Bruce J. Roth

Eligibility and Response Guidelines for Phase II Clinical Trials in Androgen-Independent Prostate Cancer: Recommendations From the Prostate-Specific Antigen Working Group

PURPOSE Prostate-specific antigen (PSA) is a glycoprotein that is found almost exclusively in normal and neoplastic prostate cells. For patients with metastatic disease, changes in PSA will often antedate changes in bone scan. Furthermore, many but not all investigators have observed an association between a decline in PSA levels of 50% or greater and survival. Since the majority of phase II clinical trials for patients with androgen-independent prostate cancer (AIPC) have used PSA as a marker, we believed it was important for investigators to agree on definitions and values for a minimum set of parameters for eligibility and PSA declines and to develop a common approach to outcome analysis and reporting. We held a consensus conference with 26 leading investigators in the field of AIPC to define these parameters. RESULT We defined four patient groups: (1) progressive measurable disease, (2) progressive bone metastasis, (3) stable metastases and a rising PSA, and (4) rising PSA and no other evidence of metastatic disease. The purpose of determining the number of patients whose PSA level drops in a phase II trial of AIPC is to guide the selection of agents for further testing and phase III trials. We propose that investigators report at a minimum a PSA decline of at least 50% and this must be confirmed by a second PSA value 4 or more weeks later. Patients may not demonstrate clinical or radiographic evidence of disease progression during this time period. Some investigators may want to report additional measures of PSA changes (ie, 75% decline, 90% decline). Response duration and the time to PSA progression may also be important clinical end point. CONCLUSION Through this consensus conference, we believe we have developed practical guidelines for using PSA as a measurement of outcome. Furthermore, the use of common standards is important as we determine which agents should progress to randomized trials which will use survival as an end point.

Randomized study of cyclophosphamide, doxorubicin, and vincristine versus etoposide and cisplatin versus alternation of these two regimens in extensive small-cell lung cancer: a phase III trial of the Southeastern Cancer Study Group.

PURPOSE The trial was undertaken to determine (1) the relative efficacy/toxicity of two commonly used combination chemotherapy regimens in patients with extensive small-cell lung cancer (SCLC) and (2) whether the rapid alternation of these two regimens could provide superior therapeutic results compared with either regimen alone. PATIENTS AND METHODS In this phase III trial, 437 eligible patients were stratified by performance status (PS) and sex and were randomly assigned to receive either 12 weeks of cisplatin and etoposide (EP); 18 weeks of cyclophosphamide, doxorubicin, and vincristine (CAV); or 18 weeks of alternation of these two regimens (CAV/EP). RESULTS There were no significant differences in treatment outcome for EP, CAV, or CAV/EP in terms of response rate (61%, 51%, 59%, respectively), complete response rate (10%, 7%, 7%, respectively), or median survival (8.6 months, 8.3 months, 8.1 months, respectively), with a non-statistically significant trend toward a longer median time to progression with alternating therapy (4.3 months, 4.0 months, 5.2 months, respectively). Crossover second-line chemotherapy given at progression produced low response rates and short survival, regardless of the regimen used. Myelosuppression was the dose-limiting toxicity for all patients, although the pattern and severity differed among the treatment arms. CONCLUSIONS The combination regimens EP and CAV can be considered equivalently effective induction therapies in extensive SCLC, and these two regimens are, to some degree, crossresistant. Alternating therapy provides no therapeutic advantage compared with the use of either of these regimens alone and should not be considered as standard treatment in this clinical setting.

Cabozantinib versus Everolimus in Advanced Renal-Cell Carcinoma

BACKGROUND Cabozantinib is an oral, small-molecule tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor (VEGFR) as well as MET and AXL, each of which has been implicated in the pathobiology of metastatic renal-cell carcinoma or in the development of resistance to antiangiogenic drugs. This randomized, open-label, phase 3 trial evaluated the efficacy of cabozantinib, as compared with everolimus, in patients with renal-cell carcinoma that had progressed after VEGFR-targeted therapy. METHODS We randomly assigned 658 patients to receive cabozantinib at a dose of 60 mg daily or everolimus at a dose of 10 mg daily. The primary end point was progression-free survival. Secondary efficacy end points were overall survival and objective response rate. RESULTS Median progression-free survival was 7.4 months with cabozantinib and 3.8 months with everolimus. The rate of progression or death was 42% lower with cabozantinib than with everolimus (hazard ratio, 0.58; 95% confidence interval [CI] 0.45 to 0.75; P<0.001). The objective response rate was 21% with cabozantinib and 5% with everolimus (P<0.001). A planned interim analysis showed that overall survival was longer with cabozantinib than with everolimus (hazard ratio for death, 0.67; 95% CI, 0.51 to 0.89; P=0.005) but did not cross the significance boundary for the interim analysis. Adverse events were managed with dose reductions; doses were reduced in 60% of the patients who received cabozantinib and in 25% of those who received everolimus. Discontinuation of study treatment owing to adverse events occurred in 9% of the patients who received cabozantinib and in 10% of those who received everolimus. CONCLUSIONS Progression-free survival was longer with cabozantinib than with everolimus among patients with renal-cell carcinoma that had progressed after VEGFR-targeted therapy. (Funded by Exelixis; METEOR ClinicalTrials.gov number, NCT01865747.).

Phase II study of single-agent gemcitabine in previously untreated patients with metastatic urothelial cancer.

PURPOSE To determine the activity of single-agent gemcitabine in previously untreated patients with metastatic transitional cell cancer. METHODS Forty patients with measurable disease and a Karnofsky performance status > or = 60% were enrolled at five institutions between March 1994 and October 1995. Treatment consisted of gemcitabine (1,200 mg/m2) administered weekly times three on a 4-week cycle. One patient was ineligible for response evaluation because pathology review showed a metastatic melanoma. Responses were confirmed by all investigators and an independent radiologist and were maintained for at least 4 weeks. RESULTS There were four complete and seven partial responses, for an overall response rate of 28%. Responses were seen at all sites, including liver. Median progression-free and overall survival times were 20 and 54 weeks, respectively. Toxicity was mild, with only two grade 4 toxicities. Twenty-five percent of patients experienced grade 3 neutropenia or thrombocytopenia that was rapidly reversible. CONCLUSION Gemcitabine exhibits significant activity in metastatic transitional cell cancer with minimal toxicity, but survival remains short. Trials of gemcitabine in combination with other active agents are thus suggested.

Significant activity of paclitaxel in advanced transitional-cell carcinoma of the urothelium: a phase II trial of the Eastern Cooperative Oncology Group.

PURPOSE To assess the efficacy and toxicity of single-agent paclitaxel as first-line chemotherapy in patients with locally advanced or metastatic transitional-cell carcinoma of the urothelium. PATIENTS AND METHODS Twenty-six eligible patients were enrolled onto this cooperative group study and treated with paclitaxel at a dosage of 250 mg/m2 by 24-hour continuous infusion every 21 days until progression or patient intolerance. All patients received recombinant human granulocyte colony-stimulating factor (rhG-CSF) at 5 micrograms/kg/d for at least 10 days during each cycle. RESULTS Eleven of 26 patients (42%; 95% confidence interval [CI], 23% to 63%) demonstrated an objective response, with seven achieving a complete clinical response (CR) (27%; 95% CI, 12% to 48%) and four (15%) a partial response (PR). The median duration of response in the 11 responders is 7+ months (range, 4 to 17), with five responders (four CRs, one PR) remaining progression-free at 5, 6, 10, 12, and 16 months from the start of therapy. The estimated median survival duration for all patients is 8.4 months. Hematologic toxicity consisted of anemia (12% grade 3) and granulocytopenia (4% grade 3, 19% grade 4), with two patients developing granulocytopenic fevers. Nonhematologic toxicity included grade 3 mucositis in 11%, grade 3 neuropathy in 11%, and grade 4 diarrhea in 4%. CONCLUSION Single-agent paclitaxel at this dosage and schedule is one of the most active single agents in previously untreated patients with advanced urothelial carcinoma, and is well tolerated by this patient population when given with hematopoetic growth factor support.

Dose-intensive chemotherapy in refractory germ cell cancer--a phase I/II trial of high-dose carboplatin and etoposide with autologous bone marrow transplantation.

Between September 1986 and March 1988, 33 patients with refractory germ cell cancer were entered on a phase I/II trial of two courses of high-dose carboplatin plus etoposide with autologous bone marrow support. All patients had extensive prior treatment and had either cisplatin-refractory disease (67%) defined as progression within 4 weeks of the last cisplatin dose or failed at least two cisplatin-based regimens (35%) including a cisplatin-ifosfamide salvage regimen. Patients received a fixed total dose of etoposide of 1,200 mg/m2 with each cycle. The carboplatin dose ranged from 900 mg/m2 to 2,000 mg/m2. Twenty of the 33 patients received the second cycle of therapy. Despite extensive prior therapy with cisplatin, neurotoxicity, nephrotoxicity, or hearing impairment with high-dose carboplatin and etoposide was unusual. The most common nonhematologic toxicity was moderate enterocolitis. The hematologic toxicity of this regimen was substantial at each dose level. All 53 courses were accompanied by granulocytopenic fevers. Seven of the 33 patients (21%) died from treatment. All of these deaths occurred during the granulocyte nadir, and five were related to documented sepsis. Overall, 14 of 32 patients (44%) evaluable for response obtained an objective response, including eight complete remissions. Four patients remain in complete remission, with three patients being continuously free of disease in excess of 1 year. Eight responders (including four complete remissions) had progressed while receiving cisplatin. We conclude that carboplatin and etoposide can be administered in combination at high dosages and this regimen may have curative potential for patients with germ cell tumors resistant to conventional-dose cisplatin-based therapies.

Phase I, Pharmacokinetic, and Pharmacodynamic Study of AMG 479, a Fully Human Monoclonal Antibody to Insulin-Like Growth Factor Receptor 1

PURPOSE To determine the maximum-tolerated dose (MTD) and to assess the safety, pharmacokinetics, and evidence of antitumor activity of AMG 479, a fully human monoclonal antibody to insulin-like growth factor receptor 1 (IGF-1R). PATIENTS AND METHODS Patients with advanced solid malignancies or non-Hodgkins lymphoma received escalating doses of AMG 479 intravenously (IV) every 2 weeks (Q2W). Blood samples were assayed to determine pharmacokinetic parameters and IGF-1R occupancy on neutrophils; fluorodeoxyglucose-positron emission tomography scans were used to assess tumor metabolic effects. RESULTS Fifty-three patients received 312 infusions of AMG 479 Q2W. Overall, the most common grades 1 to 2 toxicities were fatigue, thrombocytopenia, fever, rash, chills, and anorexia. One dose-limiting toxicity (ie, grade 3 thrombocytopenia) occurred in a patient at 20 mg/kg during course 1; grade 3 thrombocytopenia (n = 8) and grade 3 transaminitis elevations (n = 1) also were reported but not in the escalation phase. The maximum-planned dose of 20 mg/kg was safely administered; thus, an MTD was not reached. High levels of neutrophil IGF-1R binding and increases from baseline in serum IGF-1 levels were observed in the 12- and 20-mg/kg cohorts. Tumor responses included one durable complete response (CR) and one unconfirmed partial response (PR) in two patients with Ewing/primitive neuroectodermal tumors and included one PR and one minor response in two patients with neuroendocrine tumors. The patients with Ewing/PNET who had a CR have remained disease free on therapy after 28 months. CONCLUSION AMG 479 can be administered safely at 20 mg/kg IV Q2W. The absence of severe toxicities, attainment of serum concentrations associated with high levels of IGF-1R binding on neutrophils, and provocative antitumor activity warrant additional studies of this agent.

Hematologic Neoplasia Associated with Primary Mediastinal Germ-Cell Tumors

Between September 1983 and December 1988, we observed 16 cases of hematologic neoplasia associated with mediastinal germ-cell tumors. Twenty-eight similar cases have been reported in the literature. A review of the clinical and cytogenetic details in these patients suggests that the hematologic neoplasia is not the result of cisplatin-based chemotherapy of the mediastinal germ-cell cancer. This syndrome was found only in patients with nonseminomatous mediastinal germ-cell tumors, particularly those with serologic or histologic evidence of yolk-sac elements. The two most common hematologic neoplasms seen in this syndrome were acute megakaryoblastic leukemia and malignant histiocytosis. Consistent cytogenetic abnormalities have not yet been identified, but the finding of the marker chromosome isochromosome (12p) in the mediastinal germ-cell tumor and associated leukemic blasts in one patient suggests that these tumors may arise from a common progenitor cell.

Cabozantinib versus everolimus in advanced renal cell carcinoma (METEOR): final results from a randomised, open-label, phase 3 trial

BACKGROUND Cabozantinib is an oral inhibitor of tyrosine kinases including MET, VEGFR, and AXL. The randomised phase 3 METEOR trial compared the efficacy and safety of cabozantinib versus the mTOR inhibitor everolimus in patients with advanced renal cell carcinoma who progressed after previous VEGFR tyrosine-kinase inhibitor treatment. Here, we report the final overall survival results from this study based on an unplanned second interim analysis. METHODS In this open-label, randomised phase 3 trial, we randomly assigned (1:1) patients aged 18 years and older with advanced or metastatic clear-cell renal cell carcinoma, measurable disease, and previous treatment with one or more VEGFR tyrosine-kinase inhibitors to receive 60 mg cabozantinib once a day or 10 mg everolimus once a day. Randomisation was done with an interactive voice and web response system. Stratification factors were Memorial Sloan Kettering Cancer Center risk group and the number of previous treatments with VEGFR tyrosine-kinase inhibitors. The primary endpoint was progression-free survival as assessed by an independent radiology review committee in the first 375 randomly assigned patients and has been previously reported. Secondary endpoints were overall survival and objective response in all randomly assigned patients assessed by intention-to-treat. Safety was assessed per protocol in all patients who received at least one dose of study drug. The study is closed for enrolment but treatment and follow-up of patients is ongoing for long-term safety evaluation. This trial is registered with ClinicalTrials.gov, number NCT01865747. FINDINGS Between Aug 8, 2013, and Nov 24, 2014, 658 patients were randomly assigned to receive cabozantinib (n=330) or everolimus (n=328). The median duration of follow-up for overall survival and safety was 18·7 months (IQR 16·1-21·1) in the cabozantinib group and 18·8 months (16·0-21·2) in the everolimus group. Median overall survival was 21·4 months (95% CI 18·7-not estimable) with cabozantinib and 16·5 months (14·7-18·8) with everolimus (hazard ratio [HR] 0·66 [95% CI 0·53-0·83]; p=0·00026). Cabozantinib treatment also resulted in improved progression-free survival (HR 0·51 [95% CI 0·41-0·62]; p<0·0001) and objective response (17% [13-22] with cabozantinib vs 3% [2-6] with everolimus; p<0·0001) per independent radiology review among all randomised patients. The most common grade 3 or 4 adverse events were hypertension (49 [15%] in the cabozantinib group vs 12 [4%] in the everolimus group), diarrhoea (43 [13%] vs 7 [2%]), fatigue (36 [11%] vs 24 [7%]), palmar-plantar erythrodysaesthesia syndrome (27 [8%] vs 3 [1%]), anaemia (19 [6%] vs 53 [17%]), hyperglycaemia (3 [1%] vs 16 [5%]), and hypomagnesaemia (16 [5%] vs none). Serious adverse events grade 3 or worse occurred in 130 (39%) patients in the cabozantinib group and in 129 (40%) in the everolimus group. One treatment-related death occurred in the cabozantinib group (death; not otherwise specified) and two occurred in the everolimus group (one aspergillus infection and one pneumonia aspiration). INTERPRETATION Treatment with cabozantinib increased overall survival, delayed disease progression, and improved the objective response compared with everolimus. Based on these results, cabozantinib should be considered as a new standard-of-care treatment option for previously treated patients with advanced renal cell carcinoma. Patients should be monitored for adverse events that might require dose modifications. FUNDING Exelixis Inc.

Vinblastine Versus Vinblastine Plus Oral Estramustine Phosphate for Patients With Hormone-Refractory Prostate Cancer: A Hoosier Oncology Group and Fox Chase Network Phase III Trial

PURPOSE To compare vinblastine versus the combination of vinblastine plus estramustine as treatment for patients with hormone-refractory prostate cancer (HRPC). PATIENTS AND METHODS A total of 201 patients with metastatic prostate cancer, progressive after hormonal therapy and antiandrogen withdrawal (if prior antiandrogen treatment), were randomized to receive vinblastine (V) 4 mg/m(2) by intravenous bolus weekly for 6 weeks followed by 2 weeks off, either alone or together with estramustine phosphate (EM-V) 600 mg/m(2) PO days 1 through 42, repeated every 8 weeks. Of 193 eligible patients, 98 received V, and 95 received EM-V. RESULTS Overall survival trended in favor of EM-V but was not significantly different as determined by Kaplan-Meier analysis (P =.08). Median survival was 11.9 months for EM-V and 9.2 months for V. EM-V was superior to V for secondary end points of time to progression (P <. 001, stratified log rank test; median 3.7 v 2.2 months, respectively) and for proportion of patients with >/= 50% prostate-specific antigen (PSA) decline sustained for at least 3 monthly measurements (25.2% v 3.2%, respectively; P <.0001). Granulocytopenia was significantly less for EM-V compared with V (grade 2, 3, and 4 = 7%, 7%, and 1% v 27%, 18% and 9%, respectively; P <.0001); however, grade 2 or worse nausea (26% v 7%, respectively; P =.0002) and extremity edema (22% v 8%, respectively; P =.005) were more frequent for EM-V. CONCLUSION Although overall survival was not significantly greater for the combination, EM-V was superior to V for time to progression and PSA improvement. These results encourage further study of estramustine-based antimicrotubule drug combinations in HRPC.