Bevacizumab Cohort Research Articles

Survival in elderly glioblastoma patients treated with bevacizumab-based regimens in the United States.

The efficacy of bevacizumab (BEV) in elderly patients with glioblastoma remains unclear. We evaluated the effect of BEV on survival in this patient population using the Survival, Epidemiology, and End Results (SEER)-Medicare database. This retrospective, cohort study analyzed SEER-Medicare data for patients (aged ≥66 years) diagnosed with glioblastoma from 2006 to 2011. Two cohorts were constructed: one comprised patients who had received BEV (BEV cohort); the other comprised patients who had received any anticancer treatment other than BEV (NBEV cohort). The primary analysis used a multivariate Cox proportional hazards model to compare overall survival in the BEV and NBEV cohorts with initiation of BEV as a time-dependent variable, adjusting for potential confounders (age, gender, Charlson comorbidity index, region, race, radiotherapy after initial surgery, and diagnosis of coronary artery disease). Sensitivity analyses were conducted using landmark survival, propensity score modeling, and the impact of poor Karnofsky Performance Status. We identified 2603 patients (BEV, n = 597; NBEV, n = 2006). In the BEV cohort, most patients were Caucasian males and were younger with fewer comorbidities and more initial resections. In the primary analysis, the BEV cohort showed a lower risk of death compared with the NBEV cohort (hazard ratio, 0.80; 95% confidence interval, 0.72-0.89; P < .01). The survival benefit of BEV appeared independent of the number of temozolomide cycles or frontline treatment with radiotherapy and temozolomide. BEV exposure was associated with a lower risk of death, providing evidence that there might be a potential benefit of BEV in elderly patients with glioblastoma.

Polymorphisms in adipokine-related genes to predict treatment outcomes in patients (pts) with metastatic colorectal cancer (mCRC) treated with bevacizumab-based chemotherapy.

600 Background: The molecular effects of obesity are mediated by alterations in the levels of adipokines, which are produced mainly by adipose tissue. Adipokines have multiple effects, including insulin sensitivity, cell proliferation, inflammation, and angiogenesis. We previously reported that single-nucleotide polymorphisms (SNPs) in obesity-related genes were associated with the recurrence probability of CRC treated with 5-FU based adjuvant chemotherapy. This study aimed to evaluate whether SNPs in adipokine-related genes may predict clinical outcomes in bevacizumab treated mCRC pts. Methods: Genomic DNA was obtained from mCRC pts receiving bevacizumab plus FOLFIRI as first-line treatment and analyzed by using PCR-based direct sequencing. Eleven functional SNPs in 7 genes ( LEP, LEPR, ADIPOQ, ADIPOR1, RETN, TNFa and NAMPT) were tested in 291 pts in FIRE3 trial bevacizumab cohort (NCT00433927). Main characteristics were the following: male/female = 193/98; median age = 65; High BMI pts (BMI ≥ 25 Kg/m2)/low BMI pts (BMI &lt; 25 Kg/m2) = 162/129; median PFS = 10.1 months; median OS = 24.2 months, median follow-up time = 40.8 months. Results: LEPR rs1137100 G/G variants (n = 24) showed worse PFS than any A variants (n = 246) in univariate (10.4 months (M) vs. 9.2 M, HR = 1.75, 95%CI = 1.12-2.74, P = 0.011) and multivariate analyses (HR = 1.75, 95%CI = 1.11-2.74, P = 0.016). NAMPT rs61330082 T/T (n = 24) showed worse PFS than any C variants (n = 243) in multivariate analysis (HR = 1.65, 95% = 1.02-2.67, P = 0.042). RETN rs1862513 C/C (n = 23) showed worse OS than any G variants (n = 246) in univariate analysis (14.1 m vs. 25.1 M, HR = 1.65, 95%CI = 1.04-2.60, P = 0.029). In subgroup analyses of high BMI pts, the prognostic effect of LEPR rs1137100 G/G and RETN rs1862513 C/C was confirmed and no association was observed among low BMI pts. Conclusions: Our study showed for the first time that genetic variations in adipokine-related genes are associated with prognosis of mCRC pts treated with bevacizumab based chemotherapy.

Myoinositol as a Biomarker in Recurrent Glioblastoma Treated with Bevacizumab: A 1H-Magnetic Resonance Spectroscopy Study.

BackgroundAntiangiogenic treatment of glioblastomas with Bevacizumab lacks predictive markers. Myoinositol (MI) is an organic osmolyte, with intracellular concentration changes depending on the extracellular osmolality. Since Bevacizumab markedly reduces tumor edema and influences the tumor microenvironment, we investigated whether the MI concentration in the tumor changes during therapy.MethodsWe used 1H-magnetic resonance spectroscopy to measure the MI concentrations in the tumor and contralateral control tissue of 39 prospectively recruited patients with recurrent glioblastomas before and 8–12 weeks after starting therapy. 30 patients received Bevacizumab and 9 patients were treated with CCNU/VM26 as control. We performed a survival analysis to evaluate MI as a predictive biomarker for Bevacizumab therapy.ResultsMI concentrations increased significantly during Bevacizumab therapy in tumor (p < .001) and control tissue (p = .001), but not during CCNU/VM26 treatment. For the Bevacizumab cohort, higher MI concentrations in the control tissue at baseline (p = .021) and higher differences between control and tumor tissue (delta MI, p = .011) were associated with longer survival. A Kaplan-Meier analysis showed a median OS of 164 days for patients with a deltaMI < 1,817 mmol/l and 275 days for patients with a deltaMI > 1,817 mmol/l. No differences were observed for the relative changes or the post treatment concentrations. Additionally calculated creatine concentrations showed no differences in between subgroups or between pre and post treatment measurements.ConclusionOur data suggest that recurrent glioblastoma shows a strong metabolic reaction to Bevacizumab. Further, our results support the hypothesis that MI might be a marker for early tumor cell invasion. Pre-therapeutic MI concentrations are predictive of overall survival in patients with recurrent glioblastoma treated with Bevacizumab.

Toxicity profile of bevacizumab in the UK Neurofibromatosis type 2 cohort.

Bevacizumab is considered an established part of the treatment strategies available for schwannomas in patients with Neurofibromatosis type 2 (NF2). In the UK, it is available through NHS National Specialized Commissioning to NF2 patients with a rapidly growing target schwannoma. Regrowth of the tumour on suspension of treatment is often observed resulting in prolonged periods of exposure to bevacizumab to control the disease. Hypertension and proteinuria are common events with bevacizumab use and there are concerns with regards to the long-term risks of prolonged treatment. Dosing, demographic and adverse event (CTCAE 4.03) data from the UK NF2 bevacizumab cohort are reviewed with particular consideration of renal and cardiovascular complications. Eighty patients (48 male:32 female), median age 24.5 years (range 11-66 years), were followed for a median of 32.7 months (range 12.0-60.2 months). The most common adverse events were fatigue, hypertension and infection. A total of 19/80 patients (24 %) had either a grade 2 or grade 3 hypertension event and 14/80 patients (17.5 %) had proteinuria. Of 36 patients followed for 36 months, 78 % were free from hypertension and 86 % were free of proteinuria. Logistic regression modeling identified age and induction dosing regime to be independent predictors of development of hypertension with dose of 7.5mg/kg 3 weekly and age >30years having higher rates of hypertension. Proteinuria persisted in one of three patients after cessation of bevacizumab. One patient developed congestive heart failure and the details of this case are described. Further work is needed to determine optimal dosing regimes to limit toxicity without impacting on efficacy.

Efficacy and Safety of Onartuzumab in Combination With First-Line Bevacizumab- or Pemetrexed-Based Chemotherapy Regimens in Advanced Non-Squamous Non–Small-Cell Lung Cancer

BackgroundOnartuzumab is a monovalent monoclonal antibody that binds with the extracellular domain of the MET receptor. Given the role of MET in non–small-cell lung cancer (NSCLC), we investigated whether onartuzumab added to first-line chemotherapy efficacy in non-squamous NSCLC. MethodsPatients with untreated stage IIIB/IV non-squamous NSCLC, stratified by MET diagnostic status, were randomized to receive onartuzumab (15 mg/kg intravenously every 3 weeks) or placebo in combination with either paclitaxel/platinum/bevacizumab (bevacizumab cohort), or in combination with platinum/pemetrexed (pemetrexed cohort) with maintenance bevacizumab or pemetrexed and onartuzumab/placebo as appropriate. Co-primary endpoints of this phase II study were progression-free survival (PFS) in all patients and in MET+ patients (2+/3+), defined by the Ventana immunohistochemistry assay; secondary endpoints included overall survival (OS), objective response rate (ORR), safety, and pharmacokinetics. ResultsEfficacy data were available for 139 and 120 patients in the bevacizumab and pemetrexed cohorts, respectively. No benefit was seen in the PFS endpoint in the intent-to treat population of either cohort, but was numerically worse in the onartuzumab arm of the MET+ subgroup of the bevacizumab cohort. The onartuzumab and placebo arms had similar ORR and OS results in both cohorts. A higher incidence of some adverse events was observed with onartuzumab versus placebo, including peripheral edema (30% vs. 3%, bevacizumab cohort; 48% vs. 14%, pemetrexed cohort) and venous thromboembolic events (bevacizumab cohort only, 15% vs. 6%). ConclusionOnartuzumab does not appear to provide any additional clinical benefit when given in combination with current first-line standard-of-care chemotherapy for non-squamous NSCLC.

TWIST1 Polymorphisms Predict Survival in Patients with Metastatic Colorectal Cancer Receiving First-Line Bevacizumab plus Oxaliplatin-Based Chemotherapy.

The epithelial-mesenchymal transition (EMT) is an important mechanism of resistance to angiogenesis inhibition. The ability of EMT pathway genetic variants to predict the efficacy of antiangiogenic therapy is unknown. We analyzed associations between functional SNPs in EMT-related genes and outcomes in metastatic colorectal cancer (mCRC) patients undergoing first-line bevacizumab-based chemotherapy. A total of 220 mCRC patients were included in this study: 143 patients treated with first-line bevacizumab-based chemotherapy (bevacizumab cohort) and 77 patients treated with cetuximab-based chemotherapy (cetuximab cohort). SNPs in TWIST1 (rs2285682, rs2285681), ZEB1 (rs10826943, rs2839658), SNAIL (rs1543442, rs4647958), and E-cadherin (rs16260) genes were analyzed by PCR-based direct sequencing. Patients carrying a TWIST1 rs2285682 G allele had a significantly longer median progression-free survival (PFS) of 18.1 months and overall survival (OS) of 44.1 months compared with those with the T/T genotype, who had a median PFS of 13.3 months (HR, 0.57; P = 0.003) and OS of 29.2 months (HR, 0.53; P = 0.001) in the bevacizumab cohort. In multivariate analysis, associations between TWIST1 rs2285682 and PFS and OS remained significant. Among women, the G allele of TWIST1 rs2285682 (PFS HR, 0.39; P = 0.007; OS HR, 0.30; P = 0.001) and TWIST1 rs2285681 (PFS HR, 0.27; P < 0.001; OS HR, 0.25; P < 0.001) was associated with improved survival. No significant associations were found in the cetuximab cohort. Our findings suggest that TWIST1 polymorphisms are associated with survival in mCRC patients treated with first-line bevacizumab-based chemotherapy and may serve as clinically useful biomarkers for antiangiogenic therapy. Mol Cancer Ther; 15(6); 1405-11. ©2016 AACR.

Endothelin-1 genetic polymorphism as predictive marker for bevacizumab in metastatic breast cancer.

Biomarkers for bevacizumab efficacy in metastatic breast cancer (MBC) are of urgent need. The genetic variability of genes involved in angiogenesis could explain the interpatient variability of drug effects. For this biomarker study DNA was extracted from tumor blocks or blood samples of patients with human epidermal growth factor receptor 2 (HER2)-negative MBC treated with bevacizumab in combination with chemotherapy (bevacizumab cohort, 163 patients) or chemotherapy only (control cohort, 105 patients). We assessed the correlation of 10 single-nucleotide polymorphisms (SNPs) in genes modulating angiogenesis (vascular endothelial growth factor-A (VEGF-A), VEGF receptor 1 (VEGFR-1), serine threonine kinase 39 (STK39)) or hypertension (endothelin-1 and uromodulin) with outcome and toxicity. In the bevacizumab cohort, the SNP rs5370-TT in endothelin-1 (EDN1) showed a significantly shorter median overall survival (OS, 6.3 vs 21.3 months; hazard ratio (HR) 2.89, 95% confidence interval (CI) 1.34-6.26; log-rank P=0.0069) and a trend toward worse median progression-free survival (3.5 vs 7.9 months; HR 2.05, 95% CI 0.96-4.39; log-rank P=0.065) compared with the alternate genotypes combined. Similarly, patients harboring the VEGF-936 (rs3025039) TT alleles showed a significantly shorter median OS than patients with VEGF-936 CC or CT (14.9 vs 21.3 months; HR 2.37, 95% CI 1.09-5.13; P=0.0286). In multivariate analysis including important clinical parameters like disease-free survival (DFS), adjuvant chemotherapy, ECOG (Eastern Cooperative Oncology Group) performance score, histologic subtype, grade, hormone receptor status, visceral metastases and treatment line, only the association of rs5370 (EDN1) with OS was still statistically significant (P=0.012). In the control cohort, no association of the EDN1 genotype with outcome was seen, suggesting a predictive value for bevacizumab. In conclusion, the SNP rs5370 in endothelin-1 could help identifying patients who unlikely gain any benefit from bevacizumab.

Ranibizumab Versus Bevacizumab for Neovascular Age-Related Macular Degeneration With an Incomplete Posterior Vitreous Detachment.

The aim of this study was to compare the effects of ranibizumab to those of bevacizumab during the treatment of neovascular age-related macular degeneration (AMD) with an incomplete posterior vitreous detachment. A retrospective chart review. A retrospective chart review was performed on treatment-naive neovascular AMD subjects with an incomplete posterior vitreous detachment treated with either ranibizumab or bevacizumab over a 12-month period. One hundred thirty subjects were analyzed. There were 49 subjects determined to have vitreous attachment to the fovea. Subjects with vitreous attachment to the fovea required a significantly greater number of injections during the study interval compared with those without (10.2 ± 0.75 vs 7.8 ± 0.62) (P < 0.0001). In subjects with vitreous attachment to the fovea, the ranibizumab cohort had a greater improvement in visual acuity (0.18 ± 0.1 vs 0.04 ± 0.11 logMAR) (P = 0.0176) and a greater reduction in macular thickness (93.4 ± 32.2 μm vs 30.3 ± 28.3 μm) (P = 0.0064) compared with the bevacizumab cohort. Neovascular AMD patients with vitreous attachment to the fovea may have better visual and anatomic outcomes when treated with ranibizumab compared with bevacizumab.

Valganciclovir and bevacizumab for recurrent glioblastoma: A single-institution experience.

Prolonged treatment with adjuvant valganciclovir has been shown in one retrospective study to exert a significant effect on overall survival (OS) in newly diagnosed patients with glioblastoma multiforme (GBM). However, studies evaluating the effectiveness of valganciclovir in the treatment of recurrent GBM have not been performed. We evaluated the effect of valganciclovir in the recurrent setting in combination with bevacizumab therapy. A retrospective analysis was performed on patients treated for recurrent GBM with off-label valganciclovir and bevacizumab at Vanderbilt University. We identified 13 patients who received valganciclovir plus bevacizumab at some point during their treatment, 8 of whom were started on valganciclovir and bevacizumab concurrently upon first recurrence, whereas 5 had valganciclovir added to their bevacizumab regimen prior to a second recurrence. of these patients, 12 were pathologically confirmed to have GBM, and 1 patient was diagnosed with gliosarcoma. We also identified an institutional cohort of 50 patients who had not been exposed to valganciclovir, but were treated with bevacizumab for first recurrence. The progression-free survival (PFS) at 6 months (PF6) and median OS (mOS) in the valganciclovir plus bevacizumab group was 62% and 13.1 months, respectively, for all 13 patients, and 50% and 11.3 months, respectively, for the 8 concurrently treated patients. In the institutional bevacizumab cohort, the PF6 and mOS were 34% and 8.7 months, respectively. In this retrospective analysis, valganciclovir in combination with bevacizumab exhibited a trend toward improved survival in patients with recurrent GBM. However, given the small sample size and the retrospective nature of this study, a larger prospective study is required to confirm these results.

A phase I trial of pegylated liposomal doxorubicin (PLD), carboplatin, bevacizumab and veliparib in recurrent, platinum-sensitive ovarian, primary peritoneal, and fallopian tube cancer: An NRG Oncology/Gynecologic Oncology Group study

ObjectiveTo determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of veliparib combined with PLD and carboplatin (CD) in patients with recurrent, platinum-sensitive epithelial ovarian cancer. To determine the tolerability at the MTD combined with bevacizumab. MethodsPatients received PLD (30mg/m2, IV) and carboplatin (AUC 5, IV) on day 1 with veliparib on days 1–7 (intermittent) or days 1–28 (continuous). Standard 3+3 design was used in the dose escalation phase with DLTs based on the first cycle. Once the MTDs were determined, cohorts of 6 patients were enrolled to each regimen with bevacizumab (10mg/kg on days 1 and 15) to assess feasibility. DLTs were based on the first 4cycles of treatment in the bevacizumab cohorts. ResultsIn the dose-escalation phase, 27 patients were treated at 3 dose levels with DLTs noted in 6 patients including grade 4 thrombocytopenia (n=4), and prolonged neutropenia >7days (n=3). At the MTD of veliparib (80mg p.o. b.i.d. for both dosing arms), myelosuppression was the DLT. At MTD, 12 additional patients were treated with bevacizumab with 9 patients experiencing DLTs including grade 4 thrombocytopenia (n=4), prolonged neutropenia >7days (n=1), grade 3 hypertension (n=5), and grade 5 sepsis (n=1). ConclusionsThe MTD of veliparib combined with CD is 80mg p.o. b.i.d. in women with recurrent, platinum-sensitive ovarian cancer. With bevacizumab, DLTs were noted in 9 out of 12 patients. Lower doses of veliparib will need to be considered when given in combination with platinum-based therapies.

Association of compounded bevacizumab with postinjection endophthalmitis.

Current draft guidelines set forth by the US Food and Drug Administration for compounded or repackaged medications would greatly limit the availability and use of bevacizumab by ophthalmologists across the country. Little evidence beyond highly publicized case reports exists for or against the need for additional regulation of compounded bevacizumab. To determine whether the distribution of bevacizumab through compounding pharmacies increases the risk for endophthalmitis compared with the distribution of single-use vials of ranibizumab from the manufacturer. A retrospective cohort study using medical claims data from ambulatory care centers across the United States that were submitted to a large, national US insurer. Cohorts were created using information on 530 382 intravitreal injections administered from January 1, 2005, through December 31, 2012. Any individual from this data set who received an intravitreal injection of bevacizumab or ranibizumab (n=383 810) and had at least 6 months of data before and 1 month after the injection was eligible. After exclusions (any previous diagnosis of endophthalmitis, multiple injected drugs given on the index day, or intraocular surgery within 15 days of the injection or between the injection and a diagnosis of endophthalmitis), our analysis involved 383 810 intravitreal injections given to 58 612 patients. Data collection and analysis occurred from February 16 through April 7, 2015. The odds of developing endophthalmitis after an intravitreal injection of bevacizumab compared with ranibizumab. In total, 296 565 injections of bevacizumab were given to 51 116 patients and 87 245 injections of ranibizumab were given to 7496 patients. We found 71 cases of endophthalmitis (49 in the bevacizumab cohort and 22 in the ranibizumab cohort) for an endophthalmitis rate of 0.017% (95% CI, 0.012%-0.021%; 1 case per 6061 injections) for bevacizumab and 0.025% (95% CI, 0.015%-0.036%; 1 case per 3968 injections) for ranibizumab. After controlling for age, race, sex, injection-related diagnosis, and year of injection, we found no significant association with development of endophthalmitis after a bevacizumab injection compared with ranibizumab (odds ratio, 0.66 [95% CI, 0.39-1.09]; P = .11). The results of this study suggest bevacizumab as currently used across the United States does not increase the risk for endophthalmitis; therefore, additional regulations on the use of repackaged bevacizumab may be unnecessary.

Relative cerebral blood volume is a potential predictive imaging biomarker of bevacizumab efficacy in recurrent glioblastoma.

To analyze the relevance of dynamic susceptibility-weighted contrast-enhanced MRI (DSC-MRI) derived relative cerebral blood volume (rCBV) analysis for predicting response to bevacizumab (BEV) in patients with recurrent glioblastoma (rGB). A total of 127 patients diagnosed with rGB receiving either bevacizumab (71 patients, BEV cohort) or alkylating chemotherapy (56 patients, non-BEV cohort) underwent conventional anatomic MRI and DSC-MRI at baseline and at first follow-up after treatment initiation. The mean rCBV of the contrast-enhancing tumor (cT1) as well as cT1 and fluid-attenuated inversion recovery (FLAIR) volumes at both time points were correlated with progression-free survival (PFS) and overall survival (OS) using Cox proportional hazard models, logistic regression, and the log-rank test. Baseline rCBV was associated with both PFS (hazard ratio [HR] = 1.3; P < .01) and OS (HR = 1.3; P < .01) in the BEV cohort and predicted 6-month PFS in 82% and 12-month OS in 79% of patients, whereas it was not associated with PFS (HR = 1.0; P = .70) or OS (HR = 1.0; P = .47) in the non-BEV cohort. Corresponding median OS and PFS rates in the BEV cohort for patients with rCBV-values less than 3.92 (optimal threshold from receiver operating characteristic [ROC] analysis of 12-month OS data) were 14.2 and 6.0 months, as compared to 6.6 and 2.8 months for patients with rCBV-values greater than 3.92 (P < .01, respectively). cT1 and FLAIR volumes at first follow-up were significant predictors of 6-month PFS and 12-month OS in the BEV cohort but not in the non-BEV cohort. Corresponding volumes at baseline were not significant in any cohort. Pretreatment rCBV is a potential predictive imaging biomarker in BEV-treated rGB but not alkylating chemotherapy-treated rGB, which is superior to volumetric analysis of conventional anatomic MRI and predicts 6-month PFS and 12-month OS in 80% of BEV-treated patients.

A phase 1b, open-label study of trebananib plus bevacizumab or motesanib in patients with solid tumours

To examine the angiopoietin pathway inhibitor trebananib IV plus the anti-VEGF agents bevacizumab or motesanib in advanced solid tumours. In this open-label phase 1b study, patients received IV trebananib 3 mg kg-1 QW plus bevacizumab 15 mg kg-1 Q3W (cohort 1) or motesanib orally 75 mg (cohort 2); or trebananib 10 mg kg-1 plus bevacizumab 15 mg kg-1 (cohort 3) or motesanib 125 mg (cohort 4). If <33% of patients had dose-limiting toxicities (DLTs), dose escalation occurred. Endpoints were treatment-related adverse events (AEs) incidence and pharmacokinetics (primary); anti-trebananib antibodies, biomarkers, and tumour response (secondary). Thirty-six patients received ≥ 1 dose of trebananib (cohorts 1, 2, 3, 4; n = 6, 8, 19, 3). DLT of G3 intestinal perforation and G3 tumor haemorrhage occurred in cohorts 2 and 3, respectively (both n = 1). Across both trebananib plus bevacizumab cohorts, the most common AEs included fatigue (n = 8), diarrhoea (n =4), constipation (n = 3), nausea (n = 3), and epistaxis (n = 3). Three patients across those cohorts had grade ≥ 3 AEs. Across the trebananib plus motesanib cohorts, the most common AEs included hypertension (n = 4), diarrhoea (n = 4), nausea (n = 3), fatigue (n = 3), vomiting (n = 2), and decreased appetite (n = 2). Two patients had grade ≥ 3 AEs. Trebananib did not markedly affect motesanib pharmacokinetics. Across the trebananib plus bevacizumab cohorts, two patients had a partial response; 11 patients had stable disease lasting >6 months. Across the trebananib plus motesanib cohorts, one patient had a partial response; five patients had stable disease lasting >6 months. Trebananib IV 3 mg kg-1 or 10 mg kg-1 plus bevacizumab or motesanib in advanced solid tumours may be associated with less severe toxicities relative to those emerging when combining two anti-VEGF agents.

Corroboration of claims algorithm for second-line costs of metastatic colorectal cancer treatment with targeted agents

Objective:To refine a claims algorithm for identifying second-line systemic regimens for metastatic colorectal cancer (mCRC) based on clinical evidence and to compare costs during second-line treatment by targeted therapy administered.Methods:This retrospective analysis of a large US managed care database identified patients diagnosed with mCRC during 1 July 2007–30 June 2011. A claims-based algorithm was developed to identify patients with at least two lines of therapy (LOT) and the second LOT contained one targeted agent: bevacizumab or any anti-epidermal growth factor receptor (EGFR). Medical chart data from 92 patients were used to corroborate and refine the LOT algorithm. The positive predictive value (PPV) of the initial algorithm and refined algorithm for identification of second LOT are presented. The final algorithm was applied to claims data and two mutually exclusive second-line cohorts were examined: patients with bevacizumab- or cetuximab-containing regimens. Second-line healthcare costs were analyzed with generalized linear models adjusted for demographic and clinical characteristics.Results:The PPV increased from 50.0% (95% CI = 39.4–60.6) for the initial algorithm to 72.1% (95% CI = 59.2–82.9) for the final algorithm. Mean age in the cohorts (n = 569) was 61 years; 58% were men. Days of therapy were similar for the bevacizumab (n = 450) vs cetuximab (n = 119) cohorts, respectively: 131 vs 148 in first LOT and 123 (both cohorts) in second LOT (p ≥ 0.27). Total costs during second-line treatment in the bevacizumab cohort were lower by $12,318 (p = 0.02) and medical costs were lower by $13,809 (p = 0.01). Monthly total and medical costs were lower by $2728 (p = 0.03) and $3133 (p = 0.01), respectively. Results are based on commercially or Medicare-insured patients and may not be generalizable to Medicaid or uninsured patients.Conclusions:Corroboration of claim-based algorithms with medical chart data improved algorithm performance. Second-line total and medical costs were lower for mCRC patients treated with bevacizumab compared with cetuximab.

Neoadjuvant bevacizumab: Surgical complications of mastectomy with and without reconstruction.

1100 Background: Neoadjuvant therapy is commonly used in operable breast cancer. We prospectively evaluated the surgical complications in a cohort of patients who underwent mastectomy following neoadjuvant doxorubucin hydrochloride/cyclophosphamide/paclitaxel (AC/T) plus bevacizumab and compared the rate of complications to a matched cohort of neoadjuvant AC/T without bevacizumab. Methods: One hundred patients with HER2-negative breast cancer enrolled in a single-arm trial of neoadjuvant AC/T plus bevacizumab (cohort 1), 60 of these patients underwent mastectomy and were matched with 59 patients who received standard neoadjuvant AC/T (cohort 2) over a similar time period in the same healthcare system. All patients underwent mastectomy with or without reconstruction. Fisher’s exact tests were used to compare complication rates, with a p&lt;0.05 was considered significant. Results: Patients were matched well in terms of demographics. The overall complication rate was 33% in cohort 1 and 31% in cohort 2 (P-value=0.84; Table). In cohort 1, 7 of 23 (30%) patients who underwent immediate expander/implant reconstruction had complications, including 2 patients who had explantation of their reconstructions. In cohort 2, 0 of 8 (0%) had complications (p value=0.15). Conclusions: Nearly a third of patients undergoing neoadjuvant therapy with AC/T with or without bevacizumab developed a postoperative complication after mastectomy. The use of bevacizumab was not associated with a significant increase in surgical complications, although this is a non-randomized data with a small sample size. As larger data sets become available with the use of neoadjuvant bevacizumab with mastectomy, further refinement may be necessary. [Table: see text]

Maintenance single-agent bevacizumab or observation after first-line chemotherapy in patients with metastatic colorectal cancer: a multicenter retrospective study

The addition of bevacizumab to standard chemotherapy has improved progression-free survival (PFS) and overall survival (OS) in patients with metastatic colorectal cancer (mCRC) in both first- and second line treatment, but the role of maintenance bevacizumab remains controversial. The association of various clinical factor and survival was examined in this retrospective cohort analysis. The clinical data from 220 previously untreated patients with mCRC, not progressive at the end of standard chemotherapy plus bevacizumab, were collected and analyzed. Patients were classified into two subgroups: those given with maintenance bevacizumab: "maintenance bevacizumab cohort (n = 118; MB)", and those discontinuing bevacizumab as a result of physician's or patient's decision: "no maintenance bevacizumab cohort (n = 102; noMB)". The baseline factors were well balanced between the study subgroups. Median PFS and OS for the general population was 10 months (range 7-15) and 22.5 months (range 18-26), respectively. Median PFS was 13 and 8 months in the BM and noBM cohorts, respectively (p < 0.0001). In the multivariate analysis, maintenance therapy resulted independently associated with improved PFS (HR 1.73; p < 0.001), but only objective response (OR) after first-line chemotherapy was associated with improved OS. Maintenance chemotherapy cannot be considered a standard of care after induction chemotherapy for mCRC, because the optimal balance between efficacy and safety of maintenance therapy remains a significant challenge. The results of our retrospective study suggest that maintenance therapy with bevacizumab is a safe and valuable option, particularly in those patients achieving an objective response after first-line chemotherapy.

Phase II Clinical and Pharmacokinetic Study of Aflibercept in Patients with Previously Treated Metastatic Colorectal Cancer

Aflibercept is a recombinant fusion protein of the VEGF receptor (VEGFR) 1 and VEGFR2 extracellular domains. We assessed the safety and efficacy of aflibercept in patients with metastatic colorectal cancer (MCRC) who had received at least one prior palliative regimen. Seventy-five patients were enrolled onto this two-stage phase II trial in two cohorts, bevacizumab naïve (n = 24) and prior bevacizumab (n = 51). Aflibercept was administered at 4 mg/kg i.v. in two-week cycles. The primary endpoint was a combination of objective response rate and 16-week progression-free survival (PFS). In the bevacizumab-naïve cohort (n = 24), the best response was stable disease for 16 weeks or more in five of 24 patients. In the prior bevacizumab cohort (n = 50), one patient achieved a partial response and six patients had stable disease for 16 weeks or more. The median PFS in the bevacizumab-naïve and prior bevacizumab cohorts was two months [95% confidence interval (CI): 1.7-8.6 months] and 2.4 months (95% CI: 1.9-3.7 months), respectively. Median overall survival (OS) was 10.4 months (95% CI: 7.6-15.5) and 8.5 months (95% CI: 6.2-10.6), respectively. The most common grade 3 or higher treatment-related adverse events were hypertension, proteinuria, fatigue, and headache. Ten patients discontinued study treatment due to toxicity. Mean free to VEGF-bound aflibercept ratio was 1.82, suggesting that free aflibercept was present in sufficient amount to bind endogenous VEGF. Aflibercept showed limited single-agent activity in patients with pretreated MCRC with moderate toxicity. Further study of aflibercept with chemotherapy is ongoing.

Abstract 3491: Chromosome 14q loss leads to haploinssuficiency of HIF-1a and poor outcomes in metastatic clear cell renal cell carcinoma

Abstract Purpose – One of the current key dilemmas in the management of metastatic renal cell carcinoma (mRCC) is the manifestation of innate or acquired resistance to anti-angiogenic therapy. Currently there are no biomarkers of therapeutic efficacy for antiangiogenic agents in clear cell renal cell carcinoma (ccRCC). Loss of chromosomal arm 14q has been previously associated with poor outcomes in surgically treated patients. We evaluated the association between 14q loss and therapeutic resistance in metastatic ccRCC (mRCC) and explored the role of candidate effector genes on this chromosome. Experimental Design – DNA from archival FFPE tumor specimens from 56 mRCC patients treated with sorafenib or bevacizumab was analyzed with Affymetrix 250K Nsp SNP microarrays. We identified the presence of genomic imbalances focusing on the presence of 14q loss. We then evaluated candidate genes in chromosome 14 by qPCR and immunohistochemistry (IHC) in the bevacizumab treated cohort. Results – 14q loss showed a significant association with worse response (SDPD vs. CRPR) in bevacizumab cohort (Fisher's exact test, p=0.0473), and with shorter progression free survival (PFS) in the sorafenib cohort (p=0.0318). HIF1A mRNA expression was significantly reduced in specimens with loss of 14q and was associated with PFS in the bevacizumab treated cohort (p=0.045). HIF-1alpha protein expression was also reduced in samples with 14q loss. Conclusions – Our studies demonstrate an association between a specific chromosomal alteration (14q loss) and clinical outcome in patients with advanced renal cell carcinoma treated with antiangiogenic agents. Loss of 14q was also associated to changes in the expression of HIF1A. Low HIF1A expression was strongly correlated with shorter PFS. We hypothesize that loss of 14q could lead to an imbalance in HIF-1α/HIF-2α activity, leading to increased HIF-2α, which has been shown to improve tumor cell viability by upregulating various pro-survival pathways. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3491. doi:10.1158/1538-7445.AM2011-3491

Chromosome 14q imbalances and pathways associated with resistance to antiangiogenic therapy in clear cell renal cell carcinoma.

339 Background: Antiangiogenic agents are used to treat metastatic clear cell renal cell carcinoma (ccRCC). Currently there are no biomarkers of therapeutic efficacy for these agents. Hypoxia inducible factor (HIF) alpha ratios have been linked to phenotypically distinct ccRCC subpopulations. The HIF1 alpha gene is located on chromosome 14q. In this study, the goal was to determine whether chromosomal imbalances identified with SNP arrays are linked to HIF ratios, and to clinical outcome. Methods: We obtained archival FFPE tumor specimens from 56 patients with mRCC treated with sorafenib or bevacizumab. DNA from the FFPE blocks was analyzed with Affymetrix 250K Nsp SNP microarrays. We identified the presence of genomic imbalances and loss of heterozygosity (LOH) to obtain virtual karyotypes. We then evaluated candidate genes in gain/lost chromosomal regions by qPCR and immunohistochemistry (IHC) in the bevacizumab treated specimens. Results: In the bevacizumab cohort, HIF1-alpha containing14q loss showed a significant association with worse response to treatment (CR/ PR vs. SD/PD, Fisher exact test, p = 0.0473). In addition, HIF1A mRNA expression was significantly reduced in all samples with 14q loss and was associated with PFS (HR = 2.29, 95% CI = 1.01-5.16, p = 0.045). HIF-1alpha protein expression was also reduced in samples with 14q loss. Conclusions: Chromosomal imbalances are associated with outcomes in ccRCC patients treated with antiangiogenic agents, and can lead to changes in gene expression. Low HIF1A expression was strongly correlated with shorter PFS. We hypothesize that loss of 14q could lead to an imbalance in HIF-1alpha/HIF-2alpha activity, leading to increased HIF-2alpha and enhanced c-Myc expression, which improves tumor cell viability and engenders resistance to cellular stress induced by antiangiogenic therapy. No significant financial relationships to disclose.

Healthcare costs associated with bevacizumab and cetuximab in second-line treatment of metastatic colorectal cancer

Objective:To compare the health care costs of patients with metastatic colorectal cancer (mCRC) who received second-line treatment with Avastin (bevacizumab) versus Erbitux (cetuximab), from the third-party payer’s perspective.Methods:Patients with mCRC were selected from the PharMetrics claims database if they received second-line therapy containing either bevacizumab (second-line bevacizumab cohort) or cetuximab (second-line cetuximab cohort). Six-month costs following second-line therapy start date and average monthly healthcare costs while on second-line therapy (in 2009 US$) were calculated and compared between the two groups.Results:A total of 2188 patients with mCRC who met the eligibility criteria were included in the analysis, including 1808 patients receiving bevacizumab and 380 patients receiving cetuximab in second-line treatment. Demographic and baseline characteristics were similar between the two groups. Patients’ mean age was 61 years and 56% were males. In second-line treatment, bevacizumab was commonly used with oxaliplatin (43.5%) and irinotecan-based regimens (40.4%), whereas cetuximab was commonly used with irinotecan-based regimens (68.2%). Bevacizumab patients had significantly lower total all-cause healthcare costs than cetuximab patients (adjusted difference: –$10,231, p = 0.020), and lower medical costs (–$10,796, p = 0.012) during the 6 months following second-line therapy initiation. Approximately half of the difference in total all-cause healthcare costs was attributable to the lower chemotherapy and targeted therapy costs (–$5635, p = 0.032) of bevacizumab patients than those of cetuximab patients. While on second-line therapy, bevacizumab patients also had lower average monthly all-cause healthcare costs than cetuximab patients.Limitations:Second-line treatment in the current study was defined based on changes in mCRC medications, not based on disease progression due to the limited clinical information available in claims.Conclusion:The use of bevacizumab in second-line therapy was associated with significantly lower healthcare costs in mCRC patients, compared to the use of cetuximab.