PBRT is a type of external beam radiation therapy in which a beam of Proton particles are used to irradiate cancer tissue. It has been claimed that the main advantage of proton therapy is its ability to more precisely localize the radiation dosage to the tumor tissue and thereby improve tumor control, without causing significant damage to the surrounding tissues. This theoretical consideration was however disproved in a study published in the Jan 2, 2013 issue of the JNCI. In this study, data was gathered following prostate cancer treatment of over 22,000 medicare beneficiaries, with either IMRT (Intensity Modulated Radiation Therapy) or PBRT. The authors noted that PBRT was not superior to IMRT with regards to efficacy or toxicity, after one year. PBRT was however twice as expensive as IMRT. It therefore remains to be seen if third party payors will warm up to PBRT, with the expansion of PBRT centers across the country.
Author: RR
AVASTIN® (Bevacizumab)
The FDA on January 23, 2013 approved AVASTIN® for use in combination with fluoropyrimidine-irinotecan or fluoropyrimidine-oxaliplatin based chemotherapy, for the treatment of patients with metastatic colorectal cancer (mCRC) whose disease has progressed on a first-line AVASTIN® – containing regimen. The FDA initially approved AVASTIN® in 2004 for the first-line treatment of patients with metastatic carcinoma of the colon and rectum (in combination with intravenous 5-fluorouracil-based chemotherapy). AVASTIN® is a product of Genentech U.S., Inc.
Reduced Lung-Cancer Mortality with Low-Dose Computed Tomographic Screening
SUMMARY: The National Lung Screening Trial (NLST) enrolled 53,454 individuals at high risk for lung cancer and randomly assigned them to undergo three annual screenings with either non-contrast, low-dose CT scan (LDCT) or single-view posteroanterior chest X-ray. This study demonstrated a 20% reduction in the risk of death from lung cancer in the group of people who were screened with LDCT compared to those who were screened with chest X-ray (P=0.004). Based on this study and data, the American Cancer Society has recommended lung cancer screening for individuals 55 to 74 years of age who are in fairly good health, have at least a 30 pack-year smoking history and are either still smoking or have quit smoking within the past 15 years. If a person remains in good health, annual LDCT is continued until the age of 74. Smokers should be counseled to quit smoking. Further more, people with abnormal scans should receive appropriate care and follow up. Lung cancer screening with LDCT is presently not covered by most insurance plans. The National Lung Screening Trial Research Team. N Engl J Med 2011; 365:395-409
Final Results of a Phase 2 Open-Label, Monotherapy Efficacy and Safety Study of Quizartinib (AC220) in Patients with FLT3-ITD Positive or Negative Relapsed/Refractory Acute Myeloid Leukemia After Second-Line Chemotherapy or Hematopoietic Stem Cell Transplantation
SUMMARY: FLT3-ITD (FMS-like tyrosine kinase 3 – Internal Tandem Duplications) mutations are seen in approximately a third of the patients with AML and are associated with early relapse and poor survival. Quizartinib is an oral tyrosine kinase inhibitor, which has demonstrated activity in patients with both wild type FLT3 as well as those with FLT3 mutations. In this phase II trial, 333 patients were enrolled and divided into 2 cohorts – patients older than 60 years and those between 18 and 60 years of age. The data presented here relates to cohort 2 (younger cohort) which included 137 patients with AML, who either relapsed or were refractory to second line chemotherapy or relapsed after hematopoietic stem cell transplantation (HSCT). Of these patients, 99 were FLT3 -ITD mutation positive and 38 were FLT3 wild type. The dose of Quizartinib was 90 mg/day for women and 135 mg/day for men and was given continuously in 28-day cycles. This dosing schedule was chosen because of the risk for QT interval prolongation, based on gender. The primary end point was a composite complete remission rate (CRc), which included complete remission, complete remission with incomplete platelet recovery (CRp) and complete remission with incomplete hematologic recovery (CRi). Patients with FLT3 mutations had a CRc of 44% with 4% CR and 40% CRi. The median duration of response was 11.3 weeks and the median overall survival was 23.1 weeks. This compared to a CRc of 34% for those with wild type FLT3. Thirty four percent (34%) of the patients were able to undergo HSCT following response to Quizartinib. The most common side effects included nausea, vomiting, QT prolongation, cytopenia, diarrhea and fatigue. The authors concluded that Quizartinib has significant activity in patients with resistant and refractory AML and can facilitate HCST in about a third of the treated patients. Levis MJ, Perl AE, Dombret H, et al. 54th ASH Annual Meeting and Exposition 2012, Abstract 673
Pomalidomide in Combination with Low-Dose Dexamethasone Demonstrates a Significant Progression Free Survival and Overall Survival Advantage, in Relapsed/Refractory MM A Phase 3, Multicenter, Randomized, Open-Label Study
SUMMARY: Pomalidomide (POM) is a novel, oral, immunomodulatory drug which is far more potent than Thalidomide (THALOMID® and Lenalidomide (REVLIMID®) and has been shown to be active in REVLIMID® and Bortezomib (VELCADE®) refractory patients. In this phase III trial, the efficacy and safety of POM given along with low-dose dexamethasone (LoDEX) (n=302) was compared with high-dose dexamethasone (HiDEX) (n=153) in patients who were refractory to both REVLIMID® and VELCADE®. The primary endpoint was Progression Free Survival (PFS). The Overall Survival (OS) was only evaluated if PFS was statistically significant. With a median follow up of 18 weeks, the PFS was significantly longer in the POM + LoDEX group compared to the HiDEX group (15.7 vs 8.0 weeks; hazard ratio [HR], 0.45; P < .001). Following interim analysis, the OS was significantly longer in the POM + LoDEX group compared to HiDEX group (median not reached vs 34 weeks; HR, 0.53; P< .001). The authors concluded that this oral treatment regimen should be the new standard of care for patients who have disease refractory to REVLIMID® and VELCADE®. Carfilzomib (KYPROLIS®), a new parenteral proteasome inhibitor is another option for patients with resistant and refractory multiple myeloma. Dimopoulos MA, Lacy MQ, Moreau P, et al. 54th ASH Annual Meeting and Exposition 2012, LBA-6
A Phase 1/2 Study of Weekly MLN9708, an Investigational Oral Proteasome Inhibitor, in Combination with Lenalidomide and Dexamethasone in Patients with Previously Untreated Multiple Myeloma (MM)
SUMMARY: Bortezomib (VELCADE®) is a parenteral proteosome inhibitor with remarkable activity in multiple myeloma. This agent however, can be associated with neuropathy in about 30- 40% of the patients, when given intravenously twice a week, and in about 10-15% of patients when given subcutaneously. MLN9708 is an oral, reversible proteasome inhibitor with favorable toxicity profile and lower incidence of peripheral neuropathy (PN). In the phase I component of this trial, 15 patients were enrolled and a maximum tolerated dose of 4 mg of MLN9708, taken orally once a week, was established. For the phase II component of this study, 50 treatment naïve patients with multiple myeloma were enrolled and MLN9708 was given at a dose of 4 mg orally on days 1, 8, and 15, in combination with lenalidomide (REVLIMID®) (25 mg once daily on days 1 to 21) and dexamethasone (40 mg on days 1, 8, 15, and 22) every 28 days for up to 12 cycles. Patients subsequently went on to receive maintenance therapy with MLN9708 once a week until progression. In this regimen, MLN9708 was essentially substituted for VELCADE®. The overall response rate was 96%, with Very Good Partial Response seen in more than 44% of patients and 26% Complete Response rate. More importantly grade 1 neuropathy was only seen in 8% and grade 3 neuropathy developed in 3% of the patients. The authors concluded that the responses with this new combination is similar to the VRD (VELCADE®, REVLIMID®, and Dexamethasone) regimen but with significantly less neuropathy and more importantly, all three drugs can be given orally. Kumar SK, Berdeja JG, Niesvizky R, et al. 54th ASH Annual Meeting and Exposition 2012, Abstract 332
Cardiovascular Events and Intensity of Treatment in Polycythemia Vera
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
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
ICLUSIG® (Ponatinib)
ICLUSIG® (Ponatinib): The FDA on December 17, 2012 granted accelerated approval to ICLUSIG® for the treatment of adult patients with chronic phase, accelerated phase, or blast phase chronic myeloid leukemia (CML) that is resistant or intolerant to prior tyrosine kinase inhibitor therapy or Philadelphia chromosome positive acute lymphoblastic leukemia (Ph+ALL) that is resistant or intolerant to prior tyrosine kinase inhibitor therapy. ICLUSIG® is available as oral tablets and is a product of ARIAD Pharmaceuticals, Inc.