Nancy L. Bartlett

Randomized Controlled Trial of Yttrium-90–Labeled Ibritumomab Tiuxetan Radioimmunotherapy Versus Rituximab Immunotherapy for Patients With Relapsed or Refractory Low-Grade, Follicular, or Transformed B-Cell Non-Hodgkin’s Lymphoma

PURPOSE Radioimmunotherapy combines biologic and radiolytic mechanisms to target and destroy tumor cells, thus offering a needed therapeutic alternative for refractory non-Hodgkins lymphoma (NHL) patients. This phase III randomized study compares the novel radioimmunotherapy yttrium-90 ((90)Y) ibritumomab tiuxetan with a control immunotherapy, rituximab, in 143 patients with relapsed or refractory low-grade, follicular, or transformed CD20(+) transformed NHL. PATIENTS AND METHODS Patients received either a single intravenous (IV) dose of (90)Y ibritumomab tiuxetan 0.4 mCi/kg (n = 73) or rituximab 375 mg/m(2) IV weekly for four doses (n = 70). The radioimmunotherapy group was pretreated with two rituximab doses (250 mg/m(2)) to improve biodistribution and one dose of indium-111 ibritumomab tiuxetan for imaging and dosimetry. The primary end point, overall response rate (ORR), was assessed by an independent, blinded, lymphoma expert panel. RESULTS ORR was 80% for the (90)Y ibritumomab tiuxetan group versus 56% for the rituximab group (P =.002). Complete response (CR) rates were 30% and 16% in the (90)Y ibritumomab tiuxetan and rituximab groups, respectively (P =.04). An additional 4% achieved an unconfirmed CR in each group. Kaplan-Meier estimated median duration of response was 14.2 months in the (90)Y ibritumomab tiuxetan group versus 12.1 months in the control group (P =.6), and time to progression was 11.2 versus 10.1 months (P =.173) in all patients. Durable responses of > or = 6 months were 64% versus 47% (P =.030). Reversible myelosuppression was the primary toxicity noted with (90)Y ibritumomab tiuxetan. CONCLUSION Radioimmunotherapy with (90)Y ibritumomab tiuxetan is well tolerated and produces statistically and clinically significant higher ORR and CR compared with rituximab alone.

Brentuximab Vedotin (SGN-35) for Relapsed CD30-Positive Lymphomas

BACKGROUND Hodgkins lymphoma and anaplastic large-cell lymphoma are the two most common tumors expressing CD30. Previous attempts to target the CD30 antigen with monoclonal-based therapies have shown minimal activity. To enhance the antitumor activity of CD30-directed therapy, the antitubulin agent monomethyl auristatin E (MMAE) was attached to a CD30-specific monoclonal antibody by an enzyme-cleavable linker, producing the antibody-drug conjugate brentuximab vedotin (SGN-35). METHODS In this phase 1, open-label, multicenter dose-escalation study, we administered brentuximab vedotin (at a dose of 0.1 to 3.6 mg per kilogram of body weight) every 3 weeks to 45 patients with relapsed or refractory CD30-positive hematologic cancers, primarily Hodgkins lymphoma and anaplastic large-cell lymphoma. Patients had received a median of three previous chemotherapy regimens (range, one to seven), and 73% had undergone autologous stem-cell transplantation. RESULTS The maximum tolerated dose was 1.8 mg per kilogram, administered every 3 weeks. Objective responses, including 11 complete remissions, were observed in 17 patients. Of 12 patients who received the 1.8-mg-per-kilogram dose, 6 (50%) had an objective response. The median duration of response was at least 9.7 months. Tumor regression was observed in 36 of 42 patients who could be evaluated (86%). The most common adverse events were fatigue, pyrexia, diarrhea, nausea, neutropenia, and peripheral neuropathy. CONCLUSIONS Brentuximab vedotin induced durable objective responses and resulted in tumor regression for most patients with relapsed or refractory CD30-positive lymphomas in this phase 1 study. Treatment was associated primarily with grade 1 or 2 (mild-to-moderate) toxic effects. (Funded by Seattle Genetics; ClinicalTrials.gov number, NCT00430846.).

Results of a Pivotal Phase II Study of Brentuximab Vedotin for Patients With Relapsed or Refractory Hodgkin's Lymphoma

PURPOSE Brentuximab vedotin is an antibody-drug conjugate (ADC) that selectively delivers monomethyl auristatin E, an antimicrotubule agent, into CD30-expressing cells. In phase I studies, brentuximab vedotin demonstrated significant activity with a favorable safety profile in patients with relapsed or refractory CD30-positive lymphomas. PATIENTS AND METHODS In this multinational, open-label, phase II study, the efficacy and safety of brentuximab vedotin were evaluated in patients with relapsed or refractory Hodgkins lymphoma (HL) after autologous stem-cell transplantation (auto-SCT). Patients had histologically documented CD30-positive HL by central pathology review. A total of 102 patients were treated with brentuximab vedotin 1.8 mg/kg by intravenous infusion every 3 weeks. In the absence of disease progression or prohibitive toxicity, patients received a maximum of 16 cycles. The primary end point was the overall objective response rate (ORR) determined by an independent radiology review facility. RESULTS The ORR was 75% with complete remission (CR) in 34% of patients. The median progression-free survival time for all patients was 5.6 months, and the median duration of response for those in CR was 20.5 months. After a median observation time of more than 1.5 years, 31 patients were alive and free of documented progressive disease. The most common treatment-related adverse events were peripheral sensory neuropathy, nausea, fatigue, neutropenia, and diarrhea. CONCLUSION The ADC brentuximab vedotin was associated with manageable toxicity and induced objective responses in 75% of patients with relapsed or refractory HL after auto-SCT. Durable CRs approaching 2 years were observed, supporting study in earlier lines of therapy.

Brentuximab Vedotin (SGN-35) in Patients With Relapsed or Refractory Systemic Anaplastic Large-Cell Lymphoma: Results of a Phase II Study

PURPOSE Systemic anaplastic large-cell lymphoma (ALCL) is an aggressive subtype of T-cell lymphoma characterized by the uniform expression of CD30. The antibody-drug conjugate brentuximab vedotin delivers the potent antimicrotubule agent monomethylauristatin E to CD30-positive malignant cells. A phase II multicenter trial was conducted to evaluate the efficacy and safety of brentuximab vedotin in patients with relapsed or refractory systemic ALCL. PATIENTS AND METHODS Patients with systemic ALCL and recurrent disease after at least one prior therapy received brentuximab vedotin 1.8 mg/kg intravenously every 3 weeks over 30 minutes as an outpatient infusion. The primary end point of the study was overall objective response rate as assessed by independent central review. RESULTS Of 58 patients treated in the study, 50 patients (86%) achieved an objective response, 33 patients (57%) achieved a complete remission (CR), and 17 patients (29%) achieved a partial remission. The median durations of overall response and CR were 12.6 and 13.2 months, respectively. Grade 3 or 4 adverse events in ≥ 10% of patients were neutropenia (21%), thrombocytopenia (14%), and peripheral sensory neuropathy (12%). CONCLUSION Brentuximab vedotin induced objective responses in the majority of patients and CRs in more than half of patients with recurrent systemic ALCL. Targeted therapy with this CD30-directed antibody-drug conjugate may be an effective treatment for relapsed or refractory systemic ALCL and warrants further studies in front-line therapy.

Ibrutinib as Initial Therapy for Patients with Chronic Lymphocytic Leukemia

BACKGROUND Chronic lymphocytic leukemia (CLL) primarily affects older persons who often have coexisting conditions in addition to disease-related immunosuppression and myelosuppression. We conducted an international, open-label, randomized phase 3 trial to compare two oral agents, ibrutinib and chlorambucil, in previously untreated older patients with CLL or small lymphocytic lymphoma. METHODS We randomly assigned 269 previously untreated patients who were 65 years of age or older and had CLL or small lymphocytic lymphoma to receive ibrutinib or chlorambucil. The primary end point was progression-free survival as assessed by an independent review committee. RESULTS The median age of the patients was 73 years. During a median follow-up period of 18.4 months, ibrutinib resulted in significantly longer progression-free survival than did chlorambucil (median, not reached vs. 18.9 months), with a risk of progression or death that was 84% lower with ibrutinib than that with chlorambucil (hazard ratio, 0.16; P<0.001). Ibrutinib significantly prolonged overall survival; the estimated survival rate at 24 months was 98% with ibrutinib versus 85% with chlorambucil, with a relative risk of death that was 84% lower in the ibrutinib group than in the chlorambucil group (hazard ratio, 0.16; P=0.001). The overall response rate was higher with ibrutinib than with chlorambucil (86% vs. 35%, P<0.001). The rates of sustained increases from baseline values in the hemoglobin and platelet levels were higher with ibrutinib. Adverse events of any grade that occurred in at least 20% of the patients receiving ibrutinib included diarrhea, fatigue, cough, and nausea; adverse events occurring in at least 20% of those receiving chlorambucil included nausea, fatigue, neutropenia, anemia, and vomiting. In the ibrutinib group, four patients had a grade 3 hemorrhage and one had a grade 4 hemorrhage. A total of 87% of the patients in the ibrutinib group are continuing to take ibrutinib. CONCLUSIONS Ibrutinib was superior to chlorambucil in previously untreated patients with CLL or small lymphocytic lymphoma, as assessed by progression-free survival, overall survival, response rate, and improvement in hematologic variables. (Funded by Pharmacyclics and others; RESONATE-2 ClinicalTrials.gov number, NCT01722487.).

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

PURPOSE Peripheral 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. PATIENTS AND METHODS Patients 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). RESULTS Of 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%). CONCLUSION To 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.

Stanford V and Radiotherapy for Locally Extensive and Advanced Hodgkin’s Disease: Mature Results of a Prospective Clinical Trial

PURPOSE To provide more mature data on the efficacy and complications of a brief, dose-intense chemotherapy regimen plus radiation therapy (RT) to bulky disease sites for locally extensive and advanced-stage Hodgkins disease. PATIENTS AND METHODS One hundred forty-two patients with stage III or IV or locally extensive mediastinal stage I or II Hodgkins disease received Stanford V chemotherapy for 12 weeks followed by 36-Gy RT to initial sites of bulky (> or =5 cm) or macroscopic splenic disease. Freedom from progression (FFP), overall survival (OS), and freedom from second relapse (FF2R) were determined using life-table estimates. Outcomes were analyzed according to the international prognostic score. Late effects of treatment were recorded in follow-up. RESULTS With a median follow-up of 5.4 years, the 5-year FFP was 89% and the OS was 96%. No patient progressed during treatment, and there were no treatment-related deaths. FFP was significantly superior among patients with a prognostic score of 0 to 2 compared with those with a score of 3 and higher (94% v 75%, P <.0001). No secondary leukemia was observed. To date, there have been 42 pregnancies after treatment. Among 16 patients who relapsed, the FF2R was 69% at 5 years. CONCLUSION These data confirm our preliminary report that Stanford V chemotherapy with RT to bulky disease sites is highly effective in locally extensive and advanced Hodgkins disease. It is most important to compare this approach with standard doxorubicin, bleomycin, vinblastine, and dacarbazine chemotherapy in the ongoing intergroup trial (E2496) to determine whether Stanford V with or without RT represents a therapeutic advance.

Bendamustine Is Effective Therapy in Patients With Rituximab-Refractory, Indolent B-cell Non-Hodgkin Lymphoma: Results From a Multicenter Study

Bendamustine hydrochloride is a novel alkylating agent. In this multicenter study, the authors evaluated the efficacy and toxicity of single‐agent bendamustine in patients with rituximab‐refractory, indolent B‐cell lymphoma.

A Phase II study of SGN‐30 (anti‐CD30 mAb) in Hodgkin lymphoma or systemic anaplastic large cell lymphoma

SGN‐30, a chimeric anti‐CD30 monoclonal antibody, has demonstrated potent preclinical antitumour activity in both Hodgkin lymphoma (HL) and anaplastic large cell lymphoma (ALCL). We conducted an open‐label, Phase II study to determine the safety and objective response rate of SGN‐30 in 79 patients with refractory/recurrent HL (n = 38) or systemic ALCL (n = 41). Each course of SGN‐30 comprised 6 weekly intravenous infusions, followed by a 2‐week treatment‐free period. Patients had received a median of 3 (range 1–5) prior regimens of chemotherapy or systemic therapy. The initial 40 patients received 6 mg/kg weekly; the latter 39 patients received 12 mg/kg weekly. In the ALCL group, two patients achieved a complete response and five additional patients achieved a partial response, with response durations ranging from 27 to 1460+ d. No objective responses were observed in the HL group; however, 11 patients (29%) had stable disease (duration 62–242 days). Although adverse events were common, most were mild or moderate, and no specific pattern of adverse events was observed in either disease group. These results demonstrate that weekly administration of SGN‐30 is safe, with modest clinical activity in patients with ALCL.

Brief chemotherapy, Stanford V, and adjuvant radiotherapy for bulky or advanced-stage Hodgkin's disease: a preliminary report.

PURPOSE Although survival rates have improved for patients with bulky and advanced-stage Hodgkins disease (HD), current treatments entail substantial acute morbidity and risks for late effects such as infertility, second malignancies, and cardiopulmonary toxicities. A novel, brief chemotherapy regimen (doxorubicin, vinblastine, mechlorethamine, vincristine, bleomycin, etoposide, and prednisone [Stanford V]) was designed to shorten the duration of treatment, significantly reduce cumulative doses of alkylating agents, doxorubicin, and bleomycin, and maintain dose-intensity (DI). This brief chemotherapy was combined with radiation therapy (RT) to bulky disease sites. METHODS Since May 1989, 65 previously untreated patients were treated for stage II HD with bulky mediastinal involvement (n = 21) or for stage III or IV HD (n = 44). Patients received weekly chemotherapy for 12 weeks. Consolidative RT was given to the first 25 patients to sites of initial bulky disease or radiographic abnormalities that persisted after chemotherapy; in the remaining 40 patients, RT was limited to bulky disease (adenopathy > or = 5 cm and/or macroscopic splenic nodules defined by computed tomography [CT]). RESULTS With a median follow-up period of 2 years, actuarial 3-year survival rate is 96% and failure-free survival (FFS) rate is 87%. The 3-year FFS rate is 100% for stage II patients with bulky mediastinal disease and 82% for patients with stage III to IV disease. There were no treatment-related deaths. In a preliminary analysis on a subset of patients, female and male fertility appears to be preserved. CONCLUSION These preliminary results indicate that the Stanford V chemotherapy regimen with or without RT is well-tolerated and effective therapy for bulky, limited-stage, and advanced-stage HD. Less cumulative exposure to alkylating agents, doxorubicin, and bleomycin and limited use of radiation is expected to decrease risks for second neoplasms and late cardiopulmonary toxicity. Based on these results, the Stanford V chemotherapy with or without RT regimen deserves further study in the context of a randomized clinical trial.