The efficacy and safety of sunitinib given on an individualised schedule as first-line therapy for metastatic renal cell carcinoma: A phase 2 clinical trial.

BACKGROUND: Sunitinib is administered on a rigid schedule that may not be optimal for all patients. We hypothesised that toxicity-driven dose and schedule changes would optimise drug exposure and outcome for each patient. MATERIALS AND METHODS: In a phase 2 trial, 117 patients with metastatic clear cell renal cell cancer were started on sunitinib 50 mg/day with the aim to treat for 28 days. Treatment breaks were reduced to 7 days. Sunitinib dose and the number of days on therapy were individualised based on toxicity aiming for ≤ grade II toxicity with dose escalation in patients with minimal toxicity. The null hypothesis for the primary end-point was a progression-free survival (PFS) of 8.5 months based on a study with similar eligibility criteria. RESULTS: The null hypothesis was rejected (p < 0.001) with a median PFS of 12.5 months (95% confidence interval [CI]: 9.6-16.5). The median overall survival was 38.5 months (95% CI: 28.3-not reached). The objective response rate (46.1%) and stable disease rate (38.5%) translated into a clinical benefit for 84.6% of patients with no decline in quality of life scores during therapy. Fewer patients were dose reduced (26.5% vs. 50%) or discontinued due to toxicity (7.7 vs. 18-20%) compared to standard sunitinib dosing, and 20 (18.4%) patients were dose escalated to 62.5 mg (12) and 75 mg (8) with a wide individual variation in the optimal dose and treatment duration. CONCLUSIONS: Individualised sunitinib therapy is feasible, safe and an effective method to manage toxicity with one of the best efficacy seen for oral vascular endothelial growth factor inhibitors in metastatic renal cell carcinoma. CLINICALTRIALS. GOV IDENTIFIER: NCT01499121.

Enzalutamide in metastatic prostate cancer before chemotherapy.

BACKGROUND: Enzalutamide is an oral androgen-receptor inhibitor that prolongs survival in men with metastatic castration-resistant prostate cancer in whom the disease has progressed after chemotherapy. New treatment options are needed for patients with metastatic prostate cancer who have not received chemotherapy, in whom the disease has progressed despite androgen-deprivation therapy. METHODS: In this double-blind, phase 3 study, we randomly assigned 1717 patients to receive either enzalutamide (at a dose of 160 mg) or placebo once daily. The coprimary end points were radiographic progression-free survival and overall survival. RESULTS: The study was stopped after a planned interim analysis, conducted when 540 deaths had been reported, showed a benefit of the active treatment. The rate of radiographic progression-free survival at 12 months was 65% among patients treated with enzalutamide, as compared with 14% among patients receiving placebo (81% risk reduction; hazard ratio in the enzalutamide group, 0.19; 95% confidence interval [CI], 0.15 to 0.23; P<0.001). A total of 626 patients (72%) in the enzalutamide group, as compared with 532 patients (63%) in the placebo group, were alive at the data-cutoff date (29% reduction in the risk of death; hazard ratio, 0.71; 95% CI, 0.60 to 0.84; P<0.001). The benefit of enzalutamide was shown with respect to all secondary end points, including the time until the initiation of cytotoxic chemotherapy (hazard ratio, 0.35), the time until the first skeletal-related event (hazard ratio, 0.72), a complete or partial soft-tissue response (59% vs. 5%), the time until prostate-specific antigen (PSA) progression (hazard ratio, 0.17), and a rate of decline of at least 50% in PSA (78% vs. 3%) (P<0.001 for all comparisons). Fatigue and hypertension were the most common clinically relevant adverse events associated with enzalutamide treatment. CONCLUSIONS: Enzalutamide significantly decreased the risk of radiographic progression and death and delayed the initiation of chemotherapy in men with metastatic prostate cancer. (Funded by Medivation and Astellas Pharma; PREVAIL ClinicalTrials.gov number, NCT01212991.).

Intermittent versus continuous androgen deprivation in prostate cancer.

BACKGROUND: Castration resistance occurs in most patients with metastatic hormone-sensitive prostate cancer who are receiving androgen-deprivation therapy. Replacing androgens before progression of the disease is hypothesized to prolong androgen dependence. METHODS: Men with newly diagnosed, metastatic, hormone-sensitive prostate cancer, a performance status of 0 to 2, and a prostate-specific antigen (PSA) level of 5 ng per milliliter or higher received a luteinizing hormone-releasing hormone analogue and an antiandrogen agent for 7 months. We then randomly assigned patients in whom the PSA level fell to 4 ng per milliliter or lower to continuous or intermittent androgen deprivation, with patients stratified according to prior or no prior hormonal therapy, performance status, and extent of disease (minimal or extensive). The coprimary objectives were to assess whether intermittent therapy was noninferior to continuous therapy with respect to survival, with a one-sided test with an upper boundary of the hazard ratio of 1.20, and whether quality of life differed between the groups 3 months after randomization. RESULTS: A total of 3040 patients were enrolled, of whom 1535 were included in the analysis: 765 randomly assigned to continuous androgen deprivation and 770 assigned to intermittent androgen deprivation. The median follow-up period was 9.8 years. Median survival was 5.8 years in the continuous-therapy group and 5.1 years in the intermittent-therapy group (hazard ratio for death with intermittent therapy, 1.10; 90% confidence interval, 0.99 to 1.23). Intermittent therapy was associated with better erectile function and mental health (P<0.001 and P=0.003, respectively) at month 3 but not thereafter. There were no significant differences between the groups in the number of treatment-related high-grade adverse events. CONCLUSIONS: Our findings were statistically inconclusive. In patients with metastatic hormone-sensitive prostate cancer, the confidence interval for survival exceeded the upper boundary for noninferiority, suggesting that we cannot rule out a 20% greater risk of death with intermittent therapy than with continuous therapy, but too few events occurred to rule out significant inferiority of intermittent therapy. Intermittent therapy resulted in small improvements in quality of life. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT00002651.).

Randomized, open-label phase III trial of docetaxel plus high-dose calcitriol versus docetaxel plus prednisone for patients with castration-resistant prostate cancer.

PURPOSE: To compare the efficacy and safety of docetaxel plus high-dose calcitriol (DN-101) to docetaxel plus prednisone in an open-label phase III trial. PATIENTS AND METHODS: Nine hundred fifty-three men with metastatic castration-resistant prostate cancer (CRPC) were randomly assigned to Androgen-Independent Prostate Cancer Study of Calcitriol Enhancing Taxotere (ASCENT; 45 µg DN-101, 36 mg/m(2) docetaxel, and 24 mg dexamethasone weekly for 3 of every 4 weeks) or control (5 mg prednisone twice daily with 75 mg/m(2) docetaxel and 24 mg dexamethasone every 3 weeks) arms. The primary end point was overall survival (OS), assessed by the Kaplan-Meier method. RESULTS: At an interim analysis, more deaths were noted in the ASCENT arm, and the trial was halted. The median-follow-up for patients alive at last assessment was 11.7 months. Median OS was 17.8 months (95% CI, 16.0 to 19.5) in the ASCENT arm and 20.2 months (95% CI, 18.8 to 23.0) in the control arm (log-rank P = .002). Survival remained inferior after adjusting for baseline variables (hazard ratio, 1.33; P = .019). The two arms were similar in rates of total and serious adverse events. The most frequent adverse events were GI (reported in 75% of patients), and blood and lymphatic disorders (48%). Docetaxel toxicity leading to dose modification was more frequent in the ASCENT (31%) than in the control arm (15%). CONCLUSION: ASCENT treatment was associated with shorter survival than the control. This difference might be due to either weekly docetaxel dosing, which, in a prior study, showed a trend toward inferior survival compared with an every-3-weeks regimen, or DN-101 therapy.

A population-based study examining the effect of tyrosine kinase inhibitors on survival in metastatic renal cell carcinoma in Alberta and the role of nephrectomy prior to treatment.

BACKGROUND: We performed a retrospective population-based study to assess the impact of tyrosine kinase inhibitors (TKIs) on overall survival (OS) in patients treated for metastatic renal cell carcinoma (mRCC) in Alberta, Canada and to assess the impact of nephrectomy on OS in patients treated with TKIs. METHODS: We identified 134 patients who began taking a TKI between December 2003 and June 2007 for mRCC in Alberta. We compared survival in this group to that in an earlier cohort of 141 patients treated with interferon-alpha (IFN-alpha) between May 1995 and March 2003. We used the Kaplan-Meier method to determine OS, and we used a Cox proportional hazards model to determine hazard ratios (HRs) and confidence intervals (CIs). We performed multivariate analysis to assess the impact of neprhectomy on OS. RESULTS: Of the 134 patients treated with TKIs, 81 received treatment in the first-line setting, whereas 53 received treatment after prior IFN-alpha therapy. All 141 patients from the IFN-alpha cohort received treatment in the first-line setting. Patients treated with TKIs had an improved OS compared with the IFN-alpha cohort (HR 0.61, 95% CI 0.45-0.83, p = 0.001). The median OS was 18 months in the TKI group and 10 months in the IFN-alpha group. The benefit of TKIs was confined to favourable and intermediate risk groups according to the Memorial Sloan-Kettering Cancer Center prognostic model. Prior nephrectomy was associated with improved OS in the TKI cohort, independent of other prognostic factors. CONCLUSION: Tyrosine kinase inhibitors improve OS compared with IFN-alpha in mRCC. In patients treated with TKIs, prior nephrectomy is associated with improved survival independent of other prognostic variables.

Associations between comorbidity, and overall survival and bladder cancer specific survival after radical cystectomy: results from the Alberta Urology Institute Radical Cystectomy database.

PURPOSE: We determined the associations between comorbidity, and overall survival and bladder cancer specific survival after radical cystectomy. MATERIALS AND METHODS: The Alberta Urology Institute Radical Cystectomy database is an ongoing multi-institutional computerized database containing data on all adult patients with a diagnosis of primary bladder cancer treated with radical cystectomy in Edmonton, Canada from April 1994 forward. The current study is an analysis of consecutive database patients treated between April 1994 and September 2007. Comorbidity information was obtained through a medical record review using the Adult Comorbidity Evaluation 27 instrument. The outcome measures were overall survival and bladder cancer specific survival. Cox proportional regression analysis was used to determine the associations between comorbidity, and overall survival and bladder cancer specific survival. RESULTS: Of the database patients 160 (34%), 225 (48%) and 83 (18%) had no/mild comorbidity, moderate comorbidity and severe comorbidity, respectively. Compared to patients with no or mild comorbidity, multivariate Cox proportional regression analyses that included age, adjuvant chemotherapy, surgeon procedure volume, pathological T stage, pathological lymph node status, total number of lymph nodes removed, surgical margin status and lymphovascular invasion showed that increased comorbidity was independently associated with overall survival (moderate HR 1.59, 95% CI 1.16-2.18, p = 0.004; severe HR 1.83, 95% CI 1.22-2.72, p = 0.003) and bladder cancer specific survival (moderate HR 1.50, 95% CI 1.04-2.15, p = 0.028; severe HR 1.65, 95% CI 1.04-2.62, p = 0.034). CONCLUSIONS: Increased comorbidity was independently associated with an increased risk of overall mortality and bladder cancer specific mortality after radical cystectomy.

A prospective study of the determinants of exercise in bladder cancer survivors using the Theory of Planned Behavior.

GOALS OF WORK: Although exercise has gained recognition as an effective supportive care intervention for cancer survivors, exercise participation rates are low. The present study examined the determinants of exercise in bladder cancer survivors using the Theory of Planned Behavior (TPB). PATIENTS AND METHODS: Bladder cancer survivors (N = 397) residing in Alberta, Canada completed a mailed questionnaire at baseline that assessed demographic, medical, behavioral, and social cognitive variables and a second questionnaire 3 months later that assessed exercise. Multiple regression was the primary analysis. MAIN RESULTS: Adjuvant therapy (r = -0.10, p = 0.021), cancer invasiveness (r = -0.10, p = 0.051), and age (r = -0.11, p = 0.037) were all negatively associated with exercise. Intention (beta = 0.25, p < 0.001), perceived behavioral control (beta = 0.18, p = 0.001), and planning (beta = 0.12, p = 0.018) explained 20.9% of the variance in exercise over a 3-month period. Perceived behavioral control (beta = 0.32, p < 0.001), affective attitude (beta = 0.18, p = 0.002), instrumental attitude (beta = 0.15, p = 0.025) and descriptive norm (beta = 0.10, p = 0.032) explained 39.1% of the variability in exercise intention. Constructs from the TPB mediated the associations between adjuvant therapy, cancer invasiveness, age, and exercise. Age and adjuvant therapy also moderated some of the associations within the TPB. CONCLUSIONS: Some medical and demographic variables predict exercise behavior in bladder cancer survivors, but these associations are mediated by the TPB. Interventions based on the TPB may be effective for promoting exercise in this cancer survivor population.

Intermittent chemotherapy in patients with metastatic androgen-independent prostate cancer: results from ASCENT, a double-blinded, randomized comparison of high-dose calcitriol plus docetaxel with placebo plus docetaxel.

BACKGROUND: Survival in patients with metastatic, chemotherapy-naive, androgen-independent prostate cancer (AIPC) is improved with 10 to 12 cycles of docetaxel-containing chemotherapy but further management is undefined. In the current study, the authors examined retreatment with the same regimen after a treatment holiday. METHODS: Patients treated with docetaxel at a dose of 36 mg/m(2) plus either high-dose calcitriol (DN-101; 45 mug) or placebo administered weekly for 3 of every 4 weeks could suspend treatment if their serum prostate-specific antigen (PSA) level was reduced >or=50% and reached a level or=50% and was >or=2 ng/mL or when there was other evidence of disease progression. The study was not powered to compare treatment holiday outcomes between the 2 arms. RESULTS: A total of 250 patients were randomized 1:1. Overall, 18% of patients (20% in the high-dose calcitriol group and 16% in the placebo group) entered the intermittent chemotherapy arm. The median duration of the first chemotherapy holiday was 18 weeks (range, 4%70 weeks). On resumption of treatment after the first holiday, 45.5% of evaluable patients responded with a >or=50% reduction in serum PSA from their postholiday baseline, 45.5% met the criteria for stable PSA for at least 12 weeks, and 9.1% of patients developed disease progression. CONCLUSIONS: To the authors' knowledge, the current study is the first report of intermittent chemotherapy in patients with AIPC who were prospectively tested in a large multi-institutional trial. This strategy results in a clinically significant duration of chemotherapy holidays and can be offered to a minority of patients. At the time of retreatment, the majority of patients again respond to treatment or their PSA levels stabilized. Additional studies of intermittent chemotherapy are needed to better characterize the optimal patient population and the optimal approach.

Double-blinded randomized study of high-dose calcitriol plus docetaxel compared with placebo plus docetaxel in androgen-independent prostate cancer: a report from the ASCENT Investigators.

PURPOSE: To compare the safety and activity of DN-101, a new high-dose oral formulation of calcitriol designed for cancer therapy, and docetaxel with placebo and docetaxel. PATIENTS AND METHODS: Patients with progressive metastatic androgen-independent prostate cancer and adequate organ function received weekly docetaxel 36 mg/m2 intravenously for 3 weeks of a 4-week cycle combined with either 45 microg DN-101 or placebo taken orally 1 day before docetaxel. The primary end point was prostate-specific antigen (PSA) response within 6 months of enrollment, defined as a 50% reduction confirmed at least 4 weeks later. RESULTS: Two hundred fifty patients were randomly assigned. Baseline characteristics were similar in both arms. Within 6 months, PSA responses were seen in 58% in DN-101 patients and 49% in placebo patients (P = .16). Overall, PSA response rates were 63% (DN-101) and 52% (placebo), P = .07. Patients in the DN-101 group had a hazard ratio for death of 0.67 (P = .04) in a multivariate analysis that included baseline hemoglobin and performance status. Median survival has not been reached for the DN-101 arm and is estimated to be 24.5 months using the hazard ratio, compared with 16.4 months for placebo. Grade 3/4 adverse events occurred in 58% of DN-101 patients and in 70% of placebo-treated patients (P = .07). Most common grade 3/4 toxicities for DN-101 versus placebo were neutropenia (10% v 8%), fatigue (8% v 16%), infection (8% v 13%), and hyperglycemia (6% v 12%). CONCLUSION: This study suggests that DN-101 treatment was associated with improved survival, but this will require confirmation because survival was not a primary end point. The addition of weekly DN-101 did not increase the toxicity of weekly docetaxel.

Prostate-specific antigen doubling time is associated with survival in men with hormone-refractory prostate cancer.

OBJECTIVES: Men with metastatic hormone-refractory prostate cancer (HRPC) form a heterogeneous population with a wide range of symptoms and variable survival. Patient selection is critical in determining which patients will receive the most benefit from aggressive chemotherapy. The prostate-specific antigen (PSA) doubling time (PSADT) has been shown to be a surrogate for survival in earlier stages of prostate cancer, but its utility as a predictor in HRPC is unknown. METHODS: A retrospective chart review of 224 patients with HRPC treated from 1998 to 2002 was performed. Eligible patients had HRPC and evidence of metastatic disease. The PSADT at HRPC diagnosis was calculated, and the optimal PSADT stratification was obtained using the log-rank chi-square statistic. Kaplan-Meier curves were used to estimate overall survival between the groups. RESULTS: During the follow-up period, 80% of patients died, 93% of prostate cancer. Overall, the median survival from diagnosis of HRPC was 15.1 months (range 0.5 to 90.5). The optimal PSADT stratification for survival was 70 days. Patients with a PSADT of 70 days or less survived 11 months compared with 19 months for those with a PSADT of more than 70 days [relative risk (RR) 1.79, P <0.0001]. CONCLUSIONS: PSADT serves as an independent prognostic marker for survival in patients with metastatic HRPC. Men with a PSADT of 70 days or less had a significantly shorter survival time compared with men with a PSADT of more than 70 days. Inclusion of PSADT with other clinical data could help clinicians select men at high risk of early mortality who may most benefit from aggressive treatment regimens, such as docetaxel-based regimens.

High dose calcitriol may reduce thrombosis in cancer patients.

The incidence of venous and arterial thrombosis in a placebo-controlled randomised trial of DN-101 (high dose calcitriol) with docetaxel versus docetaxel was compared. Of the 13 thrombotic events observed in the 250 patients enroled in this study, two occurred in DN-101 and 11 in placebo-treated patients (P = 0.01). This difference remained significant after adjustment for baseline history of thrombosis, atrial fibrillation and use of anti-thrombotic agents. In vitro and vitamin D receptor (VDR) knockout mouse studies predict that nanomolar concentrations of calcitriol may act as an antithrombotic agent. We report the first clinical observation that supports this hypothesis in humans.

Compliance and outcome of patients with stage 1 non-seminomatous germ cell tumors (NSGCT) managed with surveillance programs in seven Canadian centres.

OBJECTIVE: We evaluate the impact of surveillance programs on the outcome of men with clinical stage 1 NSGCT following orchidectomy. PATIENTS AND METHODS: A retrospective review of 197 patients with a minimum of 2 years follow-up at seven cancer centres was conducted. Histological characteristics of the primary tumor were recorded for each patient. Surveillance protocols consisted of clinical assessments, chest X-rays, serum beta HCG (bHCG), alpha feto-protein (aFP), and abdominopelvic CT. All clinic visits and test completions were tracked. In accordance with each centre's specific surveillance protocol, patient compliance was defined as missing no more than two assessments/year. RESULTS: Overall 5 year survival was 100%. With a median follow-up of 54 months (range: 11-164 months), the relapse rate at 5 years was 29%. The median time to relapse was 6 months (range: 2-135 months). Ninety percent of relapses occurred within 18 months and only two patients relapsed after 5 years. On univariate analysis, only the presence of lymphovascular invasion was predictive of relapse. The first indicator of relapse was: CT alone, 36%; elevated bHCG or aFP, 29%; CXR, 10%; or clinical exam, 7%. Either CT, tumor markers, or CXR detected 90% of all relapses. Although differences in the frequency of assessments between the centres existed, no significant differences occurred in rates of relapse or survival (p>0.07). The mean rate of compliance with clinic visit (which included CXR and tumor markers) was 78% (range: 68.4-94.2%). The mean rate of compliance with CT scanning, was 64.3% (range: 32.2-100%). In the centre with the protocol requiring the least frequent visits, the rates of compliance were observed to be highest. CONCLUSIONS: Surveillance remains an effective means of managing stage 1 NSGCT despite variability in protocols and in patients compliance. An abnormal CT was the most frequent identifier of disease relapse, and in combination with tumor markers and CXR, 90% of relapses were detected within 2 years of orchiectomy. Modifications of surveillance protocols to less frequent assessments may be possible and should be subject to prospective evaluation.

Three independent factors predicted adherence in a randomized controlled trial of resistance exercise training among prostate cancer survivors.

OBJECTIVE: To examine predictors of adherence in a randomized controlled trial of resistance exercise training (RET) in prostate cancer survivors receiving androgen deprivation therapy. STUDY DESIGN AND SETTING: A randomized controlled trial conducted at fitness centers in Ottawa and Edmonton, Canada. Prostate cancer survivors (n=155) completed measures of social cognitive variables, quality of life (QOL), behavior, and fitness before being randomized to either an exercise (n=82) or control (n=73) group. The exercise group was asked to perform supervised RET three times per week for 12 weeks. RESULTS: The exercise group attended 28.2 of the 36 (78.3%) RET sessions. Univariate analyses revealed eight different significant (Ps <.05) predictors of exercise adherence including exercise stage of change, intention, age, QOL, fatigue, subjective norm, leg-press test, and perceived behavioral control. A multivariate analysis indicated that there were three independent predictors of adherence that explained 20.4% of the variance: exercise stage of change (beta=0.26; P=.013), age (beta=-0.22; P=.037), and intention (beta=0.19; P=.073). CONCLUSION: Exercise adherence in the trial was very good but not optimal. Adherence was predicted by variables from many different categories including social cognitive, QOL, behavioral, fitness, and demographic. These findings may have important implications for maximizing adherence during clinical trials of exercise in prostate cancer survivors.

Resistance exercise in men receiving androgen deprivation therapy for prostate cancer.

PURPOSE: Androgen deprivation therapy is a common treatment in men with prostate cancer that may cause fatigue, functional decline, increased body fatness, and loss of lean body tissue. These physical changes can negatively affect health-related quality of life. Resistance exercise may help to counter some of these side effects by reducing fatigue, elevating mood, building muscle mass, and reducing body fat. METHODS: In a two-site study, 155 men with prostate cancer who were scheduled to receive androgen deprivation therapy for at least 3 months after recruitment were randomly assigned to an intervention group that participated in a resistance exercise program three times per week for 12 weeks (82 men) or to a waiting list control group (73 men). The primary outcomes were fatigue and disease-specific quality of life as assessed by self-reported questionnaires after 12 weeks. Secondary outcomes were muscular fitness and body composition. RESULTS: Men assigned to resistance exercise had less interference from fatigue on activities of daily living (P =.002) and higher quality of life (P =.001) than men in the control group. Men in the intervention group demonstrated higher levels of upper body (P =.009) and lower body (P <.001) muscular fitness than men in the control group. The 12-week resistance exercise intervention did not improve body composition as measured by changes in body weight, body mass index, waist circumference, or subcutaneous skinfolds. CONCLUSION: Resistance exercise reduces fatigue and improves quality of life and muscular fitness in men with prostate cancer receiving androgen deprivation therapy. This form of exercise can be an important component of supportive care for these patients.

A randomized phase II and pharmacokinetic study of the antisense oligonucleotides ISIS 3521 and ISIS 5132 in patients with hormone-refractory prostate cancer.

PURPOSE: Protein kinase C (PKC)-alpha and Raf-1 are important elements of proliferative signal transduction pathways in both normal and malignant cells. Abrogation of either Raf-1 or PKC-alpha function can both inhibit cellular proliferation and induce apoptosis in several experimental cancer models including prostate cancer cell lines. ISIS 3521 and ISIS 5132 are antisense phosphorothioate oligonucleotides that inhibit PKC-alpha and Raf-1 expression, respectively, and induce a broad spectrum of antiproliferative and antitumor effects in several human tumor cell lines. In Phase I evaluation both ISIS 3521 and ISIS 5132 could be safely administered on 21-day i.v. infusion schedules and demonstrated preliminary evidence of antitumor activity. On the basis of these findings, a randomized Phase II study of ISIS 3521 and ISIS 5132 was performed in two comparable cohorts of patients who had chemotherapy-naïve, hormone-refractory prostate cancer (HRPC). PATIENTS AND METHODS: Patients with documented evidence of metastatic HRPC and a prostate-specific antigen (PSA) value > or =20 ng/ml were randomized to receive treatment with either ISIS 3521 or ISIS 5132 as a continuous i.v. infusion for 21 days repeated every 4 weeks. Patients were stratified according to the presence or absence of bidimensionally measurable disease at the time of randomization. The principal endpoints included PSA response, objective response in patients with bidimensionally measurable disease, and treatment failure defined as new or worsening symptoms; a fall in performance status of 2 levels; new or objective progression of disease; or a rise in PSA for 12 weeks without symptom improvement. Plasma samples were collected to assess individual steady-state concentrations and to relate this pharmacokinetic parameter to observed toxicities and responses. RESULTS: Thirty-one patients were randomized in this study; 15 patients received 43 courses of ISIS 3521 and 16 patients received 48 courses of ISIS 5132. The most common toxicities observed were mild to moderate (grade 1 or 2) fatigue and lethargy in 21% and 56% of patients treated with ISIS 3521 and ISIS 5132, respectively. Although no objective or PSA responses were observed in any patient treated with ISIS 3521 or ISIS 5132, persistent stable disease was observed in 3 patients for 5 or more months, and in 5 patients the PSA values did not rise >25% for 120 days or longer. CONCLUSIONS: The antisense oligonucleotides ISIS 3521 and ISIS 5132, at these doses and on this schedule, do not possess clinically significant single-agent antitumor activity in HRPC. Protracted stable disease in some patients may indicate a cytostatic effect. Additional work is required to define the optimal role of PKC-alpha or Raf-1 inhibition in the treatment of HRPC.

Safety and efficacy of the multidrug-resistance inhibitor biricodar (VX-710) with concurrent doxorubicin in patients with anthracycline-resistant advanced soft tissue sarcoma.

PURPOSE: Incel (biricodar, VX-710) restores drug sensitivity to P-glycoprotein and multidrug resistance-associated protein-1-expressing cells. This Phase I/II study evaluated the safety/tolerability, pharmacokinetics, and efficacy of VX-710 plus doxorubicin in patients with inoperable, locally advanced or metastatic, anthracycline-resistant/refractory, soft tissue sarcoma. EXPERIMENTAL DESIGN: In Phase I, i.v. bolus doxorubicin at 60, 75, or 67.5 mg/m(2) was administered 8 h after initiation of a 72-h continuous i.v. (CIV) infusion of VX-710 (120 mg/m(2)/h) to cohorts of patients to establish a maximum tolerated dose. For efficacy evaluations in Phase II, eligible patients had inoperable, locally advanced or metastatic, anthracycline-resistant/refractory soft tissue sarcoma; < or =225 mg/m(2) cumulative prior doxorubicin; and adequate hematological, liver, and kidney function. Cycles were repeated every 3 weeks. RESULTS: Fourteen patients were enrolled in Phase I. Myelosuppression was the dose-limiting toxicity with 75 and then 67.5 mg/m(2) doxorubicin, and the maximum tolerated dose was established at 60 mg/m(2) with VX-710, 120 mg/m(2)/h, 72-h CIV. VX-710 had no apparent effect on doxorubicin pharmacokinetics. Twenty-nine patients enrolled in Phase II were treated with VX-710, 120 mg/m(2)/h 72-h CIV, and 60 mg/m(2) doxorubicin. Among 26 evaluable patients, minimal activity was noted among 11 patients with gastrointestinal stromal tumors (GISTs); however, in 15 patients with anthracycline-resistant sarcomas of other histologies, 2 achieved partial responses and 7 patients had disease stabilization with an overall median progression-free interval of 3.4 months. CONCLUSION: Anthracycline resistance in GISTs appears to be independent of P-glycoprotein or multidrug resistance-associated protein-1 resistance mechanisms. However, the combination of VX-710 and doxorubicin resulted in objective responses or disease stabilization in patients with strictly defined anthracycline-refractory non-GIST sarcomas, which warrants further evaluation.