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)     

Phase 2 study of weekly bortezomib in mantle cell and follicular lymphoma

Twice-weekly bortezomib has proven activity in mantle cell (MCL) and indolent lymphomas. This study explored a weekly schedule of bortezomib in follicular lymphoma (FL) and MCL. Although weekly bortezomib was better tolerated, the overall response rate (ORR) was inferior (18% vs. 50%, P  = 0·02) with no complete remissions (CR) (compared with 18% CR for the twice-weekly schedule). Progression-free survival (PFS) was not different. The weekly schedule of bortezomib was less toxic, but yielded fewer and lower quality responses than twice-weekly bortezomib. Given the similar PFS, the weekly schedule may still be appropriate for some patients.     

Patients with chemotherapy-refractory mantle cell lymphoma experience high response rates and identical progression-free survivals compared with patients with relapsed disease following treatment with single agent bortezomib: results of a multicentre phase 2 clinical trial

The recent approval of bortezomib for the treatment of mantle cell lymphoma (MCL) by the US Food and Drug Administration is based on the results of the multicentre PINNACLE study with supportive data from a number of single and multicentre Phase 2 studies. This multicentre Phase 2 study enroled 40 patients with heavily pretreated MCL. The overall response rate (ORR) was 47%, including 5 complete remissions and 14 partial remissions. Overall, these remissions are relatively durable. The ORR in relapsed and refractory patients was 50% and 43% respectively ( P  = 0·74), while both populations of patients exhibited essentially similar progression-free survival (PFS; 5·6 months vs. 3·9 months, P  = 0·81). Responding patients experienced a PFS from bortezomib that was similar to their line of prior therapy (7·8 months vs. 8·4 months, respectively). The data showed similar responses in relapsed and refractory patients as well as remission durations similar to prior therapy, suggesting that there may be little cross-resistance with other conventional cytotoxic agents. Importantly, these data suggest that MCL patients with refractory or poorly responsive disease may still derive meaningful clinical benefit from treatment with bortezomib.     

A phase 2 study of two doses of bortezomib in relapsed or refractory myeloma

In a phase 2 open-label study of the novel proteasome inhibitor bortezomib, 54 patients with multiple myeloma who had relapsed after or were refractory to frontline therapy were randomized to receive intravenous 1.0 or 1.3 mg/m(2) bortezomib twice weekly for 2 weeks, every 3 weeks for a maximum of eight cycles. Dexamethasone was permitted in patients with progressive or stable disease after two or four cycles respectively. Responses were determined using modified European Group for Blood and Marrow Transplantation criteria. The complete response (CR) + partial response (PR) rate for bortezomib alone was 30% [90% confidence interval (CI), 15.7-47.1] and 38% (90% CI, 22.6-56.4) in the 1.0 mg/m(2) (8 of 27 patients) and 1.3 mg/m(2) (10 of 26 patients) groups respectively. The CR + PR rate for patients who received bortezomib alone or in combination with dexamethasone was 37% and 50% for the 1.0 and 1.3 mg/m(2) cohorts respectively. The most common grade 3 adverse events were thrombocytopenia (24%), neutropenia (17%), lymphopenia (11%) and peripheral neuropathy (9%). Grade 4 events were observed in 9% (five of 54 patients). Bortezomib alone or in combination with dexamethasone demonstrated therapeutic activity in patients with multiple myeloma who relapsed after frontline therapy.     

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).     

A phase 1, open‐label,dose‐escalation study of pralatrexate in combination with bortezomib in patients with relapsed/refractory multiple myeloma

Pralatrexate inhibits folic acid metabolism, and preclinical studies have shown that it is cytotoxic to multiple myeloma cells. This phase 1 study investigated the safety and efficacy of pralatrexate in combination with bortezomib in adults with relapsed or refractory multiple myeloma. A standard 3 + 3 design was used. Patients received intravenous pralatrexate at doses ranging from 10 to 30 mg/m² and intravenous bortezomib at a dose of 1·3 mg/m² on days 1, 8 and 15 of each 4‐week cycle. Eleven patients were enrolled and completed a median of two cycles. The maximum tolerated dose was 20 mg/m². Two patients experienced dose‐limiting toxicity of mucositis. The most frequent non‐haematological toxicities were fatigue (55%) and mucositis (45%). There were three serious adverse events in three patients: rash, sepsis and hypotension. One patient (9%) had a very good partial response, 1 (9%) had a partial response, 1 (9%) had minimal response and two (18%) had progressive disease. The median duration of response was 4 months, the median time to next treatment was 3·4 months and the median time to progression was 4 months. Pralatrexate, in combination with bortezomib, was generally safe and demonstrated modest activity in relapsed or refractory multiple myeloma. Clinicaltrials.gov identifier: NCT01114282.     

Addition of bortezomib to standard dose chop chemotherapy improves response and survival in relapsed mantle cell lymphoma

The proteasome inhibitor, bortezomib, potentially increases cell sensitivity to chemotherapy. This study was performed to determine the overall response rate (ORR), overall survival (OS), progression‐free survival (PFS) and toxicity of CHOP (cyclophosphamide, doxorubicin, vincristine and prednisolone) compared to CHOP + bortezomib chemotherapy in mantle cell lymphoma (MCL) patients at first relapse. Forty‐six patients were randomly assigned to standard dose CHOP ± bortezomib 1·6 mg/m² given on a 21‐d cycle for up to eight cycles of treatment. Median age was 71 years (CHOP arm) and 69 years (CHOP‐bortezomib arm). Median Eastern Cooperative Oncology Group performance status was 1 (CHOP) and 0 (CHOP‐bortezomib) with 65% and 52%, respectively, having a disease stage of IV. ORR was 47·8% (CHOP) and 82·6% (CHOP‐bortezomib). Complete response rate was 21·7% (CHOP) vs. 34·8% (CHOP‐bortezomib); partial response rate was 26·1% (CHOP) vs. 47·8% (CHOP‐bortezomib). Median OS was 11·8 months (CHOP) and 35·6 months (CHOP‐bortezomib) (P = 0·01, Hazard ratio [HR] 0·37 [95% confidence interval (CI) 0·16–0·83)] and there was a non‐significant improvement in PFS: 8·1 months (CHOP) and 16·5 months (CHOP‐bortezomib) [P = 0·12, HR 0·60 (95% CI 0·31–1·15)]. Severe (≥grade 3) sensory neuropathy was similar in both arms (4·3% CHOP vs. 6·5% CHOP‐bortezomib). We conclude that the addition of bortezomib to CHOP chemotherapy for relapsed MCL significantly improves outcome with a manageable increase in toxicity.     

Phase I trial of bortezomib in combination with rituximab‐HyperCVAD alternating with rituximab,methotrexate and cytarabine for untreated aggressive mantle cell lymphoma

Mantle cell lymphoma (MCL) outcomes have improved over the last two decades; however, late relapses occur. Bortezomib has shown single agent activity of 33% in relapsed MCL and has an additive/synergistic effect in vitro when combined with drugs currently used to treat MCL. We hypothesized that a combination of bortezomib with current intense non‐transplant chemoimmunotherapy might prevent late relapses. The toxicity of bortezomib when combined with methotrexate and cytarabine is unknown. Patients aged 18–79 years with untreated aggressive MCL were treated with R‐HyperCVAD (rituximab, cyclophosphamide, vincristine, doxorubicin, dexamethasone) alternating with rituximab‐methotrexate/cytarabine (R‐M/A). Bortezomib was added to the R‐Hyper‐CVAD combination as a fixed dose of 1·3 mg/m² IV on days 2 and 5 and was added to the R‐M/A regimen after rituximab, in increasing doses of 0·7, 1, and 1·3 mg/m² in cohorts of three patients. Twenty patients were assessed for toxicity of the regimen. The principal toxicity was haematological and did not differ from that observed with a similar regimen without the bortezomib. In particular, there was no pulmonary or neurological dose‐limiting toxicity, showing that bortezomib can be safely combined with R‐HyperCVAD and R‐M/A.     

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.     

Updated survival analyses after prolonged follow-up of the phase 2, multicenter CREST study of bortezomib in relapsed or refractory multiple myeloma

The Clinical Response and Efficacy Study of Bortezomib in the Treatment of Relapsing Multiple Myeloma (CREST) demonstrated substantial activity with two dose levels of bortezomib (1.0 and 1.3 mg/m(2)), alone or with dexamethasone, in relapsed or refractory multiple myeloma. We present updated survival analyses after prolonged follow-up (median >5 years). One- and 5-year survival rates were 82% and 32%, respectively, in the 1.0 mg/m(2) group (n = 28), and 81% and 45%, respectively, in the 1.3 mg/m(2) group (n = 26). Notable survival, response, and time-to-progression data suggest that a bortezomib starting dose of 1.3 mg/m(2) is preferred. If bortezomib dose reduction is required, the 1.0 mg/m(2) dose still offers patients a substantial survival benefit.     

Clinical activity of everolimus in relapsed/refractory marginal zone B‐cell lymphomas: results of a phase II study of the International Extranodal Lymphoma Study Group

The International Extranodal Lymphoma Study Group coordinated a phase II trial to evaluate the activity and safety of everolimus in marginal zone lymphomas (MZLs). Thirty patients with relapsed/refractory MZLs received everolimus for six cycles or until dose‐limiting toxicity or progression. Median age was 71 years (range, 51–88 years). Twenty patients had extranodal, six splenic, four nodal MZL. Twenty‐four patients had stage III–IV. Median number of prior therapies was two (range 1–5). Seventeen patients had early treatment discontinuation, in most cases due to toxicity. Median number of cycles was 4·5 (range, 1–16). Among the 24 assessable patients, the overall response rate (ORR) was 25% (95% confidence interval: 10–47). Grade 3–4 adverse events were neutropenia and thrombocytopenia (17% of patients, each), infections (17%), mucositis and odontogenic infections (13%) and lung toxicity (3%). The median response duration was 6·8 months (range, 1·4–11·1+). After a median follow‐up of 14·5 months, five deaths were reported: four deaths were due to lymphoma, one was due to toxicity. In an intent‐to‐treat analysis, the projected median progression‐free survival was 14 months. The moderate antitumour activity of everolimus in relapsed/refractory MZLs and the observed toxicity limit its therapeutical applicability in these indolent entities. Lower doses of the drug and, perhaps, different strategies including combination with additional agents need to be explored.     

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.     

The Bruton tyrosine kinase (BTK) inhibitor PCI‐32765 synergistically increases proteasome inhibitor activity in diffuse large‐B cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) cells sensitive or resistant to bortezomib

Interactions between the Bruton tyrosine kinase (BTK) inhibitor PCI‐32765 and the proteasome inhibitor (bortezomib) were examined in diffuse large‐B cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) cells, including those highly resistant to bortezomib. Co‐administration of PCI‐32765/bortezomib synergistically increased mitochondrial injury and apoptosis in germinal centre‐ or activated B‐cell‐like‐DLBCL cells and in MCL cells. These events were accompanied by marked AKT and nuclear factor (NF)‐κB (NFKB1) inactivation, down‐regulation of Mcl‐1 (MCL1), Bcl‐xL (BCL2L1), and XIAP, and enhanced DNA damage (e.g., γH2A.X formation) and endoplasmic reticulum (ER) stress. Similar interactions were observed in highly bortezomib‐resistant DLBCL and MCL cells, and in primary DLBCL cells. In contrast, PCI‐32765/bortezomib regimens displayed minimal toxicity toward normal CD34⁺ bone marrow cells. Transfection of DLBCL cells with a constitutively active AKT construct attenuated AKT inactivation and significantly diminished cell death, whereas expression of an NF‐κB “super‐repressor” (IκBα_ser34/36) increased both PCI‐32765 and bortezomib lethality. Moreover, cells in which the ER stress response was disabled by a dominant‐negative eIF2α construct were resistant to this regimen. Finally, combined exposure to PCI‐32765 and bortezomib resulted in more pronounced and sustained reactive oxygen species (ROS) generation, and ROS scavengers significantly diminished lethality. Given promising early clinical results for PCI‐32765 in DLBCL and MCL, a strategy combining BTK/proteasome inhibitor warrants attention in these malignancies.     

Elotuzumab in combination with thalidomide and low‐dose dexamethasone: a phase 2 single‐arm safety study in patients with relapsed/refractory multiple myeloma

Elotuzumab is an immunostimulatory, humanized immunoglobulin G1 monoclonal antibody that selectively targets and kills signalling lymphocytic activation molecule family member 7–expressing myeloma cells. We evaluated the safety and tolerability of elotuzumab 10 mg/kg combined with thalidomide 50–200 mg and dexamethasone 40 mg (with/without cyclophosphamide 50 mg) in patients with relapsed/refractory multiple myeloma (RRMM). The primary endpoint was the proportion of grade ≥3 non‐haematological adverse events (AEs); other endpoints included the number of dose reductions/discontinuations and efficacy. Forty patients were treated, who had a median of three previous therapies, including bortezomib (98%) and lenalidomide (73%). Grade ≥3 non‐haematological AEs were reported in 63% of patients, most commonly asthenia (35%) and peripheral oedema (25%). Six (15%) patients had an infusion reaction. Twenty‐six (65%) patients had ≥1 dose reduction/discontinuation due to an AE, none related to elotuzumab. Overall response rate was 38%; median progression‐free survival was 3·9 months. Median overall survival was 16·3 months and the 1‐year survival rate was 63%. Minimal incremental toxicity was observed with addition of elotuzumab to thalidomide/dexamethasone with or without cyclophosphamide, and efficacy data suggest clinical benefit in a highly pre‐treated population. Elotuzumab combined with thalidomide may provide an additional treatment option for patients with RRMM.     

The combination of bortezomib with chemotherapy to treat relapsed/refractory acute lymphoblastic leukaemia of childhood

Achieving complete remission (CR ) in childhood relapsed/refractory acute lymphoblastic leukaemia (ALL ) is a difficult task. Bortezomib, a proteasome inhibitor, has in vitro activity against ALL blasts. A phase I‐II trial, reported by the Therapeutic Advances in Childhood Leukaemia and Lymphoma (TACL ) consortium, demonstrated that bortezomib with chemotherapy has acceptable toxicity and remarkable activity in patients with relapsed ALL failing 2–3 previous regimens. We evaluated bortezomib in combination with chemotherapy in 30 and 7 children with B‐cell precursor (BCP ) and T‐cell ALL , respectively. Bortezomib (1·3 mg/m²/dose) was administered intravenously on days 1, 4, 8, and 11. Chemotherapy agents were the same as those used in the TACL trial, consisting of dexamethasone, doxorubicin, vincristine and pegylated asparaginase. Three patients (8·1%) died due to infections. Twenty‐seven patients (72·9%) achieved CR or CR with incomplete platelet recovery (CR p). Fourteen had minimal residual disease (MRD ) lower than 0·1%. Twenty‐two of 30 BCP ‐ALL patients (73·3%) and 5/7 patients (71%) with T‐cell ALL achieved CR /CR p. The 2‐year overall survival (OS ) is 31·3%; CR /CR p patients with an MRD response had a remarkable 2‐year OS of 68·4%. These data confirm that the combination of bortezomib with chemotherapy is a suitable/effective option for childhood relapsed/refractory ALL .     

Bortezomib combined with rituximab and dexamethasone is an active regimen for patients with relapsed and chemotherapy-refractory mantle cell lymphoma

Background

Bortezomib belongs to a new class of anti-cancer agents, the proteasome inhibitors, and has documented activity in multiple myeloma and mantle cell lymphoma. Preclinical studies suggest that bortezomib has synergistic activity with rituximab, which provides a rationale for the exploration of treatment combinations.

Design and Methods

The activity and safety of bortezomib in combination with rituximab and dexamethasone were investigated in patients with relapsed or chemotherapy-refractory mantle cell lymphoma. A treatment cycle consisted of bortezomib (1.3 mg/m² on days 1, 4, 8, and 11; six 21-day cycles), rituximab (375 mg/m², day 1) and dexamethasone (40 mg orally, days 1 to 4). Responding patients received four consolidating doses of rituximab. Sixteen patients with progressive mantle cell lymphoma after a median of three prior lines of therapy were enrolled.

Results

The overall response rate was 81.3% (13 patients), with seven patients achieving a complete response (43.8%). Six of these patients were also negative for disease activity by positron emission tomography scanning. The median progression-free survival and overall survival were 12.1 and 38.6 months, respectively. In patients achieving a complete response, the median progression-free survival and overall survival have not yet been reached. Adverse events (greater than grade II) included thrombocytopenia (37.5%), fatigue (18.8%) and peripheral neuropathy (12.5%). Two patients discontinued bortezomib because of grade III neuropathy.

Conclusions

Bortezomib combined with rituximab and dexamethasone has promising activity and manageable toxicity in patients with heavily pretreated mantle cell lymphoma. Achievement of complete response emerged as an important factor for sustained disease control.This trial was registered at www.clinicaltrials.gov as #NCT00261612.