma. We performed two investigator initiated sequential phase I studies to evaluate the maximum tolerated dose (MTD) of romidepsin and lenalidomide (regimen A) and romidepsin, lenalidomide, and carfilzomib (regimen B) in relapsed/refractory lymphoma. Cohorts in T-cell lymphoma (TCL), B-cell lymphoma (BCL) were enrolled at the MTD. Forty-nine patients were treated in study A (27 TCL, 17 BCL, 5 Hodgkin lymphoma (HL)) and 27 (16 TCL, 11 BCL) in study B. The MTD of regimen A was romidepsin 14 mg/m² IV on days 1, 8, and 15 and lenalidomide 25 mg oral on days 1-21 of a 28-day cycle. The MTD of regimen B was romidepsin 8 mg/m² on days 1 and 8, lenalidomide 10 mg oral on days 1-14 and carfilzomib 36 mg/m² IV on days 1 and 8 of a 21-day cycle. In study A, 94% had AEs ≥Grade 3, most commonly neutropenia (49%), thrombocytopenia (53%), and electrolyte abnormalities (49%). In study B 59% had AEs ≥Grade 3, including thrombocytopenia (30%) and neutropenia (26%). In study A the ORR was 49% (50% TCL, 47% BCL, 50% HL). In study B the ORR was 48% (50% TCL, 50% BCL). For study A and B the median progression free survival (PFS) was 5.7 months and 3.4 months respectively with 11 patients proceeding to allogeneic transplant. The combinations of romidepsin and lenalidomide and of romidepsin, lenalidomide and carfilzomib showed activity in relapsed/refractory lymphoma with an acceptable safety profile.

Outcome of relapsed and refractory nodular lymphocyte-predominant Hodgkin lymphoma: a North American analysis

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare entity, with limited data on the outcome in the relapsed/refractory setting. We evaluated the outcome of all patients diagnosed between 04/1979 and 01/2019 with relapsed or progressive NLPHL after initial active therapy at two institutions, refractory disease being defined as lack of response to treatment and/or relapse within three months of treatment. NLPHL patients with histological evidence of transformation at time of first relapse or progression were excluded. In total, 69 patients with recurrent NLPHL were included in the study. After a median follow-up after initial diagnosis of 14 years (range, 0·5-46 years), median progression-free survival after front-line treatment (PFS-1) was four years. Second-line therapy included chemotherapy in 28 (41%) patients, biological therapy (rituximab, lenalidomide or brentuximab vedotin) in 14 (20%), high-dose chemotherapy followed by autologous stem cell transplant in 14 (20%) and radiation therapy (RT) alone in 10 (15%). The five-year PFS after second-line therapy (PFS-2) was 68% [95% confidence interval (CI), 54-79%] but the five-year overall survival (OS) after second-line therapy (OS-2) remained excellent, at 94% (95% CI, 85-99%). Due to excellent outcome in case of recurrence, studies aimed at characterizing its biology to guide therapy de-escalation are needed.

Low dose continuous lenalidomide in heavily pretreated patients with relapsed or refractory classical Hodgkin lymphoma: a retrospective case series

Patients with relapsed or refractory (R/R) classical Hodgkin lymphoma (cHL) following autologous stem cell transplant (ASCT) remain a management challenge with few reliably effective treatments. Lenalidomide, an immunomodulatory drug approved for patients with myelodysplastic syndrome with del(5q), multiple myeloma, and mantle cell lymphoma, has demonstrated some activity in patients with R/R cHL, though the toxicity of traditional doses and schedules has been a barrier to consistent use. Low dose continuous (LDC) schedules have emerged as promising, with a more favorable safety profile. We report herein that LDC schedules are associated with a far more tolerable toxicity profile, and exhibit at least equivalent efficacy in this patient population. We report that patients diagnosed with R/R cHL who previously underwent, or were not candidates for, ASCT and/or clinical trials, were administered daily LDC lenalidomide (20 mg orally with dose reduction for toxicity). Among the 19 patients included in this analysis, 11% of patients achieved a partial response (PR), with no documented complete responses (CR). A total of 12 (63%) patients maintained stable disease (SD), with 7 patients (37%) remaining in SD for more than 6 months. The clinical benefit rate (comprised of CR, PR, and SD for greater than 6 months) was 47% (7 out of 19 patients). The median progression-free survival and overall survival of all patients were 9.4 months (range, 4.6–14.4 months) and 90 months (range, 63.6–166.8 months), respectively. In general, the treatment was well tolerated, with grade 3 or 4 adverse events consisting of neutropenia (n = 4), and one case each of thrombocytopenia, fatigue, rash, creatinine elevation, aspartate transaminase/alanine transaminase elevation, and treatment related secondary malignancy. In a heavily treated R/R cHL patient population, daily LDC lenalidomide was associated with a high disease control rate with a favorable toxicity profile.

Hodgkin lymphoma in elderly patients

PURPOSE OF REVIEW

We aim to summarize the current knowledge on the treatment of elderly Hodgkin lymphoma patients with a focus on evidence from clinical trials and novel drugs.

RECENT FINDINGS

For elderly Hodgkin lymphoma patients above 60 years without precluding comorbidities a curative treatment approach is warranted. Early favorable stage patients should receive two cycles of multiagent chemotherapy followed by 20 Gy localized radiotherapy. Early unfavorable stage patients should receive four cycles of multiagent chemotherapy followed by 30 Gy localized radiotherapy. For advanced stage patients six cycles of multiagent chemotherapy can be recommended and should be followed by localized radiotherapy on residual disease manifestations. Relapsed or refractory patients should be treated in an individually tailored approach that considers both the patient's objectives and comorbidities. The antibody-drug conjugate brentuximab vedotin is a very effective option for elderly patients with a high response rate albeit limited durability. Anti-programed cell death protein 1 antibodies might also be effective in elderly Hodgkin lymphoma patients with a mechanism of action distinct from chemotherapy.

SUMMARY

In conclusion, the goal of treatment in newly diagnosed elderly Hodgkin lymphoma patients is curative whenever possible and prospective and retrospective evidence has shown that this is feasible for all disease stages with a variety of multiagent chemotherapy regimen. Relapsed and refractory elderly Hodgkin lymphoma patients can mostly only be treated with the goal of palliation. However, it remains to be seen if novel substances and new combination regimen are able to change that.

Moving things forward in Hodgkin lymphoma

Arising from the immune system and located primarily in lymphoid organs, Hodgkin lymphoma (HL) is one of the most common cancers in young adults. Risk-adapted first-line treatment usually consisting of multi-agent chemotherapy and often incorporating consolidative radiation therapy aims at long-term cure. Although this is achieved in the vast majority of patients, therapy-related side effects such as organ damage, second cancers, and fatigue constitute considerable sequelae and outweigh HL as the cause of mortality after successful first-line treatment. In addition, intensive conventional therapy is seldom feasible in elderly or frail patients, diminishing chances of cure in this growing population of patients. The rapidly growing understanding of HL biology, innovative clinical trials, and the incorporation of novel drugs might help to overcome these obstacles in the management of HL. In this review, recent advances in the understanding and care of HL will be summarized with a focus on ongoing and future strategies which might help move things forward.

Complete response associated with lenalidomide and celecoxib in a case of primary refractory Hodgkin lymphoma

Hodgkin lymphoma (HL) represents ~11% of all lymphoma cases. This disease occurs in young adults, but also affects people over 55 years of age. Despite the fact that >80% of all newly diagnosed patients under 60 will achieve a sustained complete response (CR), 5%-10% of HL patients are refractory to initial treatment and 10%-30% of patients will eventually relapse after an initial CR. The treatment recommendation for primary refractory or relapsed HL patients is salvage therapy followed by high-dose chemotherapy and autologous stem cell transplantation. Following this approach, a significant part will still relapse at any moment. Thus, further research and new drugs or combinations are required. Overexpression of COX-2 has been associated with poor prognosis in relapse/refractory HL patients, so it could be a potential therapeutic target in HL. For this purpose, several drugs may have a role: specific COX-2 inhibitors such as celecoxib or other anti-inflammatory drugs such as lenalidomide may further inhibit lipopolysaccharide-mediated induction of COX-2. Moreover, lenalidomide and COX-2 inhibitors (celecoxib) have been tested in solid tumors with encouraging results. We present a case of a young female diagnosed with a heavily pretreated HL nodular sclerosis subtype who, after failing six treatment lines, only achieved clinical and radiological CR after six cycles of lenalidomide/celecoxib that resulted in an event-free survival of 22 months. We explain the rationale of using this chemotherapy regimen and our patient follow-up.

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.

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.

Everolimus as a single agent in refractory or relapsed Hodgkin's lymphoma: the Brazilian Named Patient Program Experience

Background

Despite all the scientific progress that has been made on understanding the disease, prognosis for patients with relapsed and refractory Hodgkin's lymphoma remains poor and the treatment is palliative in the majority of the cases. Thus, the aim of this study was to present the results on the compassionate use of everolimus in a group of patients who were monitored at nine different centers in Brazil.

Methods

A 10-mg oral dose of everolimus was given to each patient daily. Response time was evaluated from the beginning of medication use until loss of response, toxicity or medical decision to cease treatment.

Results

Thirty-three patients were evaluated. The median age at the beginning of medication administration was 29 years. Patients had received a median of five prior therapies. Overall response rate was 45.4%, with 13 patients achieving partial response, two achieved clinical response, 14 remained with stable disease, two had disease progression, and two were not evaluated. Patients received a median of 14 cycles. Progression-free survival was nine months, and overall survival was estimated to be 36 months. Three patients used the medication for more than four years. The most frequently reported adverse events were thrombocytopenia and hypercholesterolemia. Three patients had pulmonary toxicity. Grade III and IV adverse events occurred in 39% of the patients.

Conclusion

Everolimus was found to provide a response in a group of patients with refractory or relapsed Hodgkin's lymphoma who had adequate tolerability to the drug.

Novel agents in classical Hodgkin lymphoma

Classical Hodgkin lymphoma (cHL) is the most common hematological malignancy in young adults and can be cured in most cases. However, relapsed and refractory Hodgkin lymphoma, certain patient groups, such as elderly patients, and toxicity of first-line treatment still pose significant challenges. Consequently, new treatment options are needed. Recently, many new treatment concepts have been evaluated in clinical trials. Targeted drug-antibody conjugates and immune checkpoint inhibitors have decisively changed treatment approaches. This review aims to give a comprehensive overview of novel agents in Hodgkin lymphoma that have been recently or are currently being evaluated in clinical trials. In addition to dedicated sections on brentuximab vedotin (BV) and immune checkpoint inhibitors, other emerging substances and concepts are discussed. In doing so, this review compares trial results regarding safety and efficacy. A special focus lies on the effect novel agents will have on the different treatment settings faced by clinicians involved in the treatment of Hodgkin lymphoma.

Novel treatment concepts in Hodgkin lymphoma

Treatment of classical Hodgkin's lymphoma (HL) has been a success story, with cure of localized disease with radiotherapy in the 1930s, cure of advanced stages with combination chemotherapy with/without radiotherapy in the mid-1960s and continuous improvements since then. Nonetheless, at present approximately 2% of patients with classical HL are primarily refractory to conventional therapy with only 50% becoming long-term survivors. Another 13% of patients relapse, with only 60% being alive 10 years postrecurrence (as exemplified in this review in a Swedish cohort of 18- to 65-year-old patients diagnosed during the period 1992-2009). Recently, novel targeted drugs were approved for refractory/relapsed HL and here we review results of trials that form the basis for these approvals as well as new trials. In summary, brentuximab vedotin can be used in refractory patients (i) as a complement to high-dose chemotherapy with autologous stem cell transplantation (SCT) improving the chances of being able to proceed to an allogenic SCT and cure, (ii) as consolidation after autologous SCT and (iii) as palliative life-prolonging treatment. However, we have yet to determine whether this drug provides the greatest benefit in first- or second-line treatment, as consolidation or in refractory disease or relapse. Trials of immune checkpoint inhibitors, such as those targeting programmed death 1 (nivolumab and pembrolizumab), and thus not primarily the tumour cells, have shown overall response rates of >65%. Long-term results and data from Phase III trials are still lacking, but nivolumab recently gained approval in refractory patients already treated with brentuximab vedotin and autologous SCT. Other novel treatments of interest include T cells with a chimeric antigen receptor and combination therapies with histone deacetylase inhibitors.

Outcome of 1051 Octogenarian Patients With ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention: Observational Cohort From the London Heart Attack Group

BACKGROUND

ST-segment elevation myocardial infarction is increasingly common in octogenarians, and optimal management in this cohort is uncertain. This study aimed to describe the outcomes of octogenarians with ST-segment elevation myocardial infarction treated by primary percutaneous coronary intervention.

METHODS AND RESULTS

We analyzed 10 249 consecutive patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention between 2005 and 2011 at 8 tertiary cardiac centers across London, United Kingdom. The primary end point was all-cause mortality at a median follow-up of 3 years. In total, 1051 patients (10.3%) were octogenarians, with an average age of 84.2 years, and the proportion increased over the study period (P=0.04). In-hospital mortality (7.7% vs 2.4%, P<0.0001) and long-term mortality (51.6% vs 12.8%, P<0.0001) were increased in octogenarians compared with patients aged <80 years, and age was an independent predictor of mortality in a fully adjusted model (hazard ratio 1.07, 95% CI 1.07-1.09, P<0.0001). Time-stratified analysis revealed an increasingly elderly and more complex cohort over time. Nonetheless, long-term mortality rates among octogenarians remained static over time, and this may be attributable to improved percutaneous coronary intervention techniques, including significantly higher rates of radial access and lower bleeding complications. Variables associated with bleeding complications were similar between octogenarian and younger cohorts.

CONCLUSIONS

In this large registry, octogenarians undergoing primary percutaneous coronary intervention had a higher rate of complications and mortality compared with a younger population. Over time, octogenarians undergoing primary percutaneous coronary intervention increased in number, age, and complexity. Nevertheless, in-hospital outcomes were reasonable, and long-term mortality rates were static.

How I treat relapsed classical Hodgkin lymphoma after autologous stem cell transplant

Despite the success of standard front-line chemotherapy for classical Hodgkin lymphoma (cHL), a subset of these patients, particularly those with poor prognostic factors at diagnosis (including the presence of B symptoms, bulky disease, advanced stage, or extranodal disease), relapse. For those patients who relapse following autologous stem cell transplant (SCT), multiple treatment options are available, including single-agent chemotherapy, combination chemotherapy strategies, radiotherapy, the immunoconjugate brentuximab, checkpoint inhibitors nivolumab and pembrolizumab, lenalidomide, everolimus, or observation in selected patients. In patients with an available donor, allogeneic SCT may also be considered. With numerous treatment options available, we advocate for a tailored therapeutic approach for patients with relapsed cHL guided by patient-specific characteristics including age, comorbidities, sites of disease (nodal or organ), previous chemosensitivity, and goals of treatment (long-term disease control vs allogeneic SCT).

Genetic and molecular targets in lymphoma: implications for prognosis and treatment

Lymphomas are the most common hematologic malignancies with approximately 79,000 new cases estimated for 2013 in the USA. Despite improved outcomes, relapse or recurrence remains a common problem with conventional cytotoxic therapy. Recently, many genetic and molecular mechanisms that drive various cellular events like apoptosis, angiogenesis and cell motility have been more clearly delineated. These new findings, coupled with the advent of high-throughput screening technology have led to the discovery of many compounds that can target specific mutations and/or influence deregulated transcription. In this review, we intend to provide a concise overview of genetic and molecular events that drive cellular processes in lymphomas and represent potential therapeutic targets. Additionally, we briefly discuss the prognostic significance of select biological markers.

A phase II study to evaluate lenalidomide in combination with metronomic-dose cyclophosphamide in patients with heavily pretreated classical Hodgkin lymphoma

BACKGROUND

Relapsed or refractory (R/R) classical Hodgkin lymphoma (cHL) after autologous stem cell transplantation (ASCT) remains a challenge. For these patients treatments with different mechanisms of action rather than classical chemotherapy are needed.

PATIENTS AND METHODS

Patients with R/R cHL after ASCT were recruited in a phase II trial (EUDRA CT: 2009-016588-12). Lenalidomide was administered at 20 mg/day for 21 days and cyclophosphamide at 50 mg/day for 28 days (cycles every 28 days). Dose escalation for lenalidomide was permitted. In 2009 we considered that this treatment would be promising if response rate were over 60% and a Simon two-stage binomial design was used to calculate the sample size. A total of 46 patients were planned but the trial would be stopped if less than seven responses after four cycles were obtained in the first 16 patients.

RESULTS

The trial was closed early because only five responses were observed after four cycles in the first 16 patients included. Median age was 34 years (18-77). The median number of previous lines was five (2-6). At inclusion, 10 patients were primary refractory and 11 refractory to the last therapy. A total of 110 cycles were administered, with grade≥3 toxicity in 43 cycles (39%). One non-neutropenic patient developed septic shock resulting in death. An ORR of 38% (1 CR and 5 PR) was observed and a total of 10 patients (62%) achieved clinical benefit. Median progression free survival and overall survival were seven and 19 months, respectively. With a median follow-up of 19 months (3-38+), three-year progression-free and overall survival were 6% and 31%, respectively.

CONCLUSION

The optimistic assumptions of this trial led to an early closure. However, the promising clinical benefit observed with the oral combination of lenalidomide and metronomic cyclophosphamide may justify its use for outpatient palliative treatment.

Antibodies and antibody-drug conjugates in the treatment of Hodgkin lymphoma

Hodgkin lymphoma (HL) is a B cell-derived lymphoid malignancy most often affecting young adults. More than 80% of HL patients achieve long-term remission after appropriate first-line treatment consisting of multiagent chemotherapy and/or radiotherapy (RT). In addition, approximately 50% of patients with disease recurrence remain relapse-free after salvage therapy with high-dose chemotherapy followed by autologous stem cell transplantation (ASCT). However, patients with multiple relapses are mostly in a palliative situation, and novel drugs for this patient group are needed. Furthermore, novel less toxic but equally effective first-line and second-line approaches are required as therapy-related late sequelae represent a relevant cause of morbidity and mortality in HL survivors. Several antibodies and antibody-drug conjugates (ADC) targeting CD30 and CD20 have recently been evaluated in HL. Excellent response rates in heavily pretreated patients were observed with the ADC brentuximab vedotin directed against CD30. Thus, ongoing trials investigate brentuximab vedotin in different additional indications. One example is the first-line treatment of advanced HL where the drug is currently being evaluated in combination with variants of the first-line protocols ABVD (adriamycin, bleomycin, vinblastine, dacarbazine) and escalated BEACOPP (bleomycin, etoposide, adriamycin, cyclophosphamide, vincristine, procarbazine, prednisone). Anti-CD20 antibodies given either as single agent or in combination with conventional chemotherapy have also been investigated and still undergo investigation in prospective studies including HL patients. This article reviews the available data on treatment approaches including antibodies and ADC in HL patients.

An update on emerging drugs for Hodgkin lymphoma

INTRODUCTION

Most patients with Hodgkin lymphoma (HL) are cured with modern combined modality first-line treatments. Even ~ 50% of patients with relapsed/refractory HL can be cured with high-dose chemotherapy (HDCT) and autologous stem cell transplantation. However, chemotherapy and radiotherapy cause significant acute and long-term side effects and patients relapsing after HDCT have a dismal prognosis. New drugs are therefore needed to reduce the toxicity of first-line treatments and to increase the efficacy of relapse treatments. Moreover, new drugs are needed for the treatment of older patients with HL because results with current treatments are disappointing.

AREAS COVERED

This article discusses promising new drugs for the treatment of classical HL that have been evaluated in the last years. There is a focus on the antibody drug conjugate brentuximab vedotin and its potential for the future treatment of HL. Moreover, data on the histone deacetylase inhibitors panobinostat and mocetinostat, the mammalian target of rapamycin inhibitor everolimus, the Janus kinase 2 inhibitor SB1518 and the immunomodulatory agent lenalidomide are summarized.

EXPERT OPINION

Besides improving the prognosis of relapsed patients, new drugs should be used to replace the most toxic compounds in first-line therapy to reduce acute and long-term toxicities of the treatment.

Trial Watch: Lenalidomide-based immunochemotherapy

Lenalidomide is a synthetic derivative of thalidomide currently approved by the US Food and Drug Administration for use in patients affected by multiple myeloma (in combination with dexamethasone) and low or intermediate-1 risk myelodysplastic syndromes that harbor 5q cytogenetic abnormalities. For illustrative purposes, the mechanism of action of lenalidomide can be subdivided into a cancer cell-intrinsic, a stromal, and an immunological component. Indeed, lenalidomide not only exerts direct cell cycle-arresting and pro-apoptotic effects on malignant cells, but also interferes with their physical and functional interaction with the tumor microenvironment and mediates a robust, pleiotropic immunostimulatory activity. In particular, lenalidomide has been shown to stimulate the cytotoxic functions of T lymphocytes and natural killer cells, to limit the immunosuppressive impact of regulatory T cells, and to modulate the secretion of a wide range of cytokines, including tumor necrosis factor α, interferon γ as well as interleukin (IL)-6, IL-10, and IL-12. Throughout the last decade, the antineoplastic and immunostimulatory potential of lenalidomide has been investigated in patients affected by a wide variety of hematological and solid malignancies. Here, we discuss the results of these studies and review the status of clinical trials currently assessing the safety and efficacy of this potent immunomodulatory drug in oncological indications.

New drugs and targeted treatments in Hodgkin's lymphoma

New drugs are being developed in recent years that may change the handling of relapsed and refractory Hodgkin's lymphoma patients. Brentuximab vedotin treatment has already been approved by the FDA; and other drugs are promising, such as histone deacetylase inhibitors, bendamustine, lenalidomide and m-TOR inhibitors.

Hodgkin lymphoma

Hodgkin lymphoma (HL), a B cell-derived cancer, is one of the most common lymphomas. In HL, the tumor cells--Hodgkin and Reed-Sternberg (HRS) cells--are usually very rare in the tissue. Although HRS cells are derived from mature B cells, they have largely lost their B cell phenotype and show a very unusual co-expression of markers of various hematopoietic cell types. HRS cells show deregulated activation of multiple signaling pathways and transcription factors. The activation of these pathways and factors is partly mediated through interactions of HRS cells with various other types of cells in the microenvironment, but also through genetic lesions. The transforming events involved in the pathogenesis of HL are only partly understood, but mutations affecting the NF-κB and JAK/STAT pathways are frequent. The dependency of HRS cells on microenvironmental interactions and deregulated signaling pathways may offer novel strategies for targeted therapies.

Hodgkin's lymphoma in adults

Management of Hodgkin's lymphoma continues to develop. Outcomes for patients with favourable-risk, early-stage disease are excellent, and serial reductions in intensity of treatment have been made to retain the excellent prognosis while reducing the late effects of treatment. Prognosis is also very good in advanced-stage disease but the rate of relapse is higher than in early-stage disease, and the optimum first-line treatment is unclear. Workers are investigating the role of functional imaging to assess whether treatment can be tailored according to response, with the most intensive therapies reserved for patients predicted to have poor outcomes. In this Seminar we critically appraise the management of Hodgkin's lymphoma in early-stage disease, advanced-stage disease, and at relapse, with a focus on late effects of treatment.

Role of immune escape mechanisms in Hodgkin's lymphoma development and progression: a whole new world with therapeutic implications

Hodgkin's lymphoma represents one of the most frequent lymphoproliferative syndromes, especially in young population. Although HL is considered one of the most curable tumors, a sizeable fraction of patients recur after successful upfront treatment or, less commonly, are primarily resistant. This work tries to summarize the data on clinical, histological, pathological, and biological factors in HL, with special emphasis on the improvement of prognosis and their impact on therapeutical strategies. The recent advances in our understanding of HL biology and immunology show that infiltrated immune cells and cytokines in the tumoral microenvironment may play different functions that seem tightly related with clinical outcomes. Strategies aimed at interfering with the crosstalk between tumoral Reed-Sternberg cells and their cellular partners have been taken into account in the development of new immunotherapies that target different cell components of HL microenvironment. This new knowledge will probably translate into a change in the antineoplastic treatments in HL in the next future and hopefully will increase the curability rates of this disease.

Expression of COX-2 on Reed-Sternberg cells is an independent unfavorable prognostic factor in Hodgkin lymphoma treated with ABVD

Cyclooxygenase 2 (COX-2) is an inflammatory enzyme involved in the pathogenesis and prognosis of several malignancies. In the present study, we investigated the prognostic value of COX-2 expression in a large (N = 242), uniformly treated Hodgkin lymphoma (HL) population from the Spanish Network of HL using tissue microarrays. Univariate and multivariate analysis was done, including comparing the most recognized clinical variables: the early- and advanced-stage subgroups. COX-2 was expressed on Reed-Sternberg cells in 37% of patients. There were no differences in the distribution of clinical variables according to COX-2 expression. With a median follow-up time of 58 months, PFS at 5 years was 60% and 79% for COX-2+ and COX-2− patients, respectively (P = .003). The overall survival was 73% and 91%, respectively (P < .001). The major impact on prognosis was observed in the early AA stage (I-II) group. In fact, in these low-risk groups the expression of COX-2 defined a group with significantly worse progression-free and overall survival. In conclusion, COX-2 was expressed on Reed-Sternberg cells in one-third of HL patients and was a major independent, unfavorable prognostic factor in early-stage HL. We conclude that COX-2 may be a major prognostic variable in HL and a potential therapeutic target.

Advances in the treatment of relapsed or refractory Hodgkin's lymphoma

Hodgkin's lymphoma (HL) is diagnosed in 20,000 men and women annually in North America and Europe. Despite treatment advancements for HL resulting in an overall survival rate of 80%, patients with advanced stage disease continue to have suboptimal outcomes, with relapse rates of 30%-40%. An additional 10%-15% of patients present with primary refractory disease. For patients who relapse after initial treatment, salvage chemotherapy followed by autologous stem cell transplant in those with chemotherapy-sensitive disease is the standard of care. Patients who relapse after second-line therapy have a median survival time in the range of 6-36 months, and the optimal management of these patients remains unclear. Unfortunately, there have been no new agents approved for relapsed HL treatment since the 1970s. Consequently, clinical decision making in this population is difficult. Recently however, several agents have emerged that have shown clinical promise in this poor-risk population. This review discusses the management of these patients and also discusses several newer agents showing clinical promise in the treatment of HL.

Current status of autologous stem cell transplantation in relapsed and refractory Hodgkin's lymphoma

Despite the relatively high long-term disease-free survival (DFS) rate for patients with Hodgkin lymphoma (HL) with modern combination chemotherapy or combined modality regimens, ∼20% of patients die from progressive or relapsed disease. The standard treatment for relapsed and primary refractory HL is salvage chemotherapy followed by high-dose chemotherapy and autologous stem cell transplantation (ASCT), which has shown a 5-year progression-free survival rate of ∼50%-60%. Recent developments in a number of diagnostic and therapeutic modalities have begun to improve these results. Functional imaging, refinement of clinical prognostic factors, and development of novel biomarkers have improved the predictive algorithms, allowing better patient selection and timing for ASCT. In addition, these algorithms have begun to identify a group of patients who are candidates for more aggressive treatment beyond standard ASCT. Novel salvage regimens may potentially improve the rate of complete remission prior to ASCT, and the use of maintenance therapy after ASCT has become a subject of current investigation. We present a summary of developments in each of these areas.

Clinical development of panobinostat in classical Hodgkin's lymphoma

Deacetylase (DAC) inhibitors are promising new anticancer drugs that have complex mechanisms of action, including induction of cell-cycle arrest and apoptosis, inhibition of angiogenesis and induction of a favorable anti-tumor immune response. Panobinostat, a potent inhibitor of DAC 1-11 enzymatic activity, has demonstrated a significant in vitro antiproliferative activity against classical Hodgkin's lymphoma (cHL) cell lines in addition to a promising clinical activity in early Phase I studies in patients with relapsed cHL. In a recently completed large Phase II study in patients with relapsed cHL, panobinostat reduced tumor measurements in 74% of patients, including 23% partial and 4% complete remissions. In this article, we review the status of panobinostat drug development and compare its activity to those of other DAC inhibitors in patients with relapsed cHL. Future investigations should focus on designing rational combination regimens and identifying predictive markers that will assist in selecting patients who are likely to benefit from this novel therapy.

A phase 2 multicenter study of lenalidomide in relapsed or refractory classical Hodgkin lymphoma

Relapsed or refractory (rel/ref) classical Hodgkin lymphoma (cHL) remains a clinical challenge, with limited effective treatment options available after stem cell transplantation. In a multicenter phase 2 study, the efficacy of lenalidomide in rel/ref cHL patients was evaluated at a dose of 25 mg/d on days 1-21 of a 28-day cycle. Patients remained on lenalidomide until disease progression or an unacceptable adverse event (AE) occurred. Thirty-eight cHL patients were enrolled with a median of 4 (range, 2-9) prior therapies; 87% had undergone prior stem cell transplantation and 55% of patients did not respond to their last prior therapy. Of 36 evaluable patients, responses were 1 complete remission (CR), 6 partial remissions (PRs), and 5 patients with stable disease (SD) for ≥ 6 months resulting in an International Working Committee (IWC) objective overall response rate (ORR) of 19% and a cytostatic ORR of 33%. Decreased chemokine (CCL17 and CCL22) plasma levels at 2 weeks were associated with a subsequent response. The treatment was well tolerated, and the most common grade 3/4 AEs were neutropenia (47%), anemia (29%), and thrombocytopenia (18%). Four patients discontinued lenalidomide because of rash, elevated transaminases/bilirubin, and cytopenias. We provide preliminary evidence of lenalidomide's activity in patients with rel/ref cHL, and therefore exploration of lenalidomide in combination with other active agents is warranted. This trial is registered at www.ClinicalTrials.gov as NCT00540007.

Immunomodulating antibodies and drugs for the treatment of hematological malignancies

The aim of cancer immunotherapy is to induce immune cells to kill tumor and promote immunological memory that protects against tumor recurrence. Most current immunotherapies, such as monoclonal antibodies (mAb), target the tumor cells directly. Advances in our understanding of the immune system such as the role of co-stimulatory and co-inhibitory receptors, and the advent of new immunomodulatory agents provide new opportunities to target the immune system and enhance anti-tumor immune responses. These promising agents include immunomodulating mAbs, Toll-like receptor agonists, IMiDs, and cytokines. In this review, we discuss the current results of immunomodulating agents in the treatment of hematological malignancies and propose applications that include targeting of the innate and adaptive immune systems as well as combinations with tumor-specific mAbs.

The Management of Classical Hodgkin's Lymphoma: Past, Present, and Future

The management of classical Hodgkin's lymphoma (CHL) is a success story of modern multi-agent haemato-oncology. Prior to the middle of the twentieth century CHL was fatal in the majority of cases. Introduction of single agent radiotherapy (RT) demonstrated for the first time that these patients could be cured. Developments in chemotherapy including the mechlorethamine, vincristine, procarbazine and prednisolone (MOPP) and Adriamycin, bleomycin, vinblastine and dacarbazine (ABVD) regimens have resulted in cure rates of over 80%. Even in relapse, CHL patients can be salvaged with high dose chemotherapy and autologous haematopoietic stem cell transplantation (ASCT). Challenges remain, however, in finding new strategies to manage the small number of patients who continue to relapse or progress. In addition, the young age of many Hodgkin's patients forces difficult decisions in balancing the benefit of early disease control against the survival disadvantage of late toxicity. In this article we aim to summarise past trials, define the current standard of care and appraise future developments in the management of CHL.

Brentuximab vedotin for the treatment of CD30+ lymphomas

Brentuximab vedotin is a novel antibody–drug conjugate consisting of the anti-CD30 antibody cAC10 chemically conjugated to monomethylauristatin E, a potent antimicrotubule agent. Preliminary response rates of 75% in relapsed/refractory Hodgkin’s lymphoma and 87% in relapsed/refractory systemic anaplastic large-cell lymphoma were recently reported in large Phase II trials. Brentuximab vedotin is well tolerated with manageable side effects including peripheral sensory neuropathy. This antibody–drug conjugate is currently under investigation in numerous clinical trials, including in combination with front-line chemotherapy for high-risk Hodgkin’s lymphoma and in a placebo-controlled, Phase III trial for patients with Hodgkin’s lymphoma at high risk for residual disease following autologous stem cell transplant. The impressive response rates and limited toxicity of brentuximab vedotin are very promising for relapsed/refractory patients with few treatment options. In addition, the possibilities for incorporation into front-line therapies for both Hodgkin’s lymphoma and systemic anaplastic large-cell lymphoma are intriguing.

Recent Advances in the Pathobiology of Hodgkin's Lymphoma: Potential Impact on Diagnostic, Predictive, and Therapeutic Strategies

From its first description by Thomas Hodgkin in 1832, Hodgkin's disease, now called Hodgkin's lymphoma, has continued to be a fascinating neoplasm even to this day. In this review, historical aspects, epidemiology, diagnosis, tumor biology, new observations related to host-microenvironment interactions, gene copy number variation, and gene expression profiling in this complex neoplasm are described, with an exploration of chemoresistance mechanisms and potential novel therapies for refractory disease.