SUMMARY: The significance of maintaining a hematocrit less than 45% to prevent cardiovascular events, was evaluated in this randomized clinical study. Patients with JAK2-positive polycythemia vera (n=365) treated with phlebotomy, hydroxyurea, or both were randomized to receive either a more intensive treatment to maintain a target hematocrit of less than 45% (low-hematocrit group, n=182) or less intensive treatment to a target hematocrit of 45 to 50% (high-hematocrit group, n= 183). The primary end point was the time until death from cardiovascular events or major thrombotic episodes. The secondary end points included cardiovascular events, cardiovascular hospitalizations, incidence of cancer, progression to myelofibrosis, myelodysplasia or leukemia and hemorrhage. At a median follow-up of 31 months, the primary end point was recorded in 5 of 182 patients (2.7%) in the low-hematocrit group and 18 of 183 patients (9.8%) in the high-hematocrit group ( P=0.007). There were no significant differences in the secondary end points. The authors concluded that maintaining a lower hematocrit can lower the risk of cardiovascular death and major thrombosis. Marchioli R, Finazzi G, Specchia G, et al. N Engl J Med 2013; 368:22-33
Category: Meeting Updates
The Bruton’s Tyrosine Kinase (BTK) Inhibitor Ibrutinib (PCI-32765) Promotes High Response Rate, Durable Remissions, and Is Tolerable in Treatment Naïve (TN) and Relapsed or Refractory (RR) Chronic Lymphocytic Leukemia (CLL) or Small Lymphocytic Lymphoma (SLL) Patients Including Patients with High-Risk (HR) Disease New and Updated Results of 116 Patients in a Phase Ib/II Study
SUMMARY: BTK is predominantly expressed in B-cells and is a mediator of B-cell receptor signaling in normal and transformed B-cells. BTK is necessary for the proliferation and survival of B-cell tumors. Ibrutinib (PCI-32765) is an oral, irreversible inhibitor of BTK and thereby inhibits cell proliferation and promotes programmed cell death (Apoptosis). In this phase Ib/II trial, 116 patients with CLL were enrolled who were either treatment naïve or had relapsed/ refractory CLL or Small Lymphocytic Lymphoma. Patients with high risk cytogenetic features were included as well and patients were divided into 5 groups and received Ibrutinib at fixed doses of 420mg or 840mg daily, until disease progression. The primary objective of this study was to determine the safety of the two dosing regimens. Secondary objectives were to assess efficacy, pharmacokinetics and long-term safety. In the treatment naïve group, the Complete Response (CR) was seen in 10% of the patients, PR (Partial Response) in 61% and the estimated 22 month PFS (Progression Free Survival) and OS (Overall Survival) was 96%. In the relapsed/refractory group, the CR was 3% and PR was 64%, whereas in the high risk cytogenetics group, there were no CR’s and PR was 50%. Estimated 22 month PFS and OS for the relapsed/refractory as well as high risk groups were 76% and 85% respectively. This benefit was achieved with minimal toxicity which included diarrhea, fatigue, skin rash and arthralgias. The authors concluded that treatment with Ibrutinib resulted in significant disease control extending beyond 12 months with minimal adverse events in this difficult-to-treat CLL patients. Byrd JC, Furman RR, Coutre S, et al. 54th ASH Annual Meeting and Exposition 2012, Abstract 189
Phase II Multicenter Study of Single-Agent Lenalidomide in Subjects with Mantle Cell Lymphoma Who Relapsed or Progressed After or Were Refractory to Bortezomib The MCL-001 “EMERGE” Study
SUMMARY: Mantle cell lymphomas constitute approximately 5% of all Non Hodgkins lymphomas and have a high relapse rate following dose-intensive therapies. Bortezomib (VELCADE®) is approved for the treatment of relapsed mantle cell myeloma (MCL) and has a response rate of 30%. This open label, phase II trial, evaluated the safety and efficacy of Lenalidomide (REVLIMID®) in 134 patients with MCL who have had prior therapy with Rituximab (RITUXAN®), Cyclophosphamide, Anthracycline and had relapsed or progressed in less than 12 months or were refractory to VELCADE®. Patients had a median of 4 prior treatments. Treatment consisted of single agent REVLIMID® 25 mg/day given on days 1 thru 21 of a 28-day cycle, given until disease progression or unacceptable toxicity. The primary endpoints were overall response rate (ORR) and duration of response. The secondary endpoints included complete response (CR), Progression Free Survival (PFS), time to progression, overall survival (OS) and safety. In this heavily pretreated patient population the ORR was 28% and the median duration of response of 16.6 months. The CR was 8%, PFS was 4.0 months, and OS was 19.0 months. The most common grade 3/4 adverse events were cytopenias. The authors concluded that REVLIMID® resulted in rapid and durable responses in patients with relapsed/refractory MCL. Goy A, Sinha R, Williams ME, et al. 54th ASH Annual Meeting and Exposition 2012, Abstract 905
Results of a randomized phase 2 study of PD 0332991, a cyclin-dependent kinase (CDK) 4/6 inhibitor, in combination with letrozole vs letrozole alone for first-line treatment of ER+/HER2- advanced breast cancer (BC)
SUMMARY: PD 0332991 is an oral, selective inhibitor of CDK4/6 kinases. This agent interrupts cellular DNA synthesis by inhibiting the progression of the cell cycle from G1 to S phase and thus prevents tumor cell growth. The results presented, includes the pooled data from the study of 2 cohorts of patients. Both groups included postmenopausal women with advanced breast cancer and ER positive, HER2 negative tumors. Patients were randomized 1:1 to receive either letrozole (FEMARA®) along with PD 0332991 or FEMARA® alone. Group 1 enrolled 66 patients and Group 2 enrolled 99 patients. Group 2 patient tumors were also evaluated for the biomarkers cyclinD1 amplification and/or loss of p16, by FISH analysis. For both these study groups, the primary endpoint was Progression Free Survival (PFS). Secondary endpoints included response rates, overall survival, safety, and biomarker correlates. Data from the pooled analysis which included 165 women from both the groups demonstrated a median PFS of 26.1 months for the combination compared to 7.5 months with FEMARA® alone. This represented a 63% reduction in risk of progression (hazard ratio =0.37; P < 001). The most common adverse events noted in the combination group included uncomplicated neutropenia, anemia, and fatigue. Biomarkers expression (cyclinD1 amplification and/or loss of p16) had no impact on outcomes suggesting that the biomarker for PD0332991 may be the estrogen receptor itself rather than CDK4/6 kinases. Finn RS, Crown JP, Lang I, et al. CTRC-AACR San Antonio Breast Cancer Symposium 2012; Abstract S1-6.
Prospective study of treatment pattern, effectiveness, and safety of zoledronic acid (ZOL) therapy beyond 24 months subgroup analysis of patients (pts) with metastatic bone disease (MBD) from breast cancer (BC)
SUMMARY:There is not much data on the effectiveness and safety of Zoledronic acid (ZOMETA®) beyond 2 years. Two studies one from Belgium and the other from Japan shed some light on this issue. In the prospective multicenter Belgian trial, 108 women with breast cancer prior to enrollment had received at least 24 months of therapy with ZOMETA® infusions given every 3 to 4 weeks and 21% had received at least 48 months of therapy. They were followed for 18 months and monitored for Skeletal Related Events (SRE’s), Osteo Necrosis of the Jaw bone (ONJ), renal failure and hypocalcemia. During this follow up period, SRE’s were low and 83% of the women were free of SRE’s. ONJ was seen in 7 patients (4.5%). The rate of ONJ however rose to 11% after any invasive dental procedure. The risk of renal failure was low but increased to 12%when the dose of ZOMETA® was not adjusted for renal function. The Japanese study was a retrospective analysis of 83 patients who had been treated with ZOMETA® for at least 24 months (median 33 months). SRE’s were low and the frequency of ONJ was 3.6% compared to 2.4% for those patients who had been ZOMETA® for shorter periods. Both these studies demonstrated that longer duration of therapy with ZOMETA® resulted in increased rate of ONJ. Therefore, particular attention should be paid to prevent this complication by adhering to proper dental hygiene and avoiding dental trauma and extractions. Van den Wyngaert T, Delforge M, Doyen C, et al. and Suzuki Y, Saito Y, Ogiya R, et al. CTRC-AACR San Antonio Breast Cancer Symposium 2012; Poster P3-13-01 and P3-13-02.
Final analysis of overall survival for the phase III CONFIRM trial fulvestrant 500 mg versus 250 mg
SUMMARY: Fulvestrant (FASOLODEX®) is an Estrogen Receptor (ER) antagonist and downregulates the cellular levels of ER in a dose-dependent manner. The CONFIRM trial is a phase III study in which postmenopausal women with estrogen receptor (ER) positive advanced breast cancer, who had progressed after prior endocrine therapy, were randomized to be treated with either FASLODEX® 500 mg (n=362) or FASLODEX® 250 mg (n=374) every 28 days. The primary end point for this study was Progression Free Survival (PFS). In the primary analysis, FASLODEX® 500 mg was associated with a statistically significant increase in PFS compared with FASLODEX® 250 mg. Even though there was a trend towards improved overall survival (OS) with the higher dose, this was not statistically significant. In the updated second survival analysis presented at this symposium, the median OS trend prevailed with FASLODEX® 500mg compared with FASLODEX® 250mg, given every 28 days (26.4 months vs 22.3 months, P=0.16). This translated into a 4 month increase in median overall survival and a 19% reduction in the risk of death. The authors concluded that the higher dose of FASLODEX® may indeed confer some survival benefit to this patient subsets. Di Leo A, Jerusalem G, Petruzelka L, et al. CTRC-AACR San Antonio Breast Cancer Symposium; 2012; Abstract S1-4.
Neurocognitive impact in adjuvant chemotherapy for breast cancer linked to fatigue a prospective functional MRI study
SUMMARY: Cognitive impairment in patients with breast cancer has been frequently attributed to chemotherapy (Chemo Brain) without any data supporting this hypothesis. Utilizing functional magnetic resonance imaging, brain function was tested while the patients were performing a working memory task in the scanner, before adjuvant treatment and then one month after adjuvant treatment. Sixty six breast cancer patients with Stages 0-IIIA were studied and their cognitive function was compared with 32 healthy controls. Patients on treatment were receiving either an anthracyline-based adjuvant chemotherapy regimen (n = 29) or radiotherapy (n = 37). Patients self-reported on levels of cognitive functioning and fatigue after each imaging study. Pretreatment brain imaging revealed decreased functioning in the frontal lobe of the brain (responsible for memory and cognition), compared to the controls and this cognitive impairment was most severe in patients awaiting chemotherapy, whereas the radiotherapy group fell between the pre-chemotherapy and control group. Of Interest, the decreased functioning in the frontal lobe area before treatment predicted the severity of fatigue. Further, those with greater fatigue experienced greater cognitive impairment over time. The authors concluded that the cognitive problems are probably related to worry and fatigue prior to treatment intervention rather than the treatment itself. They recommend identifying patients at risk and early intervention. Cimprich B, Hayes DF, Askren MK, et al. CTRC-AACR San Antonio Breast Cancer Symposium, 2012; Abstract S6-3.
ATLAS 10 v 5 years of adjuvant tamoxifen (TAM) in ER+ disease effects on outcome in the first and in the second decade after diagnosis
SUMMARY: Historically, adjuvant treatment with tamoxifen beyond five years has not been recommended, as the benefit of tamoxifen beyond five years was unknown but there was an increased risk of endometrial cancer. (Tamoxifen Treatment for Breast Cancer and Risk of Endometrial Cancer: A Case-Control Study, J Natl Cancer Inst 2005; 97: 375-384). The ATLAS trial has now shed some light on the duration of tamoxifen treatment. In this study, 6846 women with ER positive breast cancer were enrolled between 1996 and 2005 and following five years of adjuvant tamoxifen were randomized to five additional years of tamoxifen or observation. Women who continued on tamoxifen had a 25% lower recurrence rate and 29% lower breast cancer mortality rate compared with women who stopped tamoxifen after five years. This significant benefit was seen in the second decade after diagnosis with little benefit seen in the 5-9 year period after diagnosis. There was a higher cumulative risk of death from endometrial cancer for those who continued tamoxifen beyond 5 years compared to those who did not (0.4% vs 0.2%). It appears that the reduction in breast cancer deaths outweigh the risk of endometrial cancer and other adverse events associated with longer duration of tamoxifen use. This new information will help physicians make appropriate treatment recommendations for those patients on adjuvant tamoxifen. Davis C, Hongchao P, Godwin J, et al. CTRC-AACR San Antonio Breast Cancer Symposium, 2012; Abstract S1-2.
Chemotherapy prolongs survival for isolated local or regional recurrence of breast cancer the CALOR trial (Chemotherapy as Adjuvant for Locally Recurrent breast cancer; IBCSG 27-02, NSABP B-37, BIG 1-02)
SUMMARY: Approximately 5% to 15% of all breast cancer patients present with local and/or regional recurrences. The role of adjuvant chemotherapy after resection of an isolated recurrence of breast cancer is unknown. To address this, in the CALOR trial, 162 patients with recurrent tumors underwent surgery and were then randomized to receive either four cycles of a multidrug chemotherapy regimen of investigator’s choice (n=85) or observation (n=77). The median age was 56 years. The treatment groups were well balanced and 68% and 58% of patients in the observation and treatment arms respectively received prior adjuvant chemotherapy. The median time to recurrence was 5 years in the treatment group and 6 years in the observation group. The primary end point was disease free survival (DFS). The 5-year DFS rate for the chemotherapy group and observation group was 69% vs 57% respectively. This translated into a relative risk reduction of 41% (hazard ratio [HR], 0.59; P = 0.045). The 5-year overall survival rate between the chemotherapy group and observation group was 88% vs 76% with a 59% reduction in the relative risk for death for patients treated with chemotherapy (HR, 0.41; P = 0.02). In patients with ER-negative tumors, the 5-year DFS was 67% in the treatment arm versus 35% in the control group (HR = 0.32; P = 0.007). This data supports the role of chemotherapy for patients with completely resected isolated locoregional recurrences of breast cancer. Aebi S, Gelber S, Láng I, et al. Presented at: CTRC-AACR San Antonio Breast Cancer Symposium, 2012. Abstract S3-2.
Intermittent (IAD) versus continuous androgen deprivation (CAD) in hormone sensitive metastatic prostate cancer (HSM1PC) patients (pts) Results of S9346 (INT-0162), an international phase III trial
SUMMARY: Preclinical data had suggested that Intermittent Androgen Deprivation (IAD) could prolong response to therapy and alleviate side effects related to androgen deprivation. In this Phase III trial, 3040 enrolled patients with hormone sensitive metastatic prostate cancer, with PSA ≥ 5 ng/ml, were treated for 7 months with ZOLADEX® (Goserelin) plus CASODEX® (Bicalutamide). After 7 months of this combination therapy, 1535 eligible patients achieved a PSA of ≤4.0 ng/ml. These patients were then randomized to either continue ZOLADEX® plus CASODEX® (Continuous Androgen Deprivation -CAD) or receive this combination intermittently (Intermittent Androgen Deprivation – IAD). The primary endpoint was overall survival. The median Overall Survival from the time of randomization in the CAD group was 5.8 years versus 5.1 years for the IAD group. However, a subset analysis surprisingly revealed that patients with minimal metastatic disease had a statistically significant survival advantage with CAD whereas those with extensive metastatic disease had a better survival with IAD. Counter intuitive as it may be, this study has clearly suggested that the choice of CAD versus IAD should be based on the extent of metastatic disease, in patients with hormone sensitive prostate cancer. Hussain M, Tangen CM, Higano CS, et al. J Clin Oncol 2012; 30, 2012 (suppl; abstr 4)