Prospective subgroup analyses of the randomized MCL‐002 (SPRINT) study: lenalidomide versus investigator's choice in relapsed or refractory mantle cell lymphoma

In the mantle cell lymphoma (MCL)‐002 study, lenalidomide demonstrated significantly improved median progression‐free survival (PFS) compared with investigator's choice (IC) in patients with relapsed/refractory MCL. Here we present the long‐term follow‐up data and results of preplanned subgroup exploratory analyses from MCL‐002 to evaluate the potential impact of demographic factors, baseline clinical characteristics and prior therapies on PFS. In MCL‐002, patients with relapsed/refractory MCL were randomized 2:1 to receive lenalidomide (25 mg/day orally on days 1–21; 28‐day cycles) or single‐agent IC therapy (rituximab, gemcitabine, fludarabine, chlorambucil or cytarabine). The intent‐to‐treat population comprised 254 patients (lenalidomide, n = 170; IC, n = 84). Subgroup analyses of PFS favoured lenalidomide over IC across most characteristics, including risk factors, such as high MCL International Prognostic Index score, age ≥65 years, high lactate dehydrogenase (LDH), stage III/IV disease, high tumour burden, and refractoriness to last prior therapy. By multivariate Cox regression analysis, factors associated with significantly longer PFS (other than lenalidomide treatment) included normal LDH levels (P < 0·001), nonbulky disease (P = 0·045), <3 prior antilymphoma treatments (P = 0·005), and ≥6 months since last prior treatment (P = 0·032). Overall, lenalidomide improved PFS versus single‐agent IC therapy in patients with relapsed/refractory MCL, irrespective of many demographic factors, disease characteristics and prior treatment history.     

Lenalidomide oral monotherapy produces a high response rate in patients with relapsed or refractory mantle cell lymphoma

Mantle cell lymphoma (MCL) is an aggressive non-Hodgkin lymphoma with a poor prognosis following first relapse. We present a subgroup analysis of an open-label phase II trial investigating the efficacy and safety of lenalidomide in patients with relapsed or refractory MCL. Oral lenalidomide 25 mg was self-administered once daily on days 1–21 every 28 d for up to 52 weeks, according to tolerability or until disease progression. The primary endpoint was overall response rate (ORR) and secondary endpoints were duration of response, progression-free survival (PFS) and safety. Among 15 patients with MCL with a median disease duration of 5·1 years and a median of four prior treatments, the ORR was 53%. Three patients (20%) had a complete response and 5 (33%) had a partial response. The median duration of response was 13·7 months and median PFS was 5·6 months. Four of five patients who relapsed after transplantation and two of five patients who previously received bortezomib responded to lenalidomide. The most common grade 4 adverse event was thrombocytopenia (13%) and the most common grade 3 adverse events were neutropenia (40%), leucopenia (27%) and thrombocytopenia (20%). In conclusion, oral lenalidomide monotherapy is well tolerated and active in relapsed or refractory MCL.     

Ki‐67 expression as a prognostic factor in diffuse large B‐cell lymphoma patients treated with rituximab plus CHOP

Background: Assessment of tumor cell proliferation based on Ki‐67 expression yielded conflicting prognostic predictions of patients with diffuse large B‐cell lymphoma (DLBCL). The introduction of rituximab to the DLBCL treatment regime has led to alterations in the significance of previous prognostic factors. Methods: We analyzed Ki‐67 expression and its correlation with prognosis in 144 patients with DLBCL treated with rituximab plus CHOP (R‐CHOP) between July 2003 and January 2008. Results: The complete response (CR) rates following R‐CHOP administration were not significantly different, based on Ki‐67 expression status (P = 0.104). However, higher rates of relapse were observed in the high Ki‐67 expression group (Ki‐67 ≥ 85%, n = 46) with 25.0%, compared to 10.0% in the low Ki‐67 expression group (Ki‐67 < 85%, n = 88) (P = 0.040). The 2‐yr event‐free survival (EFS) rates were 44.3% and 74.1% in the high and low Ki‐67 expression groups, respectively (P = 0.011). The 2‐yr overall survival (OS) rate was 66.4% in the high Ki‐67 expression group and 82.2% in the low Ki‐67 expression group (P = 0.016). In multivariate analysis, Ki‐67 expression was a significant prognostic factor for EFS [hazard ratio (HR) = 2.909; 95% confidence interval (CI) 1.261–6.708; P = 0.012]. Ki‐67 was associated with OS but with borderline significance (HR = 2.876; 95% CI, 0.972–8.508; P = 0.056). Conclusion: Elevated Ki‐67 expression seems to be associated with higher relapse after CR and inferior EFS in patients with DLBCL treated with R‐CHOP.     

Single‐agent lenalidomide in relapsed/refractory mantle cell lymphoma: results from a UK phase II study suggest activity and possible gender differences

We present data from a phase II study investigating a novel treatment strategy for relapsed/refractory mantle cell lymphoma (MCL). Twenty‐six patients received lenalidomide 25 mg/d (days 1–21 of a 28‐d cycle) for up to 6 cycles followed by low‐dose maintenance lenalidomide (15 mg) in responding patients. Eight patients achieved complete or partial response to give an overall response rate of 31% with median response duration of 22·2 months [95% confidence interval (CI) 0·0–53·6] and median progression‐free survival (PFS) of 3·9 months (95% CI 0·0–11·1). An additional six patients (23%) achieved stable disease. Eleven patients received maintenance with median PFS of 14·6 months (95% CI 7·3–21·9). Correlative studies showed that peripheral T and Natural Killer (NK) cells increased in responding patients by 40–60% over the first 6 cycles with an initial dip in NK cells suggestive of tumour infiltration. Peripheral regulatory T cells were increased in MCL patients (P = 0·001) and expanded further following lenalidomide. Sequential plasma analysis showed increased IL12 p40 and IL7 alongside decreased MMP9, IL10, and adiponectin. Finally, a significant correlation (P = 0·02) between gender and response suggested that female MCL patients were more sensitive to lenalidomide than males. In summary, we confirm the activity, safety and immunomodulatory properties of lenalidomide in MCL and highlight its potential as a low‐dose maintenance agent.     

Activity of lenalidomide in mantle cell lymphoma can be explained by NK cell‐mediated cytotoxicity

Lenalidomide is an immunomodulatory agent that has demonstrated clinical benefit for patients with relapsed or refractory mantle cell lymphoma (MCL); however, despite this observed clinical activity, the mechanism of action (MOA) of lenalidomide has not been characterized in this setting. We investigated the MOA of lenalidomide in clinical samples from patients enrolled in the CC‐5013‐MCL‐002 trial (NCT00875667) comparing single‐agent lenalidomide versus investigator's choice single‐agent therapy and validated our findings in pre‐clinical models of MCL. Our results revealed a significant increase in natural killer (NK) cells relative to total lymphocytes in lenalidomide responders compared to non‐responders that was associated with a trend towards prolonged progression‐free survival and overall survival. Clinical response to lenalidomide was independent of baseline tumour microenvironment expression of its molecular target, cereblon, as well as genetic mutations reported to impact clinical response to the Bruton tyrosine kinase inhibitor ibrutinib. Preclinical experiments revealed lenalidomide enhanced NK cell‐mediated cytotoxicity against MCL cells via increased lytic immunological synapse formation and secretion of granzyme B. In contrast, lenalidomide exhibited minimal direct cytotoxic effects against MCL cells. Taken together, these data provide the first insight into the clinical activity of lenalidomide against MCL, revealing a predominately immune‐mediated MOA.     

Salvage treatment with lenalidomide and dexamethasone in relapsed/refractory mantle cell lymphoma: clinical results and effects on microenvironment and neo-angiogenic biomarkers

Background

Preclinical studies have highlighted the activity of lenalidomide in mantle cell lymphoma and its anti-proliferative synergy with dexamethasone.

Design and Methods

In this prospective, multicenter, phase II study, patients with relapsed/refractory mantle cell lymphoma who were not eligible for, or had relapsed after, intensive treatments received lenalidomide 25 mg/day (days 1–21 of each 28-day cycle) and dexamethasone (40 mg/day on days 1, 8, 15, and 22) for up to 12 months.

Results

The primary end-points, overall and complete response rates, were achieved by 17 of 33 (52%; 95% confidence interval [CI], 35–68%) and 8 of 33 patients (24%; 95% CI, 13–41%), respectively, by the end of treatment. Fifteen patients (45%) discontinued treatment prematurely, 13 due to lack of response. The median progression-free and overall survival were 12 months (95% CI, 5–19 months) and 20 months (95% CI, 12 months to not estimable), respectively. Treatment resulted in a significant increase in microvessel density (P=0.033) and non-significant increases in macrophage and natural killer cell counts, while serum levels of neoangiogenic factors did not change significantly. Grade 3/4 adverse events were neutropenia (53%), leukopenia (25%), thrombocytopenia (22%), infections (12%), and febrile neutropenia (12%).

Conclusions

These results confirm a favorable safety and activity profile of lenalidomide in relapsed/refractory mantle cell lymphoma. The contribution of dexamethasone in achieving these results is unclear because of its possible detrimental effect on the immune activation generated by lenalidomide and a higher risk of developing infectious complications. (clinicaltrials.gov identifier: NCT00786851).     

Therapy refractory angioimmunoblastic T‐cell lymphoma in complete remission with lenalidomide

The prognosis of therapy refractory angioimmunoblastic lymphoma (AITL) is very poor. In this report we describe a patient with AITL refractory to 2 lines of chemotherapy. He was treated with lenalidomide 15 mg continuously and prednisone. After 2 yr follow‐up, the patient has no detectable disease. Lenalidomide was well tolerated without side‐effects. Lenalidomide even in lower dosed combined with steroids can induce complete responses in patients with refractory AITL.     

A multicentre phase II clinical experience with the novel aza-epothilone Ixabepilone (BMS247550) in patients with relapsed or refractory indolent non-Hodgkin lymphoma and mantle cell lymphoma

The epothilones represent a novel group of microtubule stabilization agents that appear to retain activity even in chemotherapy-resistant cell lines and animal models. Because of their ability to overcome chemotherapy resistance, we conducted a phase II study of Ixabepilone in patients with indolent non-Hodgkin lymphoma and mantle cell lymphoma (MCL). Ixabepilone was given at a dose of 25 mg/m(2) weekly for three of four consecutive weeks. Patients were required to have received < or =4 prior chemotherapy regimens, with an interval of at least one month since the last treatment, 3 months from prior rituximab, and 7 d from prior steroids, an absolute neutrophil count >1 x 10(9)/l and a platelet count >50 x 10(9)/l. Dose reductions were allowed. The overall response rate in assessable patients was 27% in this otherwise heavily treated population. One patient with chemotherapy-refractory follicular lymphoma attained a complete remission that lasted approximately 8 months. Three responses were also seen in refractory MCL and one in small lymphocytic lymphoma. The duration of response ranged from 2 to 8 months. Major toxicities included fatigue, myelosuppression and neuropathy. These data suggest that Ixabepilone has activity in chemotherapy-refractory lymphoma.     

Four‐year follow‐up of a single arm,phase II clinical trial of ibrutinib with rituximab (IR) in patients with relapsed/refractory mantle cell lymphoma (MCL)

Ibrutinib has shown significant activity in patients with relapsed or refractory mantle cell lymphoma (RR‐MCL). We report the long‐term outcome and safety profile of a single‐centre, single arm, open‐label, phase 2 study of RR‐MCL treated with IR. Overall, the median follow‐up time was 47 months (range 1–52 months), median duration on treatment was 16 months (range 1–53 months) and median number of treatment cycles was 17 (range 1–56). Twenty‐nine patients (58%) achieved complete remission and of these, 12 patients continue on study. Thirty‐eight patients discontinued treatment, 14 due to disease progression (2 transformed). Patients with blastoid morphology, high risk MCL International Prognostic Index score and high Ki67% had inferior survival. The commonest grade 1–2 toxicities were fatigue, diarrhoea, nausea, arthralgias and myalgias. None had long term toxicities. Median progression‐free survival was 43 months. Eighteen patients (36%) died (14 deaths were MCL‐related). The median overall survival has not been reached. Treatment with IR can provide durable remissions in a subset of patients with RR‐MCL, especially those with low Ki67%. The possible benefit of adding other therapies in combination with IR in RR‐MCL is under exploration.     

A multicenter phase II trial (SAKK 36/06) of single-agent everolimus (RAD001) in patients with relapsed or refractory mantle cell lymphoma

Background

Mantle cell lymphoma accounts for 6% of all B-cell lymphomas and is generally incurable. It is characterized by the translocation t(11;14) leading to cyclin D1 over-expression. Cyclin D1 is downstream of the mammalian target of rapamycin threonine kinase and can be effectively blocked by mammalian target of rapamycin inhibitors. We set out to examine the single agent activity of the orally available mammalian target of rapamycin inhibitor everolimus in a prospective, multicenter trial in patients with relapsed or refractory mantle cell lymphoma ({"type":"clinical-trial","attrs":{"text":"NCT00516412","term_id":"NCT00516412"}}NCT00516412).

Design and Methods

Eligible patients who had received a maximum of three prior lines of chemotherapy were given everolimus 10 mg for 28 days (one cycle) for a total of six cycles or until disease progression. The primary endpoint was the best objective response. Adverse reactions, progression-free survival and molecular response were secondary endpoints.

Results

Thirty-six patients (35 evaluable) were enrolled and treatment was generally well tolerated with Common Terminology Criteria grade ≥3 adverse events (>5%) including anemia (11%), thrombocytopenia (11%) and neutropenia (8%). The overall response rate was 20% (95% CI: 8–37%) with two complete remissions and five partial responses; 49% of the patients had stable disease. At a median follow-up of 6 months, the median progression-free survival was 5.5 months (95% CI: 2.8–8.2) overall and 17.0 (6.4–23.3) months for 18 patients who received six or more cycles of treatment. Three patients achieved a lasting complete molecular response, as assessed by polymerase chain reaction analysis of peripheral blood.

Conclusions

Everolimus as a single agent is well tolerated and has anti-lymphoma activity in relapsed or refractory mantle cell lymphoma. Further studies of everolimus in combination with chemotherapy or as a single agent for maintenance treatment are warranted. (Clinicaltrials.gov identifier: {"type":"clinical-trial","attrs":{"text":"NCT00516412","term_id":"NCT00516412"}}NCT00516412)     

Ten‐year follow‐up after intense chemoimmunotherapy with Rituximab‐HyperCVAD alternating with Rituximab‐high dose methotrexate/cytarabine (R‐MA) and without stem cell transplantation in patients with untreated aggressive mantle cell lymphoma

Mantle cell lymphoma (MCL) has a poor overall survival after treatment with conventional chemotherapy. Intense chemoimmunotherapy without consolidation stem cell transplantation is a potential therapeutic option. We report on a prospective Phase II study with rituximab in combination with fractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone (R‐Hyper‐CVAD) alternating with rituximab in combination with high‐dose methotrexate‐cytarabine (R‐MA) in untreated patients with diffuse and nodular MCL and their blastoid variants. Ninety‐seven patients were treated, of whom 97% responded and 87% achieved a complete remission. At 10 years of follow up (median 8 years), the median overall survival (OS) for all patients had not been reached and the median time to failure (TTF) for all patients was 4.6 years, without a plateau in the curves. For the group of patients aged 65 years or younger, the median OS had not been reached and the median TTF was 5.9 years. Multivariate analysis revealed pre‐treatment serum levels of β₂ microglobulin, International Prognostic Index (IPI) score and mantle cell IPI (MIPI) score, as predictive of both OS and TTF. We conclude that intense chemoimmunotherapy without stem cell transplantation is effective for untreated aggressive MCL.     

Histopathology, cell proliferation indices and clinical outcome in 304 patients with mantle cell lymphoma (MCL): a clinicopathological study from the European MCL Network

Mantle cell lymphoma (MCL) is a distinct lymphoma subtype with a particularly poor clinical outcome. The clinical relevance of the morphological characteristics of these tumours remains uncertain. The European MCL Network reviewed 304 cases of MCL to determine the prognostic significance of histopathological characteristics. Cytomorphological subtypes, growth pattern and markers of proliferation (mitotic and Ki-67 indices) were analysed. In addition to the known cytological subtypes, classical (87.5%), small cell (3.6%), pleomorphic (5.9%) and blastic (2.6%), we identified new pleomorphic subgroups with mixtures of cells (classical + pleomorphic type; 1.6%) or transitions (classical/pleomorphic type; 1.6%), which, however, did not differ significantly in overall survival time. Exactly 80.5% of cases displayed a diffuse growth pattern, whereas 19.5% of cases had a nodular growth pattern, which was associated with a slightly more favourable prognosis. A high proliferation rate (mitotic or Ki-67 indices) was associated with shorter overall survival. Cut-off levels were defined that allowed three subgroups with different proliferation rates to be discriminated, which showed significantly different clinical outcomes (P < 0.0001). Based on this large clinicopathological study of prospective clinical trials, multivariate analysis confirmed the central prognostic role of cell proliferation and its superiority to all other histomorphological and clinical criteria.     

A multicentre phase II study of vorinostat in patients with relapsed or refractory indolent B‐cell non‐Hodgkin lymphoma and mantle cell lymphoma

Although initial rituximab‐containing chemotherapies achieve high response rates, indolent B‐cell non‐Hodgkin lymphoma (B‐NHL), such as follicular lymphoma (FL), is still incurable. Therefore, new effective agents with novel mechanisms are anticipated. In this multicentre phase II study, patients with relapsed/refractory indolent B‐NHL and mantle cell lymphoma (MCL) received vorinostat 200 mg twice daily for 14 consecutive days in a 21‐d cycle until disease progression or unacceptable toxicity occurred. The primary endpoint was overall response rate (ORR) in FL patients and safety and tolerability in all patients. Secondary endpoints included progression‐free survival (PFS). Fifty‐six eligible patients were enrolled; 50 patients (39 with FL, seven with other B‐NHL, and four with MCL) were evaluable for ORR, and 40 patients had received rituximab‐containing prior chemotherapeutic regimens. For the 39 patients with FL, the ORR was 49% [95% confidence interval (CI): 32·4, 65·2] and the median PFS was 20 months (95% CI: 11·2, 29·7). Major toxicities were manageable grade 3/4 thrombocytopenia and neutropenia. Vorinostat offers sustained antitumour activity in patients with relapsed or refractory FL with an acceptable safety profile. Further investigation of vorinostat for clinical efficacy is warranted.     

Addition of lenalidomide to rituximab,ifosfamide, carboplatin,etoposide (RICER) in first‐relapse/primary refractory diffuse large B‐cell lymphoma

Relapsed/refractory diffuse large B‐cell lymphoma (DLBCL) is associated with a poor prognosis. Outcomes are particularly poor following immunochemotherapy failure or relapse within 12 months of induction. We conducted a Phase I/II trial of lenalidomide plus RICE (rituximab, ifosfamide, carboplatin, and etoposide) (RICER) as a salvage regimen for first‐relapse or primary refractory DLBCL. Dose‐escalated lenalidomide was combined with RICE every 14 d. After three cycles of RICER, patients with chemosensitive disease underwent stem cell collection and consolidation with BEAM [BCNU (carmustine), etoposide, cytarabine, melphalan] followed by autologous stem cell transplantation (autoSCT). Patients who recovered from autoSCT toxicities within 90 d initiated maintenance treatment with lenalidomide 25 mg daily for 21 d every 28 d for 12 months. No dose‐limiting or unexpected toxicities occurred with lenalidomide 25 mg plus RICE. Grade 3/4 haematological toxicities resolved appropriately, and planned dose density and dose intensity of RICER were preserved. No lenalidomide or RICE dose reductions were required in any of the three cycles. After two cycles of RICER, nine of 15 patients (60%) achieved a complete response, and two achieved a partial response (13%). Combining lenalidomide with RICE is feasible, and results in promising response rates (particularly complete response rates) in high‐risk DLBCL patients.     

Lenalidomide in combination with R‐ESHAP in patients with relapsed or refractory diffuse large B‐cell lymphoma: a phase 1b study from GELTAMO group

Diffuse large B‐cell lymphoma (DLBCL) patients failing rituximab‐containing therapy have a poor outcome with the current salvage regimens. We conducted a phase 1b trial to determine the maximum tolerated dose (MTD) of lenalidomide in combination with R‐ESHAP (rituximab, etoposide, cisplatin, cytarabine, methylprednisolone) (LR‐ESHAP) in patients with relapsed or refractory DLBCL. Efficacy data were collected as a secondary objective. Subjects received 3 cycles of lenalidomide at escalating doses (5, 10 or 15 mg) given on days 1–14 of every 21‐day cycle, in combination with R‐ESHAP. Responding patients received BEAM (carmustine, etoposide, cytarabine, melphalan) followed by autologous stem‐cell transplantation. Lenalidomide 10 mg/d was identified as the MTD because, in the 15 mg cohort, one patient experienced dose‐limiting toxicity (grade 3 angioedema) and two patients had mobilization failure. A total of 19 patients (3, 12 and 4 in the 5, 10 and 15 mg cohorts, respectively) were evaluable. All toxicities occurring during LR‐ESHAP cycles resolved appropriately and no grade 4–5 non‐haematological toxicities were observed. The complete remission and overall response rates were 47·4% and 78·9%, respectively. With a median follow‐up of 24·6 (17·4–38·2) months, the 2‐year progression‐free survival and overall survival were 44% and 63%, respectively. In conclusion, the LR‐ESHAP regimen is feasible and yields encouraging outcomes.