Androgen Receptor Modulation Optimized for Response-Splice Variant: A Phase 3, Randomized Trial of Galeterone Versus Enzalutamide in Androgen Receptor Splice Variant-7-expressing Metastatic Castration-resistant Prostate Cancer.

BACKGROUND: Detection of androgen receptor (AR) splice variant-7 (AR-V7) messenger RNA (mRNA) in circulating tumor cells (CTCs) is associated with a suboptimal response to abiraterone and enzalutamide in metastatic castration-resistant prostate cancer (mCRPC). Galeterone inhibits CYP17 and AR, and induces AR protein degradation. We hypothesized that galeterone would be clinically superior to enzalutamide in AR-V7-positive (AR-V7+) mCRPC. OBJECTIVE: To screen and characterize AR-V7+ mCRPC, and evaluate galeterone compared with enzalutamide. DESIGN, SETTING, AND PARTICIPANTS: This was a multicenter randomized phase 3 trial; enzalutamide-, abiraterone-, and chemotherapy-naïve mCRPC patients had AR-V7 prescreening using a CTC-based mRNA assay. INTERVENTION: AR-V7+ patients were randomized (1:1) to open-label galeterone or enzalutamide; planned sample size was 148. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was radiographic progression-free survival (rPFS). Baseline AR-V7 status was correlated with patient characteristics. RESULTS AND LIMITATIONS: Overall, 953 men were prescreened for AR-V7; 323 (34%) had detectable CTCs, and 73/323 had AR-V7 mRNA. The AR-V7+ prevalence was 8% (73/953; 95% confidence interval [CI] 6-10%). AR-V7 was associated with indicators of advanced and high-volume disease at baseline, including higher prostate-specific antigen (PSA) level (p < 0.001), more bone metastases (p < 0.001), docetaxel for hormone-sensitive disease (p < 0.001), prior first-generation androgen deprivation therapy (p < 0.001), and shorter time from diagnosis to enrollment (p < 0.001). Of 73 eligible patients, 38 were randomized to galeterone (n=19) or enzalutamide (n=19); 35 dropped out before randomization. Owing to high censorship for the rPFS events, the data monitoring committee recommended early closure based on interim evidence that the primary endpoint would not be met. The PSA50 values were 2/16 (13%) and 8/19 (42%) for galeterone and enzalutamide respectively (proportion difference=-0.278, 95% CI -0.490 to 0.097). CONCLUSIONS: The prevalence of CTC mRNA AR-V7 in first-line mCRPC was 8% (95% CI 6-10%). AR-V7+ was associated with the characteristics of aggressive and advanced disease. These men had rapid disease progression. Development of galeterone will not be pursued. PATIENT SUMMARY: Of men with metastatic castration-resistant prostate cancer, 8% had the androgen receptor splice variant-7 (AR-V7) blood biomarker. The AR-V7+ patients had features of aggressive disease. Thirty-eight men were treated with either galeterone or enzalutamide; the trial was stopped early prior to determining efficacy because too many patients transitioned off the trial due to advancing cancer before having required radiographs.

Efficacy and safety of gemcitabine, oxaliplatin, and bevacizumab in advanced biliary-tract cancers and correlation of changes in 18-fluorodeoxyglucose PET with clinical outcome: a phase 2 study.

BACKGROUND: Previous phase 2 studies have shown antitumour activity with gemcitabine and oxaliplatin (GEMOX) in patients with advanced biliary-tract cancers (BTCs). In this phase 2 study, we assessed the efficacy and safety of combined bevacizumab with GEMOX (GEMOX-B) in patients with advanced BTCs, and investigated how changes in 18-fluorodeoxyglucose ([(18)F]FDG)-PET correlate with clinical outcome. METHODS: Patients with advanced measurable BTCs were given the following treatment on days 1 and 15 of a 28-day cycle: bevacizumab 10 mg/kg, followed by gemcitabine 1000 mg/m(2) (10 mg/m(2) per min) and oxaliplatin 85 mg/m(2) (2-h infusion). [(18)F]FDG-PET scans were obtained at baseline and after completion of the second cycle. The primary endpoint was progression-free survival (PFS). Efficacy and safety analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00361231. FINDINGS: 35 patients were enrolled and evaluable for efficacy and toxicity. Median PFS was 7.0 months (95% CI 5.3-10.3), and PFS at 6 months was 63% (47-79), which was below the targeted rate of 70%. Grade 3-4 toxic effects included neutropenia (n=7), raised alanine aminotransferase concentrations (n=5), peripheral neuropathy (n=5), and hypertension (n=5). [(18)F]FDG-PET scans showed a significant decrease in maximum standardised uptake value (SUV(max)) after two cycles of treatment (5.72 [SD 2.01] at baseline; 3.73 [SD 1.88] after two cycles; p<0.0001). These changes were more pronounced in patients with partial response or stable disease than those with progressive disease (24 patients, -2.80 [SD 1.95] vs five patients, 1.41 [SD 3.13]; p=0.009). Change in SUV(max) was a significant predictor of PFS (HR 1.35, 1.14-1.60, p=0.0006) and overall survival (1.25, 1.05-1.50, p=0.01). INTERPRETATION: GEMOX-B showed antitumour activity with tolerable safety in patients with advanced BTCs. Decreases in SUV(max) on [(18)F]FDG-PET scans after treatment were associated with disease control and increases in PFS and overall survival. FUNDING: Genentech Oncology and Sanofi-Aventis.

Early antiangiogenic activity of bevacizumab evaluated by computed tomography perfusion scan in patients with advanced hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a highly vascularized tumor with a poor prognosis. In a phase II study that combined bevacizumab with gemcitabine and oxaliplatin in advanced HCC, we examined computed tomography perfusion (CTp) scan parameters as surrogate markers of angiogenesis after bevacizumab administration. METHODS: HCC patients received bevacizumab alone i.v. at 10 mg/kg on day 1 during cycle 1. CTp scanning was performed at baseline and days 10-12 to assess changes in tissue blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface area product (PS). RESULTS: Compared with baseline, a significant decrease in the estimated tumor perfusion parameters including BF, BV, and PS and an increase in MTT were seen on days 10-12 following bevacizumab administration alone. Patients with progressive disease had lower baseline MTT values and a higher percent increase following bevacizumab administration than those with stable disease or partial responses. CONCLUSIONS: Bevacizumab induced a significant decrease in tumor BF, BV, and PS and an increase in MTT by CTp scan in HCC. Baseline and percent change in MTT following bevacizumab administration correlated with clinical outcome, whereas BF, BV, and PS did not.

Phase 2 study of cetuximab in patients with advanced hepatocellular carcinoma.

BACKGROUND: Epidermal growth factor receptor (EGFR) and ligand expression is frequently seen in hepatocellular carcinoma (HCC). A phase 2 study was performed with cetuximab, a chimeric monoclonal antibody that binds specifically to EGFR, in patients with advanced HCC. METHODS: Eligibility criteria included unresectable or metastatic measurable HCC, an Eastern Cooperative Oncology Group performance status

Phase II study of gemcitabine and oxaliplatin in combination with bevacizumab in patients with advanced hepatocellular carcinoma.

PURPOSE: Hepatocellular carcinoma (HCC) is a vascular tumor with poor prognosis. Given the reported activity of gemcitabine and oxaliplatin (GEMOX) in HCC and the potential benefits of targeting the vascular endothelial growth factor pathway with bevacizumab (B), a phase II study of GEMOX-B was undertaken to define efficacy and toxicity profiles in HCC patients. PATIENTS AND METHODS: Eligible patients had pathologically proven measurable unresectable or metastatic HCC. For cycle 1 (14 days), bevacizumab 10 mg/kg was administered alone intravenously on day 1. For cycle 2 and beyond (28 days/cycle), bevacizumab 10 mg/kg was administered on days 1 and 15, gemcitabine 1,000 mg/m2 was administered as a dose rate infusion at 10 mg/m2/min followed by oxaliplatin at 85 mg/m2 on days 2 and 16. RESULTS: Thirty-three patients were enrolled and 30 patients were assessable for efficacy. The objective response rate was 20%, and 27% of patients had stable disease. Median overall survival was 9.6 months (95% CI, 8.0 months to not available) and median progression-free survival (PFS) was 5.3 months (95% CI, 3.7 to 8.7 months); the PFS rate at 3 and 6 months was 70% (95% CI, 54% to 85%) and 48% (95% CI, 31% to 65%), respectively. The most common treatment-related grade 3 to 4 toxicities included leukopenia/neutropenia, transient elevation of aminotransferases, hypertension, and fatigue. CONCLUSION: GEMOX-B could be safely administered with close monitoring and had moderate antitumor activity for patients with advanced HCC. The high 6-month PFS rate is encouraging, and this regimen is worthy of further investigation.