Betsy LaPlant

The relationship between six-month progression-free survival and 12-month overall survival end points for phase II trials in patients with glioblastoma multiforme

Common end points for phase II trials in patients with glioblastoma multiforme (GBM) are six-month progression-free survival (PFS6) and 12-month overall survival (OS12). OS12 can be accurately measured but may be confounded with subsequent therapies upon progression, whereas the converse is true for PFS6. Our goal was to assess the relationship between these end points separately for phase II trials in patients with newly diagnosed GBM and patients with recurrent GBM. Data were pooled from 11 North Central Cancer Treatment Group trials for patients with newly diagnosed GBM (n = 1348). All patients received radiotherapy and pharmaceutical therapy (before, during, or after radiotherapy). Data were pooled from 16 trials that used various pharmaceuticals in treating patients for recurrent GBM (n = 345). All trial regimens were declared nonefficacious by predefined criteria. Overall per-patient concordance was estimated with a kappa statistic. The relationship between OS12 and PFS6 across study arms was assessed by weighted linear regression and Pearsons correlation. Simulation was used to determine the agreement of study outcomes when using PFS6 versus OS12 end points. Cox models with progression status as a time-dependent variable and Kaplan-Meier estimators were used to ascertain the association between progression-free survival status and overall survival. At present, 97% of the patients with newly diagnosed GBM and 95% of those with recurrent GBM have died. The PFS6 and OS12 were 43% and 41%, respectively, for patients with newly diagnosed disease and 9% and 14% for patients with recurrent disease. There was only moderate concordance between the end points on both the patient level and the study level. For the simulation studies, we established phase II efficacy criteria for each end point by using the pooled estimates of OS12 (PFS6) as historical controls. The study decisions made using PFS6 and OS12 were in agreement 88% and 90% of the time for the trials of newly diagnosed and recurrent disease, respectively. Finally, there was a strong association between progression-free survival status and overall survival. PFS6 seems to be a reasonable end point for phase II trials in patients with recurrent glioblastoma.

A phase II trial of the oral mTOR inhibitor everolimus in relapsed aggressive lymphoma

The phosphatidylinositol 3-kinase signal transduction pathway members are often activated in tumor samples from patients with non-Hodgkins lymphoma (NHL). Everolimus is an oral agent that targets the raptor mammalian target of rapamycin (mTORC1). The goal of this trial was to learn the antitumor activity and toxicity of single-agent everolimus in patients with relapsed/refractory aggressive NHL. Patients received everolimus 10 mg PO daily. Response was assessed after two and six cycles, and then every three cycles until progression. A total of 77 patients with a median age of 70 years were enrolled. Patients had received a median of three previous therapies and 32% had undergone previous transplant. The overall response rate (ORR) was 30% (95% confidence interval: 20–41%), with 20 patients achieving a partial remission and 3 a complete remission unconfirmed. The ORR in diffuse large B cell was 30% (14/47), 32% (6/19) in mantle cell and 38% (3/8) in follicular grade 3. The median duration of response was 5.7 months. Grade 3 or 4 anemia, neutropenia and thrombocytopenia occurred in 14, 18 and 38% of patients, respectively. Everolimus has single-agent activity in relapsed/refractory aggressive NHL and provides proof-of-concept that targeting the mTOR pathway is clinically relevant.

Phase I Study of Ipilimumab, an Anti–CTLA-4 Monoclonal Antibody, in Patients with Relapsed and Refractory B-Cell Non–Hodgkin Lymphoma

Purpose: The growth of non–Hodgkin lymphomas can be influenced by tumor–immune system interactions. Cytotoxic T-lymphocyte antigen 4 (CTLA-4) is a negative regulator of T-cell activation that serves to dampen antitumor immune responses. Blocking anti–CTLA-4 monoclonal antibodies improves host resistance to immunogenic tumors, and the anti–CTLA-4 antibody ipilimumab (MDX-010) has clinical activity against melanoma, prostate, and ovarian cancers. Experimental Design: We did a phase I trial of ipilimumab in patients with relapsed/refractory B-cell lymphoma to evaluate safety, immunologic activity, and potential clinical efficacy. Treatment consisted of ipilimumab at 3 mg/kg and then monthly at 1 mg/kg × 3 months (dose level 1), with subsequent escalation to 3 mg/kg monthly × 4 months (dose level 2). Results: Eighteen patients were treated, 12 at the lower dose level and 6 at the higher dose level. Ipilimumab was generally well tolerated, with common adverse events attributed to it, including diarrhea, headache, abdominal pain, anorexia, fatigue, neutropenia, and thrombocytopenia. Two patients had clinical responses; one patient with diffuse large B-cell lymphoma had an ongoing complete response (>31 months), and one with follicular lymphoma had a partial response lasting 19 months. In 5 of 16 cases tested (31%), T-cell proliferation to recall antigens was significantly increased (>2-fold) after ipilimumab therapy. Conclusions: Blockade of CTLA-4 signaling with the use of ipilimumab is well tolerated at the doses used and has antitumor activity in patients with B-cell lymphoma. Further evaluation of ipilimumab alone or in combination with other agents in B-cell lymphoma patients is therefore warranted. (Clin Cancer Res 2009;15(20):6446–53)

A Phase II trial of the oral mTOR inhibitor everolimus in relapsed Hodgkin lymphoma

Everolimus is an oral antineoplastic agent that targets the raptor mammalian target of rapamycin (mTORC1). The phosphatidylinositol 3‐kinase/mTOR signal transduction pathway has been demonstrated to be activated in tumor samples from patients with Hodgkin lymphoma (HL). The goal of this trial was to learn the antitumor activity and toxicity of everolimus in patients with relapsed/refractory HL. Patients were eligible if they had measurable disease, a platelet count >75,000, and an absolute neutrophil count >1,000. Patients received everolimus 10 mg PO daily. Dose reductions were allowed. Response was assessed after two and six cycles and then every three cycles until progression. Patients could remain on drug until progression or toxicity. Nineteen patients were enrolled. Median age was 37 years (range, 27–68). Patients had received a median of six prior therapies (range, 3–14) and 84% had undergone prior autologous stem cell transplant. The ORR was 47% (95% CI: 24–71%) with eight patients achieving a PR and one patient achieving a CR. The median TTP was 7.2 months. Four responders remained progression free at 12 months. Patients received a median of seven cycles of therapy. Of the 19 patients, one remains on therapy at 36 months; the others went off study because of progressive disease (16), toxicity (1), and death from infection (1). Four patients experienced a Grade 3 or higher pulmonary toxicity. Everolimus has single‐agent activity in relapsed/refractory HL and provides proof‐of‐concept that targeting the mTOR pathway in HL is clinically relevant. Am. J. Hematol., 2010.

Lenalidomide Combined With R-CHOP Overcomes Negative Prognostic Impact of Non–Germinal Center B-Cell Phenotype in Newly Diagnosed Diffuse Large B-Cell Lymphoma: A Phase II Study

PURPOSE Lenalidomide has significant single-agent activity in relapsed diffuse large B-cell lymphoma (DLBCL). We demonstrated that lenalidomide can be safely combined with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone); this new combination is known as R2CHOP. The goal of this phase II study was to evaluate the efficacy of this combination in newly diagnosed DLBCL. PATIENTS AND METHODS Eligible patients were adults with newly diagnosed untreated stages II to IV CD20(+) DLBCL. Patients received lenalidomide 25 mg orally per day on days 1 through 10 with standard-dose R-CHOP every 21 days for six cycles. All patients received pegfilgrastim on day 2 of each cycle and aspirin prophylaxis throughout. DLBCL molecular subtype was determined by tumor immunohistochemistry and classified as germinal center B-cell (GCB) versus non-GCB in the R2CHOP patients and 87 control patients with DLBCL from the Lymphoma Database who were treated with conventional R-CHOP. RESULTS In all, 64 patients with DLBCL were enrolled, and 60 were evaluable for response. The overall response rate was 98% (59 of 60) with 80% (48 of 60) achieving complete response. Event-free survival and overall survival (OS) rates at 24 months were 59% (95% CI, 48% to 74%) and 78% (95% CI, 68% to 90%), respectively. In R-CHOP patients, 24-month progression-free survival (PFS) and OS were 28% versus 64% (P < .001) and 46% versus 78% (P < .001) in non-GCB DLBCL versus GCB DLBCL, respectively. In contrast, there was no difference in 24-month PFS or OS for R2CHOP patients on the basis of non-GCB and GCB subtype (60% v 59% [P = .83] and 83% v 75% [P = .61] at 2 years, respectively). CONCLUSION R2CHOP shows promising efficacy in DLBCL. The addition of lenalidomide appears to mitigate a negative impact of non-GCB phenotype on patient outcome.

Phase I Trial of Daily Oral Polyphenon E in Patients With Asymptomatic Rai Stage 0 to II Chronic Lymphocytic Leukemia

PURPOSE To define the optimal dose of Polyphenon E for chronic daily administration and tolerability in patients with chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS Previously untreated patients with asymptomatic Rai stage 0 to II CLL were eligible for participation. Polyphenon E with a standardized dose of epigallocatechin-3-gallate (EGCG) was administered using the standard phase I design with three to six patients per dose level (range, 400 to 2,000 mg by mouth twice a day). Trough plasma EGCG levels were measured 1 month after initiation of therapy. Response was classified using the National Cancer Institute (NCI) Working Group (WG) Criteria. RESULTS Thirty-three eligible patients were accrued to dose levels 1 to 8. The maximum-tolerated dose was not reached. The most common adverse effects included transaminitis (33%, all grade 1), abdominal pain (30% grade 1, 0% grade 2, and 3% grade 3), and nausea (39% grade 1 and 9% grade 2). One patient experienced an NCI WG partial remission. Other signs of clinical activity were also observed, with 11 patients (33%) having a sustained > or = 20% reduction in absolute lymphocyte count (ALC) and 11 (92%) of 12 patients with palpable adenopathy experiencing at least a 50% reduction in the sum of the products of all nodal areas during treatment. Trough plasma EGCG levels after 1 month of treatment ranged from 2.9 to 3,974 ng/mL (median, 40.4 ng/mL). CONCLUSION Daily oral EGCG in the Polyphenon E preparation was well tolerated by CLL patients in this phase I trial. Declines in ALC and/or lymphadenopathy were observed in the majority of patients. A phase II trial to evaluate efficacy using 2,000 mg twice a day began in November 2007.

CD49d expression is an independent predictor of overall survival in patients with chronic lymphocytic leukaemia: a prognostic parameter with therapeutic potential

In vitro studies have demonstrated that surface expression of CD49d on chronic lymphocytic leukaemia (CLL) B cells facilitates leukaemic cell–stromal interactions by binding to fibronectin. This interaction reduces both spontaneous and drug‐induced apoptosis. The present study measured CD49d expression by flow cytometry in a cohort of untreated CLL patients previously accrued to a prospective observational study and evaluated the relationship with overall survival (OS). Among the 158 CLL patients tested, the percentage of leukaemic B cells expressing CD49d ranged from 0 to 100%. When all risk factors were treated as continuous variables, CD49d expression showed moderate correlation with expression of ZAP‐70 (r = 0·54; P < 0·0001) and CD38 (r = 0·58; P < 0·0001) but not %IGHV mutation. As a continuous variable, CD49d expression strongly correlated with OS (P < 0·0001). Recursive partitioning analysis suggested the 45% threshold of CD49d expression best predicted OS. Multivariate analysis, controlling for disease stage, ZAP‐70, IGHV status and fluorescent in situ hybridization defects identified CD49d as an independent predictor of OS and was a better predictor of clinical outcome than ZAP‐70, IGHV, or cytogenetics. This observational cohort study suggests that CLL B‐cell expression of CD49d is an easily measurable and independent predictor of OS and CD49d expression in CLL. Importantly, anti‐CD49d antibodies are already approved for treatment of other human diseases. Clinical testing of anti‐CD49d therapy in CLL appears warranted.

Phase II Trial of the Oral Mammalian Target of Rapamycin Inhibitor Everolimus in Relapsed or Refractory Waldenström Macroglobulinemia

PURPOSE The phosphatidylinositol 3-kinase/mammalian target of rapamycin (mTOR) signal transduction pathway controls cell proliferation and survival. Everolimus is an oral agent targeting raptor mTOR (mTORC1). The trials goal was to determine the antitumor activity and safety of single-agent everolimus in patients with relapsed/refractory Waldenström macroglobulinemia (WM). PATIENTS AND METHODS Eligible patients had measurable disease (immunoglobulin M monoclonal protein > 1,000 mg/dL with > 10% marrow involvement or nodal masses > 2 cm), a platelet count more than 75,000 x 10(6)/L, a neutrophil count more than 1,000 x 10(6)/L, and a creatinine and bilirubin less than 2 x the laboratory upper limit of normal. Patients received everolimus 10 mg orally daily and were evaluated monthly. Tumor response was assessed after cycles 2 and 6 and then every three cycles until progression. Results Fifty patients were treated. The median age was 63 years (range, 43 to 85 years). The overall response rate (complete response plus partial remission [PR] plus minimal response [MR]) was 70% (95% CI, 55% to 82%), with a PR of 42% and 28% MR. The median duration of response and median progression-free survival (PFS) have not been reached. The estimated PFS at 6 and 12 months is 75% (95% CI, 64% to 89%) and 62% (95% CI, 48% to 80%), respectively. Grade 3 or higher related toxicities were observed in 56% of patients. The most common were hematologic toxicities with cytopenias. Pulmonary toxicity occurred in 10% of patients. Dose reductions due to toxicity occurred in 52% of patients. CONCLUSION Everolimus has high single-agent activity with an overall response rate of 70% and manageable toxicity in patients with relapsed WM and offers a potential new therapeutic strategy for this patient group.

The treatment of recurrent/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) with everolimus results in clinical responses and mobilization of CLL cells into the circulation.

Patients with recurrent/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) often have chemotherapy‐resistant disease, resulting in poor prognosis. The aim of this study was to learn if inhibition of the mammalian target of rapamycin (mTOR) would produce tumor responses.

Phase 2 trial of daily, oral polyphenon E in patients with asymptomatic, Rai stage 0 to II chronic lymphocytic leukemia

The objective of the current study was to follow up the results of phase 1 testing by evaluating the clinical efficacy of the green tea extract Polyphenon E for patients with early stage chronic lymphocytic leukemia (CLL).