Post-infusion PD-1+CD8+CAR-T cells identify patients responsive to CD19-CAR-T therapy in non-Hodgkin's lymphoma.

Chimeric antigen receptor T cell therapy (CAR-T) has revolutionized treatment for relapsed/refractory (r/r) B-cell non-Hodgkin's lymphoma (NHL). Robust biomarkers and a complete understanding of CAR-T cell function in the post-infusion phase remain limited. Here we used a 37-color spectral flow cytometry panel to perform high dimensional single cell analysis of post-infusion samples in 26 patients treated with CD28 co-stimulatory domain containing commercial CAR-T (CD28-CAR-T) for NHL and focused on computationally gated CD8+ CAR-T cells. We found that the presence of post-infusion PD-1+ CD8+ CAR-T cells at the Day 14 timepoint highly correlated with the ability to achieve complete response (CR) by 6 months. Further analysis identified multiple subtypes of CD8+ PD-1+ CAR-T cells including PD-1+ TCF1+ stem-like CAR-T cells and PD-1+ TIM3+ effector-like CAR-T cells that correlated with improved clinical outcomes such as response and progression free survival. Additionally, we identified a subset of PD-1+ CD8+ CAR+ T cells with effector-like function that was increased in patients who achieved a CR and was associated with Grade 3 or higher immune effector cell-associated neurotoxicity syndrome. Here we identified robust biomarkers of response to CD28-CAR-T and highlight the importance of PD-1 positivity in CD8+ CAR-T cells post-infusion in achieving CR.

Patient-Reported Outcomes in Long-Term Survivors of Autologous Hematopoietic Cell Transplantation in Multiple Myeloma.

The overall survival in patients with transplantation-eligible multiple myeloma has tripled over the past 2 decades, leading to a growing population of myeloma survivors. However, there is a paucity of data on health-related quality of life (HRQoL), distress, and health behaviors in long-term myeloma survivors who are in stable remission after autologous hematopoietic cell transplantation (AHCT). In this cross-sectional study using data from 2 randomized controlled trials of survivorship care plans and internet-based self-management intervention in transplantation survivors, the primary objective was to measure HRQoL (using the Short Form-12, version 2.0 [SF-12 v2]), distress (using the Cancer- and Treatment-Related Distress [CTXD] instrument), and health behaviors of myeloma survivors in stable remission after AHCT. A total of 345 patients at a median of 4 years (range, 1.4 to 11 years) post-AHCT were included. The mean SF-12 v2 Physical Component Summary (PCS) score was 45.5 ± 10.5, and the mean Mental Component Summary (MCS) score was 51.3 ± 10.1, compared with US population norms of 50 ± 10 for both (P < .001 and P = .021 for PCS and MCS comparisons, respectively). Notably, neither reached the threshold for a minimal clinically important difference. Approximately one-third of the patients had clinically significant distress based on the CTXD total score, with distress reported by 53% of the patients in the Health Burden domain, by 46% in the Uncertainty domain, by 33% in the Finances domain, by 31% in the Family Strain domain, by 21% in the Identity domain, and by 15% in the Medical Demands domain. Preventive care guidelines were adhered to by 81% of the myeloma survivors; however, adherence to exercise and diet guidelines were relatively low, at 33% and 13%, respectively. Myeloma AHCT survivors in stable remission have no clinically meaningful worsening in physical functioning compared with the general population. Survivorship programs should address ongoing distress due to health burden, uncertainty, and finances in myeloma survivors, along with evidence-based targeted interventions for modifiable health behaviors, such as nutrition and exercise.

Health-Related Quality of Life Outcomes in Older Hematopoietic Cell Transplantation Survivors.

The use of hematopoietic cell transplantation (HCT) has been increasing in older patients. However, the levels if distress, psychosocial functioning, and health-related quality of life (HRQOL) among older HCT survivors remains largely unknown. In this secondary analysis using data from 2 randomized controlled trials, we analyzed baseline Cancer and Treatment Distress (CTXD) and Confidence In Survivorship Information (CSI) surveys of HCT survivors who were age ≥60 years at the time of transplantation and alive and disease-free ≥1 year post-autologous or -allogeneic HCT. We analyzed associations of these parameters with the Physical Component Summary (PCS) and Mental Component Summary (MCS) scores of the 12-Item Short Form Survey (SF-12) and a healthcare adherence (HCA) scale, after adjusting for transplantation and patient demographic factors. A total of 567 patients were included. The median patient age at HCT was 65 years, and 68% of the patients underwent autologous HCT. The median CTXD score was .7 (mild), and the greatest distress was reported in the "health burden" subscale. The median CSI score was 1.4 (moderate-high), with the lowest confidence reported in the "late effects" subscale. We found negative Spearman correlations between CTXD score and SF-12 PCS (P = -.59) and MCS (P = -.54) and positive Spearman correlations between CSI score and SF-12 PCS (P = .23) and MCS (P = .30). The median HCA scale score was high at .8. Male sex, autologous HCT, increased distress level, and worse CSI score were associated with lower use of preventive care. Older survivors experienced a low level of distress and moderate-high level of CSI at ≥1 year post-HCT. As lower distress and higher CSI were associated with improved HRQOL and optimized preventive HCA, CTXD/CSI measures can be used to individualize the care of older adult HCT survivors.

Health-Related Quality of Life in Young Adult Survivors of Hematopoietic Cell Transplantation.

Young adults (YA), age 18 to 39 years, are at a stage of life that may make them more vulnerable than older adults to impairments in health-related quality of life (HRQOL) during and after hematopoietic cell transplantation (HCT). Health self-efficacy (HSE), the belief that one can implement strategies to produce a desired health outcome, has been associated with health outcomes in oncology research. Little is known about HRQOL or HSE in YA HCT survivors compared with older HCT survivors. Given the age-specific psychosocial challenges facing YA HCT recipients and research on non-transplant YA cancer survivors, we hypothesized that YA survivors would have worse post-HCT HRQOL compared with older adults, and that among YA HCT survivors, higher levels of HSE would be associated with higher levels of HRQOL and lower levels of cancer-related distress. This was a cross-sectional secondary analysis of 2 combined baseline datasets from multicenter studies of HCT survivors approached for participation in clinical trials of survivorship interventions. Participants from 20 transplantation centers in the United States were at 1 to 10 years post-HCT and age ≥18 years at the time of study enrollment, had no evidence of disease relapse/progression or subsequent malignancies, and could read English adequately to consent for and complete assessments. Medical record and patient-reported data were obtained for demographics and HCT-related clinical factors and complications (eg, total body irradiation, chronic graft-versus-host disease [cGVHD]). Participants completed surveys on HRQOL, including the Short-Form [SF]-12, HSE, and Cancer and Treatment Distress (CTXD), which includes 6 subscales and reports an overall mean score. On the SF-12, both the Mental Component Score (MCS) and Physical Component Score (PCS) were calculated. Two cohorts were compared: YAs (age 18 to 39 years at transplantation) and older adults (age ≥40 years at transplantation). Multiple linear regression analyses identified factors associated with HSE, PCS, MCS, and CTXD in YAs. In this analysis of 979 survivors, compared with the older adults, the YA participants had lower median mental health scores (SF-12 MCS: 48.40 versus 50.23; P = .04) and higher cancer-related distress (CTXD: .96 versus .85; P = .04), but better physical health (SF-12 PCS: 48.99 versus 47.18; P = .049). Greater overall cancer-related distress was driven by higher levels of uncertainty, financial concern, and medical demand subscales for YAs compared with older adults. Young adults also had lower HSE (2.93 versus 3.08; P = .0004). In a multivariate model, HSE was strongly associated with age group (P = .0005) after adjusting for multiple other transplantation-related factors. Among YAs, HSE was associated with the SF-12 MCS and PCS and the CTXD, and HSE remained significant after adjusting for other transplantation-related factors. Overall, the YA HCT survivors had lower mental health, increased cancer-related distress, and lower levels of HSE compared with the older adults. Although the direction of these effects cannot be determined with these data, the strong association between HSE and HRQOL among YAs suggests that targeting interventions to improve HSE may have broad impact on health outcomes.

Selinexor Combined with Ibrutinib Demonstrates Tolerability and Safety in Advanced B-Cell Malignancies: A Phase I Study.

PURPOSE: Dual blockade of Bruton's tyrosine kinase with ibrutinib and selinexor has potential to deepen responses for patients with chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL). PATIENTS AND METHODS: In this phase I study (clinicaltrials.gov: NCT02303392), adult patients with CLL/NHL, relapsed/refractory to ≥1 prior therapy were enrolled. Patients received weekly oral selinexor and daily oral ibrutinib in 28-day cycles until progression or intolerance. Primary objective was to determine MTD. RESULTS: Included patients had CLL (n = 16) or NHL (n = 18; 9 Richter transformation, 6 diffuse large B-cell lymphoma, and 3 mantle cell lymphoma). Median prior therapies were 4 (range = 1-14) and 59% previously received ibrutinib. The established MTD was 40 mg of selinexor (days 1, 8, 15) and 420 mg daily ibrutinib. Common nonhematologic adverse events were fatigue (56%), nausea (53%), anorexia (41%), and diarrhea (41%) and were mostly low grade. Overall response rate was 32%. An additional 47% achieved stable disease (SD), some prolonged (up to 36 months). Median progression-free survival for patients with CLL and NHL was 8.9 [95% confidence interval (CI), 3.9-16.1] and 2.7 (95% CI, 0.7-5.4) months, respectively. For patients with CLL who did not receive prior ibrutinib, only 20% (1/5) progressed. Estimated 2-year overall survival was 73.7% (95% CI, 44.1-89.2) and 27.8% (95% CI, 10.1-48.9) for patients with CLL and NHL, respectively. CONCLUSIONS: The selinexor and ibrutinib combination has demonstrated tolerability in patients with relapsed/refractory CLL/NHL. Responses were durable. Notable responses were seen in patients with CLL with minimal prior therapy. Future study of this combination will focus on efforts to deepen remissions in patients with CLL receiving ibrutinib therapy.

Cutaneous manifestations of chimeric antigen receptor T-cell therapy: An introduction for dermatologists.

Chimeric antigen receptor T-cell therapy is an emerging immunotherapy with promising efficacy for the treatment of previously refractory or relapsed malignancies. As a personalized medicine approach, T cells are genetically engineered to express a receptor designed to bind a specific tumor antigen, leading to selective immune-mediated destruction of tumor cells. Due to the novelty of chimeric antigen receptor T-cell therapy, the safety profile continues to evolve with limited information currently available on cutaneous adverse events. Improved understanding of the spectrum of cutaneous adverse events may facilitate earlier recognition and appropriate management of these toxicities. To explore this knowledge gap, we discuss the available case reports and clinical trial results of cutaneous reactions associated with chimeric antigen receptor T-cell therapy.

Post-relapse survival in Waldenstrom macroglobulinemia patients experiencing therapy failure following autologous transplantation.

Waldenström macroglobulinemia (WM) is a rare B-cell lymphoproliferative malignancy. Autologous hematopoietic cell transplantation (auto-HCT) is considered in a subset of WM patients with relapsed disease. While registry data has shown a benefit for auto-HCT in relapsed WM, there is a paucity of data on outcomes of patients relapsing after auto-HCT. Eligibility criteria included adult patients with relapsed/refractory WM who underwent auto-HCT between 2007 and 2017. The primary endpoint was post-relapse overall survival (PR-OS). Secondary endpoints were to identify factors prognostic of PR-OS. Of the 48 patients with WM who underwent auto-HCT, 22 (46%) experienced relapse following auto-HCT. Median PR-OS of relapsed WM patients after auto-HCT (n = 22) was not reached (NR) (95% confidence interval [CI]: 17.5 months-NR). Among patients who relapsed <1 year versus ≥1 year from auto-HCT, the median PR-OS was 18.4 months (95%CI: 0.8-NR) months and NR (95%CI: 17.5-NR), respectively (p = 0.06). Of note, disease status at the time of transplant, CR/VGPR versus partial remission did not appear to impact PR-OS. The median PR-OS was significantly longer in patients who received ibrutinib in the post-transplant setting compared to those who did not (NR vs. 18.4 months, 95%CI: 9.1-NR, p = 0.02). On univariable analysis, the presence of complex karyotype (RR = 4.87, 95% CI = 1.22-19.53) and a higher number of prior lines of therapy (RR = 1.81, 95% CI = 1.23-2.67) were associated with a significantly higher risk of relapse. This is the only study to date that evaluated outcomes of WM patients who relapsed following auto-HCT and provides a benchmark for future trials evaluating survival following auto-HCT relapse.

Cytopenias After CD19 Chimeric Antigen Receptor T-Cells (CAR-T) Therapy for Diffuse Large B-Cell Lymphomas or Transformed Follicular Lymphoma: A Single Institution Experience.

INTRODUCTION: Patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) have poor outcomes. Treatment with CD19 chimeric antigen receptor (CAR-T) cells, tisagenlecleucel and axicabtagene ciloleucel, has been associated with improved outcomes. Cytopenias were observed in clinical trials with both products; however, little is known regarding the patterns and outcomes of these cytopenias. SUBJECTS AND METHODS: We reviewed DLBCL patients (n=32) receiving either product between January and September 2018 at our institution. RESULTS: Median duration of leukopenia, neutropenia, lymphopenia, anemia, and thrombocytopenia was 49, 9, 117.5, 125, and 95.5 days after CAR-T infusion, respectively. Filgrastim was used in 63% of patients, and 50% of patients received red cell or platelet transfusions. With the exception of neutropenia, increase in the duration of cytopenia of any lineage was associated with improvement in progression-free survival, and in overall survival in case of anemia. There was no association between the duration of cytopenias with either cytokine release syndrome or neurotoxicity. DISCUSSION: Our data suggest a correlation between cytopenias and survival outcomes after CD19 CAR-T therapy. If validated, cytopenia may be proven useful as a biomarker of response and survival after CAR-T therapy.

Safety of Axicabtagene Ciloleucel for the Treatment of Relapsed or Refractory Large B-Cell Lymphoma.

BACKGROUND: Diffuse large B-cell lymphoma is the most common type of non-Hodgkin lymphoma. Recent advances in immunotherapy have resulted in the development of chimeric antigen receptor-modified T-cell (CAR-T) therapy, such as axicabtagene ciloleucel (axi-cel). However, axi-cel administration is not without risks of toxicity. PATIENTS AND METHODS: This retrospective study of 37 patients with relapsed or refractory diffuse large B-cell lymphoma evaluated the incidence and severity of common and severe safety events after axi-cel treatment in a real-world setting. Ninety percent of patients had received 3 or more prior lines of therapy (median prior therapies 3, range 2-7) before receiving CAR-T therapy, and 32.4% had relapsed after prior stem-cell transplantation. RESULTS: All but one patient experienced cytokine release syndrome (CRS) of any grade (97.3%). Of those 36 patients, 83.3% experienced maximum CRS grade of 1 or 2, occurring after a median of 27 hours and persisting for a median of 6 days. Twenty-seven patients (73.0%) experienced neurotoxicity of any grade. Of those 27 patients, 96.3% experienced maximum neurotoxicity grade of 2 or higher, occurring after a median of 145 hours (6 days) and persisting for a median of 7 days. All 10 patients aged 65 or older had neurotoxicity of grade 2 or higher, compared to 59.3% (11/27) under age 65 (P = .02). Patients with baseline Eastern Cooperative Oncology Group performance status score of 2 were significantly more likely to have shorter time to neurotoxicity compared to patients with performance status of 0 (P = .01). CONCLUSION: With more real-life experience and data, we will be able to define and refine management of toxicities unique to CAR-T therapy.

A New Standard in Graft-versus-Host Disease Prophylaxis? An Introduction to Blood and Marrow Transplant Clinical Trials Network 1703.

Effective immunosuppressive regimens to prevent the development of graft-versus-host disease (GVHD) are essential to the success of allogeneic hematopoietic cell transplantation (HCT). After revolutionizing haploidentical transplantation, post-transplantation cyclophosphamide (PTCy) is now being evaluated for HCT performed from related and unrelated donors. In this setting, 2 recent randomized studies have demonstrated lower rates of GVHD and superior GVHD-free, relapse-free survival with PTCy compared with conventional GVHD prophylaxis. The Blood and Marrow Transplant Clinical Trials Network (BMT CTN) is currently conducting a large, randomized phase III, multicenter trial (BMT CTN 1703) comparing PTCy/tacrolimus/mycophenolate mofetil to tacrolimus/methotrexate as GVHD prophylaxis regimens in reduced-intensity allogeneic HCT. Here we review the ongoing study, highlight its importance to the field, and explore the possible implications of its results on clinical practice.

A Pilot Study of Lenalidomide Maintenance Therapy after Autologous Transplantation in Relapsed or Refractory Classical Hodgkin Lymphoma.

For patients with relapsed or refractory classical Hodgkin lymphoma (cHL), salvage chemotherapy followed by consolidation with autologous stem cell transplant (ASCT) remains the standard of care. Even with this aggressive treatment strategy, 5-year progression-free survival is ≤50%, and there remains interest in maintenance strategies to improve long-term disease-free survival. Lenalidomide is an immunomodulatory agent with demonstrated activity in multiple subtypes of lymphoma including cHL, and has also been shown to improve both progression-free and overall survival as maintenance therapy after ASCT in multiple myeloma. This multicenter study evaluated maintenance lenalidomide after ASCT for patients with cHL. Patients were enrolled 60 to 90 days post-transplant and received oral lenalidomide on days 1 to 28 of 28-day cycles for a maximum of 18 cycles. Lenalidomide was started at 15 mg daily and increased to maximum of 25 mg daily if tolerated. The primary objective of this study was to assess the feasibility of this regimen, with a goal <30% rate of discontinuation at or before cycle 12 for drug-related reasons. Twenty-seven patients were enrolled and 26 received at least 1 dose of lenalidomide. With a median follow-up of 51.3 months (range, 12.2 to 76.2 months), 23 of 26 patients were alive. Median event-free survival was 9.4 months and median progression-free survival had not been reached, with 17 of 26 patients (65.4%) remaining in remission at last follow-up. Excluding 4 patients who discontinued therapy for progression and 2 who discontinued due to noncompliance, the discontinuation rate at or before cycle 12 was 52%. Treatment was complicated by a high frequency of hematologic adverse events, with 15 patients (58%) experiencing grade 3 to 4 hematologic toxicity and 5 (19%) experiencing grade 4 hematologic toxicity. We conclude that the regimen of maintenance lenalidomide explored in this study is not feasible for patients with cHL immediately following ASCT. An alternative lenalidomide dose or schedule may be better tolerated following ASCT for patients with relapsed or refractory cHL.

Second cancer incidence in CLL patients receiving BTK inhibitors.

Chronic lymphocytic leukemia (CLL) is associated with perturbed immune function and increased risk for second primary malignancies (SPM). Ibrutinib and acalabrutinib (BTKi) are effective therapies for CLL resulting in partial restoration of immune function. The incidence of and risk factors for SPM in CLL patients receiving BTKi are not yet characterized. We retrospectively determined the incidence of SPM in CLL patients treated with ibrutinib or acalabrutinib at our institution between 2009 and 2017, assessed for association between baseline characteristics and SPM incidence, and compared the observed to expected cancer incidence among age, sex, and year matched controls without CLL. After a median of 44 months follow-up, 64/691 patients (9%) were diagnosed with SPM (excluding non-melanoma skin cancer [NMSC]). The 3-year cumulative incidence rate was 16% for NMSC and 7% for other SPM. On multivariable analysis, smoking was associated with increased SPM risk (HR 2.8 [95% CI: 1.6-4.8]) and higher baseline CD8 count was associated with lower SPM risk (HR 0.9 for 2-fold increase [95% CI: 0.8-0.9]). The observed over expected rate of SPM was 2.2 [95% CI: 1.7-2.9]. CLL patients treated with BTKi remain at increased risk for SPM, and secondary cancer detection is an important consideration in this population.

Fluoroquinolone Prophylaxis in Autologous Stem Cell Transplantation: Worthy of a Second Look.

Prophylaxis with fluoroquinolone (FQ) for patients undergoing autologous stem cell transplantation (ASCT) remains controversial. We performed a retrospective review of patients undergoing ASCT with and without bacterial prophylaxis to compare endpoints of interest. In accordance with institutional policy, patients undergoing ASCT for multiple myeloma routinely receive levofloxacin prophylaxis during their period of neutropenia, whereas patients undergoing the ASCT for lymphoma do not. We retrospectively examined patients with multiple myeloma (MM) or lymphoma undergoing ASCT between July 2015 and July 2018 for evidence of positive blood cultures. A total of 172 patients underwent ASCT for lymphoma and 343 underwent ASCT for MM. The 2 cohorts were similar in terms of baseline characteristics. Almost 20% (35 of 172) of the patients with lymphoma and 5.2% (18 of 342) of those with MM had a bloodstream infection (BSI). BSI occurred an average of 2 days earlier in patients with lymphoma compared with patients with MM (day +5 versus day +7; P = .0003). The 2 cohorts recovered absolute neutrophil count at the same time. Hospital length of stay was 2 days shorter for patients with MM (median, 20 days versus 18 days; P = .01). The majority of the organisms were gram-negative in both cohorts. Of the organisms commonly tested for FQ sensitivity, only 1 of 25 was resistant in the lymphoma cohort, compared with 7 of 9 in the MM cohort (P < .0001), with 4 being multidrug resistant. The odds of developing a BSI were 4.6 times greater in the lymphoma cohort compared with the MM cohort (95% confidence interval [CI], 2.52 to 8.40; P < .0001). In total, 23 of 172 patients with lymphoma (13.4%) and 28 of 342 patients with MM (8.2%) developed Clostridium difficile infection (odds ratio, 1.73; 95% CI, .96 to 3.11; P = .066). Two infection-related deaths occurred in the MM cohort. Our data indicate that FQ prophylaxis reduces the risk of BSI in patients undergoing ASCT but increases the incidence of resistant organisms. We recommend routine antimicrobial prophylaxis in patients undergoing ASCT to reduce the risk of BSI, along with a systematic and regular review of outcomes.

Tocilizumab as first-line therapy for steroid-refractory acute graft-versus-host-disease: analysis of a single-center experience.

Acute graft-versus-host-disease (aGVHD) is a complication after allogeneic stem cell transplant. After the failure of treatment with high dose corticosteroids, steroid-refractory aGVHD (SR aGVHD) is associated with high rates of mortality. Tocilizumab has evidence of activity in SR aGVHD. For patients ineligible for trials, the OSU James Comprehensive Cancer Center has been utilizing tocilizumab as first-line therapy for SR aGVHD. We retrospectively report on 15 patients who received tocilizumab. aGVHD grading and responses were based on consensus criteria. Median age at transplant was 49 years. Median time to tocilizumab administration was 9 days (range, 3-16). Six patients had complete responses (40%) with a resolution of aGVHD. From the last contact, median overall survival for responders was not yet reached vs. 31 days for non-responders (p = .0002). Patients with skin and/or GI aGVHD demonstrated the greatest benefit. Patients with liver aGVHD did not respond. Future studies are needed to evaluate tocilizumab prior to steroid failure.

How ibrutinib, a B-cell malignancy drug, became an FDA-approved second-line therapy for steroid-resistant chronic GVHD.

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is potentially curative for a number of hematologic conditions, both malignant and nonmalignant. However, its success can be limited by the development of acute and chronic graft-versus-host disease (GVHD). Chronic GVHD (cGVHD) is the most common long-term complication following allo-SCT, and patients who develop this condition have significantly higher morbidity and mortality and significantly lower quality of life than patients who do not. Until recently, there were no US Food and Drug Administration (FDA)-approved therapies for cGVHD treatment. In this review article, we describe how ibrutinib was identified as potential cGVHD therapy based on preclinical cGVHD models and clinical studies in B-cell malignancies and elucidation of its mechanisms of action in cGVHD. Results from a phase 2 clinical trial that was designed based on National Institutes of Health Criteria for the grading and staging of cGVHD culminated in the FDA-approval of ibrutinib as second line therapy of steroid-refractory or steroid-resistant cGVHD. Results of ibrutinib studies in phase 3 randomized studies, for cGVHD prophylaxis and as first -line testing along with steroids will be especially important in selecting the preferred indications for ibrutinib in patients at risk for or who have developed cGVHD.

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.