Owen A. O'Connor

Multicenter Phase II Study of Bortezomib in Patients With Relapsed or Refractory Mantle Cell Lymphoma

PURPOSEnEvaluate response rate, duration of response (DOR), time-to-progression (TTP), overall survival (OS), and safety of bortezomib treatment in patients with relapsed or refractory mantle cell lymphoma (MCL).nnnPATIENTS AND METHODSnBortezomib 1.3 mg/m(2) was administered on days 1, 4, 8, and 11 of a 21-day cycle, for up to 17 cycles. Response and progression were determined using International Workshop Response Criteria, both using data from independent radiology review and by the investigators. Primary efficacy analyses were based on data from independent radiology review.nnnRESULTSnIn total, 155 patients were treated. Median number of prior therapies was one (range, one to three). Response rate in 141 assessable patients was 33% including 8% complete response (CR)/unconfirmed CR. Median DOR was 9.2 months. Median TTP was 6.2 months. Results by investigator assessments were similar. Median OS has not been reached after a median follow-up of 13.4 months. The safety profile of bortezomib was similar to previous experience in relapsed multiple myeloma. The most common adverse events grade 3 or higher were peripheral neuropathy (13%), fatigue (12%), and thrombocytopenia (11%). Death from causes that were considered to be treatment related was reported for 3% of patients.nnnCONCLUSIONnThese results confirm the activity of bortezomib in relapsed or refractory MCL, with predictable and manageable toxicities. Bortezomib provides significant clinical activity in terms of durable and complete responses, and may therefore represent a new treatment option for this population with usually very poor outcome. Studies of bortezomib-based combinations in MCL are ongoing.

Phase II Clinical Experience With the Novel Proteasome Inhibitor Bortezomib in Patients With Indolent Non-Hodgkin's Lymphoma and Mantle Cell Lymphoma

PURPOSEnTo determine the antitumor activity of the novel proteasome inhibitor bortezomib in patients with indolent and mantle-cell lymphoma (MCL).nnnPATIENTS AND METHODSnPatients with indolent and MCL were eligible. Bortezomib was given at a dose of 1.5 mg/m2 on days 1, 4, 8, and 11. Patients were required to have received no more than three prior chemotherapy regimens, with at least 1 month since the prior treatment, 3 months from prior rituximab, and 7 days from prior corticosteroids; absolute neutrophil count more than 1,500/microL (500/microL if documented bone marrow involvement); and platelet count more than 50,000/microL.nnnRESULTSnTwenty-six patients were registered, of whom 24 were assessable. Ten patients had follicular lymphoma, 11 had MCL, three had small lymphocytic lymphoma (SLL) or chronic lymphocytic leukemia (CLL), and two had marginal zone lymphoma. The overall response rate was 58%, with one complete remission (CR), one unconfirmed CR (CRu), and four partial remissions (PR) among patients with follicular non-Hodgkins lymphoma (NHL). All responses were durable, lasting from 3 to 24+ months. One patient with MCL achieved a CRu, four achieved a PR, and four had stable disease. One patient with MCL maintained his remission for 19 months. Both patients with marginal zone lymphoma achieved PR lasting 8+ and 11+ months, respectively. Patients with SLL or CLL have yet to respond. Overall, the drug was well tolerated, with only one grade 4 toxicity (hyponatremia). The most common grade 3 toxicities were lymphopenia (n = 14) and thrombocytopenia (n = 7).nnnCONCLUSIONnThese data suggest that bortezomib was well tolerated and has significant single-agent activity in patients with certain subtypes of NHL.

Navitoclax, a targeted high-affinity inhibitor of BCL-2, in lymphoid malignancies: a phase 1 dose-escalation study of safety, pharmacokinetics, pharmacodynamics, and antitumour activity.

BACKGROUNDnProteins of the BCL-2 family regulate clonal selection and survival of lymphocytes, and are frequently overexpressed in lymphomas. Navitoclax is a targeted high-affinity small molecule that inhibits the anti-apoptotic activity of BCL-2 and BCL-XL. We aimed to assess the safety and antitumour activity of navitoclax in patients with lymphoid tumours, and establish the drugs pharmacokinetic and pharmacodynamic profiles.nnnMETHODSnIn this phase 1 dose-escalation study, patients (aged ≥18 years) with relapsed or refractory lymphoid malignancies were enrolled and treated at seven sites in the USA between November, 2006, and November, 2009. A modified Fibonacci 3+3 design was used to assign patients to receive oral navitoclax once daily by one of two dosing schedules: intermittently for the first 14 days of a 21-day cycle (14/21) at doses of 10, 20, 40, 80, 110, 160, 225, 315, or 440 mg/day; or continuously for 21 days of a 21-day cycle (21/21) at doses of 200, 275, 325, or 425 mg/day. Study endpoints were safety, maximum tolerated dose, pharmacokinetic profile, pharmacodynamic effects on platelets and T cells, and antitumour activity. This trial is registered with ClinicalTrials.gov, number NCT00406809.nnnFINDINGSn55 patients were enrolled (median age 59 years, IQR 51-67), 38 to receive the 14/21 dosing schedule, and 17 to receive the 21/21 dosing schedule. Common toxic effects included grade 1 or 2 anaemia (41 patients), infection (39), diarrhoea (31), nausea (29), and fatigue (21); and grade 3 or 4 thrombocytopenia (29), lymphocytopenia (18), and neutropenia (18). On the intermittent 14/21 schedule, dose-limiting toxic effects were hospital admissions for bronchitis (one) and pleural effusion (one), grade 3 increase in aminotransferases (one), grade 4 thrombocytopenia (one), and grade 3 cardiac arrhythmia (one). To reduce platelet nadir associated with intermittent 14/21 dosing, we assessed a 150 mg/day lead-in dose followed by a continuous 21/21 dosing schedule. On the 21/21 dosing schedule, two patients did not complete the first cycle and were excluded from assessment of dose-limiting toxic effects; dose-limiting toxic effects were grade 4 thrombocytopenia (one), grade 3 increase in aminotransferases (one), and grade 3 gastrointestinal bleeding (one). Navitoclax showed a pharmacodynamic effect on circulating platelets and T cells. Clinical responses occurred across the range of doses and in several tumour types. Ten of 46 patients with assessable disease had a partial response, and these responders had median progression-free survival of 455 days (IQR 40-218).nnnINTERPRETATIONnNavitoclax has a novel mechanism of peripheral thrombocytopenia and T-cell lymphopenia, attributable to high-affinity inhibition of BCL-XL and BCL-2, respectively. On the basis of these findings, a 150 mg 7-day lead-in dose followed by a 325 mg dose administered on a continuous 21/21 dosing schedule was selected for phase 2 study.nnnFUNDINGnAbbott Laboratories, Genentech, and National Cancer Institute, National Institutes of Health.

Clinical Experience With Intravenous and Oral Formulations of the Novel Histone Deacetylase Inhibitor Suberoylanilide Hydroxamic Acid in Patients With Advanced Hematologic Malignancies

PURPOSEnTo document the toxicity and activity of the histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) in patients with pretreated hematologic malignancies.nnnPATIENTS AND METHODSnTwo formulations of SAHA (intravenous [IV] and oral) have been assessed in two consecutive phase I trials. In both trials, dose escalation was performed in parallel and independently in patients with solid tumors and hematologic malignancies. Eligible patients were required to have adequate hepatic and renal function, an absolute neutrophil count > or = 500/microL and a platelet count more than 25,000/mL. All patients provided informed consent for study inclusion.nnnRESULTSnA total of 39 patients with hematologic malignancy were enrolled (14 on IV SAHA and 25 on oral SAHA), of whom 35 were treated. The spectrum of diseases included patients with diffuse large B-cell lymphoma (n = 12), Hodgkins disease (HD; n = 12), multiple myeloma (n = 2), T-cell lymphoma (n = 3), mantle cell lymphoma (n = 2), small lymphocytic lymphoma (n = 2), and myeloid leukemia (n = 2). Major adverse events with the oral formulation included fatigue, diarrhea, anorexia, and dehydration, whereas myelosuppression and thrombocytopenia were more prominent with the IV formulation. Typically, the hematologic toxicities resolved shortly after SAHA was stopped. There was no neutropenic fever or neutropenic sepsis. Reduction in measurable tumor was observed in five patients. One patient with transformed small lymphocytic lymphoma met criteria for complete response, whereas another met the criteria for partial response (PR). One patient with refractory HD had a PR, whereas three patients had stable disease for up to 9 months.nnnCONCLUSIONnThese results suggest that SAHA has activity in hematologic malignancies including HD and select subtypes of non-Hodgkins lymphoma.

Pralatrexate in Patients With Relapsed or Refractory Peripheral T-Cell Lymphoma: Results From the Pivotal PROPEL Study

PURPOSEnPeripheral T-cell lymphoma (PTCL) is a poor prognosis subtype of non-Hodgkins lymphoma with no accepted standard of care. This study evaluated the efficacy and tolerability of pralatrexate, a novel antifolate with promising activity.nnnPATIENTS AND METHODSnPatients with independently confirmed PTCL who progressed following ≥ 1 line of prior therapy received pralatrexate intravenously at 30 mg/m(2)/wk for 6 weeks in 7-week cycles. Primary assessment of response was made by independent central review using the International Workshop Criteria. The primary end point was overall response rate. Secondary end points included duration of response, progression-free survival (PFS), and overall survival (OS).nnnRESULTSnOf 115 patients enrolled, 111 were treated with pralatrexate. The median number of prior systemic therapies was three (range, 1 to 12). The response rate in 109 evaluable patients was 29% (32 of 109), including 12 complete responses (11%) and 20 partial responses (18%), with a median DoR of 10.1 months. Median PFS and OS were 3.5 and 14.5 months, respectively. The most common grade 3/4 adverse events were thrombocytopenia (32%), mucositis (22%), neutropenia (22%), and anemia (18%).nnnCONCLUSIONnTo our knowledge, PROPEL (Pralatrexate in Patients with Relapsed or Refractory Peripheral T-Cell Lymphoma) is the largest prospective study conducted in patients with relapsed or refractory PTCL. Pralatrexate induced durable responses in relapsed or refractory PTCL irrespective of age, histologic subtypes, amount of prior therapy, prior methotrexate, and prior autologous stem-cell transplant. These data formed the basis for the US Food and Drug Administration approval of pralatrexate, the first drug approved for this disease.

Bortezomib in patients with relapsed or refractory mantle cell lymphoma: updated time-to-event analyses of the multicenter phase 2 PINNACLE study

BACKGROUNDnWe previously reported results of the phase 2, multicenter PINNACLE study, which confirmed the substantial single-agent activity of bortezomib in patients with relapsed or refractory mantle cell lymphoma (MCL).nnnMATERIALS AND METHODSnWe report updated time-to-event data, in all patients and by response to treatment, after extended follow-up (median 26.4 months).nnnRESULTSnMedian time to progression (TTP) was 6.7 months. Median time to next therapy (TTNT) was 7.4 months. Median overall survival (OS) was 23.5 months. In responding patients, median TTP was 12.4 months, median duration of response (DOR) was 9.2 months, median TTNT was 14.3 months, and median OS was 35.4 months. Patients achieving complete response had heterogeneous disease characteristics; among these patients, median TTP and DOR were not reached, and median OS was 36.0 months. One-year survival rate was 69% overall and 91% in responding patients. Median OS from diagnosis was 61.1 months, after median follow-up of 63.7 months. Activity was seen in patients with refractory disease and patients relapsing following high-intensity treatment. Toxicity was generally manageable.nnnCONCLUSIONSnSingle-agent bortezomib is associated with lengthy responses and notable survival in patients with relapsed or refractory MCL, with considerable TTP and TTNT in responding patients, suggesting substantial clinical benefit.

Risk-Adapted Dose-Dense Immunochemotherapy Determined by Interim FDG-PET in Advanced-Stage Diffuse Large B-Cell Lymphoma

PURPOSE In studies of diffuse large B-cell lymphoma, positron emission tomography with [(18)F]fluorodeoxyglucose (FDG-PET) performed after two to four cycles of chemotherapy has demonstrated prognostic significance. However, some patients treated with immunochemotherapy experience a favorable long-term outcome despite a positive interim FDG-PET scan. To clarify the significance of interim FDG-PET scans, we prospectively studied interim FDG-positive disease within a risk-adapted sequential immunochemotherapy program. PATIENTS AND METHODS From March 2002 to November 2006, 98 patients at Memorial Sloan-Kettering Cancer Center received induction therapy with four cycles of accelerated R-CHOP (rituximab + cyclophosphamide, doxorubicin, vincristine, and prednisone) followed by an interim FDG-PET scan. If the FDG-PET scan was negative, patients received three cycles of ICE (ifosfamide, carboplatin, and etoposide) consolidation therapy. If residual FDG-positive disease was seen, patients underwent biopsy; if the biopsy was negative, they also received three cycles of ICE. Patients with a positive biopsy received ICE followed by autologous stem-cell transplantation. RESULTS At a median follow-up of 44 months, overall and progression-free survival were 90% and 79%, respectively. Ninety-seven patients underwent interim FDG-PET scans; 59 had a negative scan, 51 of whom are progression free. Thirty-eight patients with FDG-PET-positive disease underwent repeat biopsy; 33 were negative, and 26 remain progression free after ICE consolidation therapy. Progression-free survival of interim FDG-PET-positive/biopsy-negative patients was identical to that in patients with a negative interim FDG-PET scan (P = .27). CONCLUSION Interim or post-treatment FDG-PET evaluation did not predict outcome with this dose-dense, sequential immunochemotherapy program. Outside of a clinical trial, we recommend biopsy confirmation of an abnormal interim FDG-PET scan before changing therapy.

A Phase 1 Dose Escalation Study of the Safety and Pharmacokinetics of the Novel Proteasome Inhibitor Carfilzomib (PR-171) in Patients with Hematologic Malignancies

Purpose: Carfilzomib (formerly PR-171) is a novel proteasome inhibitor of the epoxyketone class that is selective and structurally distinct from bortezomib. Proteasome inhibition by carfilzomib is mechanistically irreversible. Consequently, proteasome inhibition is more sustained with carfilzomib than with bortezomib. Experimental Design: In a phase 1 trial evaluating the safety and efficacy of carfilzomib in relapsed or refractory hematologic malignancies, eight dose groups of three to six patients received 5 consecutive days of carfilzomib i.v. push at doses of 1.2, 2.4, 4, 6, 8.4, 11, 15, and 20 mg/m2 within 14-day cycles. Results: Twenty-nine patients enrolled that were relapsed or refractory after at least two prior therapies. Nonhematologic toxicities included fatigue, nausea, and diarrhea in more than one third of patientsmostly grade 1 or 2 in severity. At 20 mg/m2, grade 3 febrile neutropenia and grade 4 thrombocytopenia were reported, establishing 15 mg/m2 as the maximum tolerated dose. No grade 3 or 4 peripheral neuropathies were reported. Antitumor activity was observed at doses 11 mg/m2: one unconfirmed complete response (mantle cell), one partial response (multiple myeloma), and two minimal responses (multiple myeloma and Waldenstrms macroglobulinemia). Conclusion: This is the first clinical use of carfilzomib that shows tolerability and clinical activity in multiple hematologic malignancies using consecutive-day dosing. (Clin Cancer Res 2009;15(22):708591)

A Phase I Single-Agent Study of Twice-Weekly Consecutive-Day Dosing of the Proteasome Inhibitor Carfilzomib in Patients with Relapsed or Refractory Multiple Myeloma or Lymphoma

Purpose: Carfilzomib is a next-generation, selective, proteasome inhibitor with clinical activity in relapsed and/or refractory multiple myeloma. The objectives of this phase I study were to establish the safety, tolerability, pharmacokinetic, and pharmacodynamic profiles of escalating doses of carfilzomib in patients with relapsed or refractory hematologic malignancies. Experimental design: Carfilzomib (doses ranging from 1.2–27 mg/m2) was administered i.v. on 2 consecutive days for 3 weeks of a 4-week cycle. Single-agent dose escalation (n = 37) was followed by a dose-expansion phase (n = 11) that comprised 2 cohorts (carfilzomib or carfilzomib + dexamethasone). During dose expansion, carfilzomib was administered starting with 20 mg/m2 during the first week (days 1, 2) and then escalated to 27 mg/m2 thereafter. Results: A maximum tolerated dose (MTD) was not reached during dose escalation. Dosing in the expansion cohort was well tolerated. Adverse events were manageable and primarily of grade I or II. The main hematologic adverse events of ≥ grade III were anemia and thrombocytopenia. Notably, there were no observations of grade III or more peripheral neuropathy. Carfilzomib was cleared rapidly with an elimination half-life of less than 30 minutes but still induced dose-dependent inhibition of the 20S chymotrypsin-like proteasome activity. At doses of 15 to 27 mg/m2, there was evidence of activity among patients with multiple myeloma and with non-Hodgkin lymphoma. Conclusions: Escalated dosing of carfilzomib on a schedule of 2 consecutive days for 3 weeks of a 4-week cycle was tolerable and showed promising activity. This dose regimen has been selected for ongoing and future clinical studies, including PX-171-003A1 and the pivotal trial ASPIRE. Clin Cancer Res; 18(17); 4830–40. ©2012 AACR.

Primary mediastinal large B-cell lymphoma: optimal therapy and prognostic factor analysis in 141 consecutive patients treated at memorial Sloan Kettering from 1980 to 1999

Primary mediastinal large B‐cell lymphoma (PMLBL) is a distinct clinicopathological entity with unclear prognostic factors and optimal treatment approach. To elucidate an optimal treatment and identify predictive factors, a retrospective analysis of 141 consecutive patients was undertaken. Patients received cyclophosphamide, hydroxydaunomycin, Oncovin, prednisone (CHOP)‐like therapy, the non‐Hodgkin lymphoma (NHL)‐15 regimen or upfront autologous stem cell transplantation (ASCT) on Institutional Review Board approved trials or according to the institutional guidelines. Evaluation included lactate dehydrogenase, International Prognostic Index (IPI) assessment, computed tomography scan and gallium imaging. With a median follow‐up of 10·9u2003years, event‐free survival (EFS) and overall survival (OS) was 50% and 66% respectively. EFS/OS for CHOP/CHOP‐like, NHL‐15 and upfront ASCT was 34/51%, 60/84% and 60/78% respectively. CHOP/CHOP‐like regimens had inferior EFS and OS versus NHL‐15 or upfront ASCT (Pu2003<u20030·001). A total of 23% of patients received radiotherapy. Multivariate analysis revealed the following outcome predictors: for EFS, greater than or equal to two extranodal sites and initial therapy received (NHL‐15 or upfront ASCT); for OS, only initial therapy with NHL‐15. We conclude: (i) dose‐dense chemotherapy with NHL‐15 may be superior to CHOP for PMLBL; (ii) The impact of consolidative radiotherapy requires randomised controlled trials; (iii) The age‐adjusted IPI did not predict survival in this analysis; (iv) high‐dose chemotherapy/ASCT should be reserved for upfront anthracycline‐based therapy failure or in clinical trials for high‐risk patients.