SUMMARY: Abiraterone acetate (ZYTIGA®) is a novel, targeted, oral androgen biosynthesis inhibitor that decreases androgen production in the adrenal glands, testes and prostate cancer cells by inhibiting a steroidal enzyme CYP17. This agent was approved by the FDA in April, 2011 for use in combination with prednisone for the treatment of patients with metastatic CRPC (Castrate Resistant Prostate Cancer), who have received prior chemotherapy containing docetaxel (TAXOTERE®). This approval was based on a randomized, placebo controlled phase III trial which included 1195 patients with metastatic CRPC, previously treated with one or two chemotherapy regimens, at least one of which contained TAXOTERE®. Patients were randomly assigned (2:1) to receive either ZYTIGA® plus low-dose prednisone (N=797) or placebo plus low dose prednisone (N=398). Treatment was continued until disease progression. The primary endpoint was overall survival. Results from a pre-specified interim analysis demonstrated that patients treated with ZYTIGA® plus low-dose prednisone showed a statistically significant improvement in overall survival as well secondary endpoints such as, time to PSA progression and radiographic progression-free survival. Treatment with ZYTIGA® resulted in a 35 percent reduction in the risk of death and a 36 percent increase in median survival compared with placebo. The most common adverse events were edema, hypertension, joint discomfort, diarrhea, hypokalemia, and hypophosphatemia. This novel therapeutic agent is a major and important medical advance in the management of patients with metastatic CRPC. With the availability of several new agents for the treatment of CRPC, it may be important to properly sequence these available drugs to get the best of each treatment intervention and thus improve overall survival. Annals of Oncology 21 (Supplement 8): viii1-viii12. 2010. Ref Type: Abstract
Category: Hem/Onc Updates
Dasatinib versus Imatinib in Newly Diagnosed Chronic-Phase Chronic Myeloid Leukemia
SUMMARY: This multicenter international phase III study evaluated the efficacy of Dasatinib (SPRYCEL®) versus Imatinib (GLEEVEC®) in newly diagnosed chronic phase Chronic Myeloid Leukemia patients. Of the 519 patients enrolled, 259 patients received SPRYCEL® at 100 mg daily whereas 260 patients received GLEEVEC® 400 mg daily. The complete cytogenetic response rate after one year for SPRYCEL® and GLEEVEC® was 77% versus 66% respectively and the major molecular response rate at 12 months was 46% vs 28% for the SPRYCEL® group and GLEEVEC® group respectively. Thrombocytopenia and pleural effusions were more often seen in the SPRYCEL® group. It was concluded that SPRYCEL® resulted in a significantly shorter time to achieve complete cytogenetic and major molecular responses. N Engl J Med 2010; 362:2260-2270.
Sunitinib Malate for the Treatment of Pancreatic Neuroendocrine Tumors
SUMMARY: Pancreatic neuroendocrine tumors account for approximately 5% of all pancreatic tumors and in general tend to be indolent tumors. In a randomized multicenter phase III trial, 171 patients with advanced, well-differentiated pancreatic neuroendocrine tumors, whose tumors had progressed in the prior 12 months were randomized to receive either Sunitinib (SUTENT®), a multitargeted tyrosine kinase inhibitor, at a dose of 37.5 mg qd or placebo. Following an interim analysis, this study was closed earlier than planned based on the superiority of SUTENT® over placebo. The median progression free survival was longer for those who received SUTENT® than those in the placebo group (11.4 versus 5.5 months). More patients in the SUTENT® group were alive at 6 months compared to the placebo group (92.6% versus 85.2%). N Engl J Med 2011; 364:501-513
Everolimus for Advanced Pancreatic Neuroendocrine Tumors
SUMMARY: Everolimus (AFINITOR®) is an oral mTOR (mammalian target of rapamycin) inhibitor, presently approved for the treatment of advanced renal cel carcinoma. Based on the established efficacy of AFINITOR® in phase II trials, a prospective, randomized, phase III study was conducted in which 410 patients with advanced, low grade or intermediate grade pancreatic neuroendocrine tumors with progression within the previous 12 months were randomized to receive AFINITOR®, at a dose of 10 mg QD (207 patients), or placebo (203 patients).The primary end point, progression free survival (PFS) was met, with a PFS of 11 months in the AFINITOR® group and 4.6 months in the placebo group. These benefits were accomplished with a low rate of grade III and IV toxicities. It appears that the mTOR pathway may play an important role in the molecular pathogenesis of pancreatic neuroendocrine tumors. N Engl J Med 2011; 364:514-523
Anaplastic Lymphoma Kinase Inhibition in Non Small Cell Lung Cancer
SUMMARY:The therapeutic target of interest is an aberrant fusion gene, EML4-ALK. EML4 (echinoderm microtubule-associated protein-like 4) – ALK (anaplastic lymphoma kinase) is a fusion-type oncoprotein and is tyrosine kinase. This oncoprotein/tyrosine kinase is found in 2-7% of all Non Small Cell Lung Cancers (NSCLC) and is generated due to an inversion in the short arm of chromosome 2. This oncoprotein is more prevalent in patients with adenocarcinoma who have little or no exposure to tobacco. Tyrosine kinases normally play an important role in cellular proliferation and differentiation. However with point mutations, translocation/rearrangement and amplifications of their respective genes, these tyrosine kinases can potentially cause malignancy. Such is the case with mutations or translocations of the Anaplastic Lymphoma Kinase gene (ALK). In an article published in the October 28, 2010 issue of the NEJM, Crizotinib an oral small molecule tyrosine kinase inhibitor of ALK tyrosine kinase resulted in an overall response rate of 57% in patients who had progressed on prior therapies. Stable disease was noted in 33% of the patients. This is remarkable considering that the response rates in this patient population treated with second line chemotherapy is around 10-15%. As we move forward, it is very likely that genotyping patients and tailoring therapy accordingly, will become standard practice. N Engl J Med 2010; 363:1693-1703
Randomized phase III trial comparing FOLFIRINOX (F 5FU/leucovorin [LV], irinotecan [I], and oxaliplatin [O]) versus gemcitabine (G) as first-line treatment for metastatic pancreatic adenocarcinoma (MPA) Preplanned interim analysis results of the PRODIGE 4/ACCORD 11 trial
SUMMARY: Adenocarcinoma of the pancreas is one of the hard-to-treat cancers for which chemotherapy has not demonstrated any survival benefit – that is, until now. In a recently presented randomized phase III trial at the ASCO 2010 meeting, 250 patients with metastatic pancreatic cancer were assigned to receive either single agent Gemcitabine (GEMZAR®) or a combination of fluorouracil, leucovorin, Irinotecan (CAMPTOSAR®) , and Oxaliplatin (ELOXATIN®) – (FOLFIRINOX regimen). Following an interim analysis, this trial had to be closed earlier than planned, based on the significantly positive results noted with the combination regimen. The median overall survival for patients in the FOLFIRINOX was 11.1 months compared with 6.8 months for those receiving single agent GEMZAR®. At one year, 48% of patients in the FOLFIRINOX group were alive compared to 20% for those in the GEMZAR® group. The median progression free survival was 6.4 months for the patients treated with FOLFIRINOX compared to 3.3 months for those treated with single agent GEMZAR®. Quality of life was also superior in the FOLFIRINOX group compared to those who were treated with GEMZAR®. For the very first time, we now have a combination chemotherapy regimen for advanced pancreatic cancer that confers survival benefit. J Clin Oncol 28:303s, 2010 (suppl; abstr 4010)
Phase III trial of bevacizumab (BEV) in the primary treatment of advanced epithelial ovarian cancer (EOC), primary peritoneal cancer (PPC), or fallopian tube cancer (FTC) A Gynecologic Oncology Group study
SUMMARY: The role of Bevacizumab (AVASTIN®) in the treatment of advanced ovarian cancer was evaluated in a large randomized double blind phase III trial. One thousand eight hundred and seventy three (1873) patients with stage III or IV disease, who were treatment naïve, were randomly assigned to one of three treatment groups – standard chemotherapy with paclitaxel and carboplatin given along with a placebo followed maintenance treatment with a placebo, standard chemotherapy given along with AVASTIN® followed by maintenance treatment with a placebo or standard chemotherapy given along with AVASTIN® followed by maintenance treatment with AVASTIN®. Patients receiving standard chemotherapy along with AVASTIN® followed by maintenance AVASTIN® had a median Progression Free Survival of 14.1 months compared to 10.3 months for those who received standard chemotherapy alone. Interestingly, outcomes in patients receiving standard chemotherapy along with AVASTIN® followed by placebo maintenance did no better than those who received standard chemotherapy alone. To date, addition of AVASTIN® to standard chemotherapy followed by AVASTIN® maintenance has not resulted in significant improvement in overall survival. J Clin Oncol 28:18s, 2010 (suppl; abstr LBA1)
Nilotinib versus Imatinib for Newly Diagnosed Chronic Myeloid Leukemia
SUMMARY: ENESTnd (Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Newly Diagnosed Patients) is a phase III, randomized, open-label, multicenter study comparing the efficacy and safety of Nilotinib (TASIGNA®), either 300 mg or 400 mg bid with GLEEVEC® (Imatinib) 400mg qd, in patients with newly diagnosed Ph+ CML in chronic phase. Of the 846 patients enrolled, 282 patients received TASIGNA® 300 mg bid, 281 patients received TASIGNA® 400 mg bid and 283 patients received GLEEVEC® 400 mg qd. With a median follow up of 18 months, the MMR (Major Molecular Response) was 66% for the TASIGNA® 300 mg bid group and 62% for the TASIGNA® 400 mg bid group compared with 40% for the GLEEVEC® 400 mg qd group. The median time to MMR amongst the patients who achieved MMR was faster for TASIGNA® 300 mg bid (5.7 months) and TASIGNA® 400 mg bid (5.8 months) groups of patients compared with GLEEVEC® 400 mg qd (8.3 months). The rates of complete cytogenetic response at 18 months were also significantly higher for both TASIGNA® groups – 85% in the TASIGNA® 300 mg bid group, 82% in the TASIGNA® 400 mg bid group and 74% in the GLEEVEC® 400 mg qd group. Fewer patients in the TASIGNA® groups progressed to accelerated phase or blast crises compared with GLEEVEC® group. Adverse effects more often seen with TASIGNA® included skin rash, headache, liver function abnormalities, high cholesterol, hyperglycemia, increased serum lipase, abnormal electrolyte levels and prolongation of the QT interval. The authors concluded that TASIGNA® at both 300 mg bid and 400 mg bid induced significantly higher and faster rates of MMR and complete cytogenetic remission compared with GLEEVEC® 400 mg qd. J Clin Oncol 28:15s, 2010 (suppl; abstr 6501)
Prednisone plus cabazitaxel or mitoxantrone for metastatic castration-resistant prostate cancer progressing after docetaxel treatment a randomised open-label trial
SUMMARY: The TROPIC trial (Treatment of Hormone-Refractory Metastatic Prostate Cancer Previously Treated With a docetaxel (TAXOTERE®)- Containing Regimen) involved 755 men in 26 countries with metastatic prostate cancer who were castration resistant. Patients were randomized to receive either Cabazitaxel (JEVTANA®) 25 mg/m2 or Mitoxantrone 12 mg/m2 three times a week and both groups received prednisone 10 mg daily through out the course of their treatment. The combination of JEVTANA® and prednisone resulted in median overall survival of 15.1 months compared to 12.7 months for the Mitoxantrone group. There was a 30% reduction in the risk of death for the JEVTANA® group. This led to the approval of JEVTANA® for the treatment of hormone-refractory metastatic prostate cancer, previously treated with a TAXOTERE® containing regimen. Lancet 2010;376:1147-1154
A phase III study (EMBRACE) of eribulin mesylate versus treatment of physician’s choice in patients with locally recurrent or metastatic breast cancer previously treated with an anthracycline and a taxane
SUMMARY: HALAVEN ® (Eribulin) is a non taxane inhibitor of microtubule dynamics and is a synthetic analog of halichondrin B, a product derived from a a sea sponge Halichodria okadai. It triggers apoptosis of cancer cells following prolonged mitotic inhibition. The EMBRACE trial is a randomized open label phase III study involving 762 heavily pretreated patients with locally recurrent or metastatic breast cancer. These patients must have had at least two prior chemotherapy regimens including taxanes and an anthracycline. Patients were randomized to either HALAVEN ® (508 patients) or to an approved treatment of their physician's choice and this could be single agent chemotherapy, hormonal therapy, biological therapy or palliative radiation therapy (254 patients). Nineteen percent of the patients had triple negative disease. There was a statistically significant improvement in overall survival in the HALAVEN ® group 13.1 months compared to 10.7 months in the control group. At one year, 54% of the patients were alive in the HALAVEN ® group compared to 44% in the control group. This statistically significant benefit was also seen in the overall response rates. We now have another agent with a distinct survival advantage for heavily pretreated metastatic breast cancer patients. J Clin Oncol 28:18s, 2010 (suppl; abstr CRA1004)