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Overall Survival Comparison Between MET Subgroups by Treatment Disposition

PDF file - 109K, PCR Primer Sequences; Baseline Demographic and Clinical Characteristics for Patients With and Without Available Multigene Information; Mutations Identified In Available Patient Tumor Specimens

PDF file - 22K, Supplemental Fig. S3. Effect of cytoplasmic MET immunohistochemistry (IHC) staining on objective response rate in patients treated with panitumumab (pmab) plus rilotumumab (AMG 102) versus pmab plus placebo.

PDF file - 37K, Supplemental Fig. S4. The effect of baseline IGF and IGF-related protein expression on overall survival.

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Purpose: We evaluated the influence of RAS mutation status on the treatment effect of panitumumab in a prospective–retrospective analysis of a randomized, multicenter phase III study of panitumumab plus fluorouracil, leucovorin, and irinotecan (FOLFIRI) versus FOLFIRI alone as second-line therapy in patients with metastatic colorectal cancer (mCRC; ClinicalTrials.gov, NCT0039183).Experimental Design: Outcomes were from the study's primary analysis. RAS mutations beyond KRAS exon 2 (KRAS exons 3, 4; NRAS exons 2, 3, 4; BRAF exon 15) were detected by bidirectional Sanger sequencing in wild-type KRAS exon 2 tumor specimens. Progression-free survival (PFS) and overall survival (OS) were coprimary endpoints.Results: The RAS ascertainment rate was 85%; 18% of wild-type KRAS exon 2 tumors harbored other RAS mutations. For PFS and OS, the hazard ratio (HR) for panitumumab plus FOLFIRI versus FOLFIRI alone more strongly favored panitumumab in the wild-type RAS population than in the wild-type KRAS exon 2 population [PFS HR, 0.70 (95% confidence interval [CI], 0.54–0.91); P = 0.007 vs. 0.73 (95% CI, 0.59–0.90); P = 0.004; OS HR, 0.81 (95% CI, 0.63–1.03); P = 0.08 vs. 0.85 (95% CI, 0.70–1.04); P = 0.12]. Patients with RAS mutations were unlikely to benefit from panitumumab. Among RAS wild-type patients, the objective response rate was 41% in the panitumumab–FOLFIRI group versus 10% in the FOLFIRI group.Conclusions: Patients with RAS mutations were unlikely to benefit from panitumumab–FOLFIRI and the benefit–risk of panitumumab–FOLFIRI was improved in the wild-type RAS population compared with the wild-type KRAS exon 2 population. These findings support RAS testing for patients with mCRC. Clin Cancer Res; 21(24); 5469–79. ©2015 AACR.See related commentary by Salazar and Ciardiello, p. 5415

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Purpose: To investigate whether EGF receptor (EGFR) pathway mutations predicted response to monotherapy with panitumumab, an anti-EGFR monoclonal antibody, in a randomized phase III study of metastatic colorectal cancer.Experimental Design: Using massively parallel multigene sequencing, we analyzed 320 samples for 9 genes, with multigene sequence data from 288 (90%) samples.Results: Mutation rates were: KRAS (45%), NRAS (5%), BRAF (7%), PIK3CA (9%), PTEN (6%), TP53 (60%), EGFR (1%), AKT1 (CTNNB1 (2%). In the randomized study and open-label extension, 22 of 138 (16%) wild-type KRAS (codons 12/13/61) patients versus 0 of 103 mutant KRAS (codons 12/13) patients had objective responses. Of 6 mutant KRAS (codon 61) patients, 1 with a Q61H mutation achieved partial response during the extension. Among wild-type KRAS (codons 12/13/61) patients, 0 of 9 patients with NRAS mutations, 0 of 13 with BRAF mutations, 2 of 10 with PIK3CA mutations, 1 of 9 with PTEN mutations, and 1 of 2 with CTNNB1 mutations responded to panitumumab. No patients responded to best supportive care alone. Panitumumab treatment was associated with longer progression-free survival (PFS) among wild-type KRAS (codons 12/13/61) patients [HR, 0.39; 95% confidence interval (CI), 0.28–0.56]. Among wild-type KRAS patients, a treatment effect for PFS favoring panitumumab occurred in patients with wild-type NRAS (HR, 0.39; 95% CI, 0.27–0.56) and wild-type BRAF (HR, 0.37; 95% CI, 0.24–0.55) but not mutant NRAS (HR, 1.94; 95% CI, 0.44–8.44).Conclusions: These results show the feasibility and potential clinical use of next-generation sequencing for evaluating predictive biomarkers. Clin Cancer Res; 19(7); 1902–12. ©2012 AACR.

PDF file - 76K, Supplemental Fig. S1. (A) Randomized phase Ib/II trial of panitumumab plus rilotumumab (AMG 102) or ganitumab (AMG 479). (B) CONSORT diagram for part 2. *Panitumumab 6 mg/kg; rilotumumab 10 mg/kg with dose de-escalation to 5 mg/kg as necessary. �Panitumumab 6 mg/kg; rilotumumab 10 mg/kg; ganitumab 12 mg/kg. �Rilotumumab 10 mg/kg; ganitumab 12 mg/kg.

PDF file - 883K, Patient disposition by treatment group. IP, investigational product; MP, mitoxantrone and prednisone. *Patient had a decrease in hemoglobin prior to administration of IP on day 1 of cycle 1. �Patient had delays to cycles prior to cycle 12.

PDF file - 38K, Supplemental Fig. S5. The effect of baseline IGF and IGF-related protein expression on objective response rate.

PDF file - 38K, Supplemental Fig. S2. Best percent change of the sum of longest diameters of target lesions from baseline to post-baseline. (A) Panitumumab plus rilotumumab.(B) Panitumumab plus ganitumab. (C) Panitumumab alone.

Purpose: Rilotumumab is an investigational, fully human monoclonal antibody to hepatocyte growth factor. In a randomized phase II study, trends toward improved survival were observed with rilotumumab (7.5 or 15 mg/kg) plus epirubicin, cisplatin, and capecitabine (ECX) versus placebo plus ECX in gastric/gastroesophageal junction (GEJ) cancer patients, especially in MET-positive patients. Here, we quantitatively characterized the longitudinal exposure–response [tumor growth (TG) and overall survival (OS)] relationship for rilotumumab.Experimental Design: Rilotumumab concentrations, tumor sizes, and survival time from the phase II study were pooled to develop a longitudinal exposure versus TG model and parametric OS model that explored predictive/prognostic/treatment effects (MET expression, rilotumumab exposure, relative tumor size). Model evaluation included visual predictive checks, nonparametric bootstrap, and normalized prediction distribution errors. Simulations were undertaken to predict the relationship between rilotumumab dose and OS.Results: Rilotumumab exhibited linear time-independent pharmacokinetics not affected by MET expression. The TG model adequately described tumor size across arms. A Weibull distribution best described OS. Rilotumumab exposure and change in tumor size from baseline at week 24 were predictive of OS. MET-positive patients showed shorter survival and responded better to rilotumumab than MET-negative patients. Simulations predicted a median (95% confidence interval) HR of 0.38 (0.18–0.60) in MET-positive patients treated with 15 mg/kg rilotumumab Q3W.Conclusions: Rilotumumab plus ECX demonstrated concentration-dependent effects on OS, influenced by MET expression, and tumor size in gastric/GEJ cancer patients. These findings support the phase II testing of rilotumumab 15 mg/kg every 3 weeks in MET-positive gastric/GEJ cancer (RILOMET-1; NCT01697072). Clin Cancer Res; 21(11); 2453–61. ©2015 AACR.

PDF file - 1418K, Forest plot of the treatment effect of rilotumumab compared with placebo on OS by covariate subgroups in the intention-to-treat analysis set. ECOG, Eastern Cooperative Oncology Group; PD, progressive disease.

Purpose: Panitumumab, a fully human anti-epidermal growth factor receptor monoclonal antibody (mAb), has demonstrated efficacy in patients with wild-type KRAS metastatic colorectal cancer (mCRC). Rilotumumab and ganitumab are investigational, fully human mAbs against hepatocyte growth factor (HGF)/scatter factor and IGF1R, respectively. Here we evaluate combining rilotumumab or ganitumab with panitumumab in previously treated patients with wild-type KRAS mCRC.Experimental Design: Part 1 was a phase Ib dose-finding study of panitumumab plus rilotumumab. The primary endpoint was the incidence of dose-limiting toxicities (DLT). Part 2 was a randomized phase II trial of panitumumab in combination with rilotumumab, ganitumab, or placebo. The primary endpoint was objective response rate (ORR); safety, progression-free survival (PFS), and overall survival (OS) were secondary endpoints. Archival tissue specimens were collected for exploratory correlative work.Results: In part 1, no DLTs were reported. A recommended phase II dose of 10 mg/kg rilotumumab was selected. In part 2, for the panitumumab plus rilotumumab (n = 48), panitumumab plus ganitumab (n = 46), and panitumumab plus placebo arms (n = 48), the ORRs were 31%, 22%, and 21%, respectively. The median PFS was 5.2, 5.3, and 3.7 months and median OS 13.8, 10.6, and 11.6 months, respectively. Adverse events were tolerable. Exploratory biomarker analyses, including MET and IGF-related protein expression, failed to indicate conclusive predictive evidence on efficacy endpoints.Conclusions: Panitumumab plus rilotumumab met the prespecified criterion for improvement in ORR whereas ganitumab did not. This is the first study to suggest a benefit for combining an HGF inhibitor (rilotumumab) with panitumumab in previously treated patients with wild-type KRAS mCRC. Clin Cancer Res; 20(16); 4240–50. ©2014 AACR.

PDF file - 28K, Kaplan-Meier plot of OS (A) and PFS (B) by tumor MET expression in all treatment arms combined.

Purpose: Hepatocyte growth factor (HGF) is a hypoxia-induced secreted protein that binds to cMet and regulates interleukin (IL)-8 expression. We evaluated the role of circulating HGF and IL-8 as prognostic and predictive factors for efficacy of tirapazamine (TPZ), a hypoxic cell cytotoxin.Experimental Design: Patients with stages III to IV head and neck cancer were randomized to receive radiotherapy with cisplatin (CIS) or CIS plus TPZ (TPZ/CIS). Eligibility for the substudy included plasma sample availability for HGF and IL-8 assay by ELISA and no major radiation deviations (N = 498). Analyses included adjustment for major prognostic factors. p16INK4A staining (human papillomavirus surrogate) was carried out on available tumors. Thirty-nine patients had hypoxia imaging with 18F-fluoroazomycin arabinoside (18FAZA)–positron emission tomography.Results: Elevated IL-8 level was associated with worse overall survival (OS) irrespective of treatment. There was an interaction between HGF and treatment arm (P = 0.053); elevated HGF was associated with worse OS in the control but not in the TPZ/CIS arm. Similar trends were observed in analyses restricted to p16INK4A-negative patients. Four subgroups defined by high and low HGF/IL-8 levels were examined for TPZ effect; the test for interaction with arm was P = 0.099. TPZ/CIS seemed to be beneficial for patients with high HGF and IL-8 but adverse for low HGF and high IL-8. Only HGF correlated with 18FAZA tumor standard uptake value.Conclusions: IL-8 is an independent prognostic factor irrespective of treatment. There is an interaction between HGF and treatment arm. Certain subgroups based on IL-8/HGF levels seemed to do better with TPZ/CIS while others did worse, highlighting the complexity of hypoxia targeting in unselected patients. Clin Cancer Res; 18(6); 1798–807. ©2012 AACR.

Supplementary Figure 1. Goodness-of-Fit Plots for the Pharmacokinetic Model

PDF file - 28K, Waterfall plot of the maximum change in the sum of the longest diameters of tumors from baseline in patients with evaluable tumor response per investigator assessment who received rilotumumab (A) or placebo (B). Fifteen patients in the rilotumumab group and five patients in the placebo group were omitted because post-baseline data were not available. PD, progressive disease; SD, stable disease; UE, unevaluable.

PDF file - 57K, Summary of tumor response and tumor genotype among patients who received treatment with panitumuab plus BSC or BSC alone in either the randomized phase 3 study or the extension and who had multigene sequencing information available. For all patients enrolled, tumor response was based on investigator assessment. BSC, best supportive care.

PDF file - 54K, Drug exposure

Contains: Table S1. RAS and BRAF Mutation Status Table S2. Objective Response Rate in Patients with Mutated RAS Table S3. Depth of Response and Early Tumor Response in Wild-type KRAS Exon 2 Patients Figure S1. Disposition of patients in the study and RAS ascertainment.

Purpose: The aims were to assess the safety, pharmacokinetics, maximum tolerated dose, and antitumor activity of AMG 102, a fully human hepatocyte growth factor/scatter factor (HGF/SF)–neutralizing monoclonal antibody, in patients with solid tumors.Experimental Design: Patients (N = 40) with refractory advanced solid tumors were enrolled into six sequential dose-escalation cohorts (0.5, 1, 3, 5, 10, or 20 mg/kg AMG 102 i.v. every 2 weeks) and a dose-expansion cohort (20 mg/kg AMG 102 every 2 weeks). Safety, anti–AMG 102 antibody formation, pharmacokinetics, tumor response, and exploratory biomarkers were assessed.Results: AMG 102 was well tolerated up to the planned maximum dose of 20 mg/kg, and the maximum tolerated dose was not reached. Treatment-related adverse events were generally mild and included fatigue (13%), constipation (8%), nausea (8%), vomiting (5%), anorexia (5%), myalgia (5%), and hypertension (5%). Two patients experienced dose-limiting toxicities: one patient (0.5 mg/kg cohort) experienced grade 3 hypoxia and grade 3 dyspnea and one patient (1 mg/kg cohort) experienced grade 3 upper gastrointestinal hemorrhage. No anti–AMG 102 antibodies were detected, and AMG 102 had linear pharmacokinetics within the dose range investigated. Sixteen of 23 (70%) evaluable patients had a best response of stable disease with progression-free survival ranging from 7.9 to 40 weeks. Circulating levels of the biomarker HGF/SF (bound and unbound) increased in a dose-dependent manner, whereas soluble c-Met concentrations were generally similar across doses.Conclusions: AMG 102 is safe and well tolerated, has a favorable pharmacokinetic profile, and will be further investigated as a monotherapy and in combination with other agents. Clin Cancer Res; 16(2); 699–710

Supplementary Data from Safety, Pharmacokinetics, and Pharmacodynamics of AMG 102, a Fully Human Hepatocyte Growth Factor–Neutralizing Monoclonal Antibody, in a First-in-Human Study of Patients with Advanced Solid Tumors

Supplementary Figure 2. Goodness-of-Fit Plots for the Tumor Growth Model

PDF file - 31K, Waterfall plot of the maximum change of PSA levels from baseline in patients who received rilotumumab (A) or placebo (B) in the intention-to-treat analysis set. A PSA response was defined as ≥50% decline in two consecutive PSA levels ≥3 weeks apart. Six patients in the rilotumumab group were omitted because post-baseline data were not available.

PDF file - 1076K, Kaplan-Meier plot of PFS by tumor MET subgroups in the combined rilotumumab and control arms (A) and forest plot of the biomarker effect of high versus low tumor MET expression on PFS within the combined rilotumumab and control arms (B). MP, mitoxantrone and prednisone; NA, not applicable.

Purpose: To evaluate the efficacy, safety, biomarkers, and pharmacokinetics of rilotumumab, a fully human, monoclonal antibody against hepatocyte growth factor (HGF)/scatter factor, combined with mitoxantrone and prednisone (MP) in patients with castration-resistant prostate cancer (CRPC).Experimental Design: This double-blinded phase II study randomized (1:1:1) patients with progressive, taxane-refractory CRPC to receive MP (12 mg/m2 i.v. day 1, 5 mg twice a day orally days 1–21, respectively) plus 15 mg/kg rilotumumab, 7.5 mg/kg rilotumumab, or placebo (i.v. day 1) every 3 weeks. The primary endpoint was overall survival (OS).Results: One hundred and forty-four patients were randomized. Median OS was 12.2 versus 11.1 months [HR, 1.10; 80% confidence interval (CI), 0.82–1.48] in the combined rilotumumab versus control arms. Median progression-free survival was 3.0 versus 2.9 months (HR, 1.02; 80% CI, 0.79–1.31). Treatment appeared well tolerated with peripheral edema (24% vs. 8%) being more common with rilotumumab. A trend toward unfavorable OS was observed in patients with high tumor MET expression regardless of treatment. Soluble MET levels increased in all treatment arms. Total HGF levels increased in the rilotumumab arms. Rilotumumab showed linear pharmacokinetics when co-administered with MP.Conclusions: Rilotumumab plus MP had manageable toxicities and showed no efficacy improvements in this estimation study. High tumor MET expression may identify patients with CRPC with poorer prognosis. Clin Cancer Res; 19(1); 215–24. ©2012 AACR.

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Background: To investigate tumour biomarker status and efficacy of first-line panitumumab+FOLFIRI for metastatic colorectal carcinoma (mCRC). Methods: 154 patients received first-line panitumumab + FOLFIRI every 14 days. Primary end point was objective response rate (ORR). Data were analysed by tumour RAS (KRAS/NRAS) and BRAF status, and baseline amphiregulin (AREG) expression. Results: Objective responses occurred more frequently in RAS wild type (WT) (59%) vs RAS mutant (MT) (41%) mCRC and in RAS WT/BRAF WT (68%) vs RAS or BRAF MT (37%) disease. Median response duration was longer in RAS WT (13.0 months) vs RAS MT (5.8 months) (hazard ratio (HR): 0.16). Median progression-free survival was longer in RAS WT vs MT (11.2 vs 7.3 months; HR, 0.37) and was also longer in RAS WT/BRAF WT vs RAS or BRAF MT (13.2 vs 6.9 months; HR, 0.25). Incidence of adverse events was similar regardless of RAS/BRAF status, and no new safety signals were noted. Among patients with RAS WT tumours, ORR was 67% with high AREG expression and 38% with low AREG expression. Conclusions: First-line panitumumab+FOLFIRI was associated with favourable efficacy in patients with RAS WT and RAS WT/BRAF WT vs MT mCRC tumours and was well tolerated.

MET and its sole ligand, hepatocyte growth factor (HGF), are promising targets in gastric and gastroesophageal junction cancer. We evaluated whether MET protein expression or MET gene amplification is prognostic for overall survival (OS) in Chinese patients with advanced gastric or gastroesophageal junction cancer. Archival formalin-fixed, paraffin-embedded tumor samples from patients with unresectable locally advanced or metastatic gastric or gastroesophageal junction cancer enrolled in clinical trials at Peking University Cancer Hospital from 2008 to 2010 were assessed for MET and phospho-MET (p-MET) expression by immunohistochemistry and MET amplification by FISH. MET-positive expression was defined as membrane protein staining in ≥25% of tumor cells. MET amplification was defined as MET:centromere 7 ratio >2.0. We tested the association of MET status with clinical characteristics and OS, and also evaluated the association between expression and amplification. One hundred sixty-eight patients were eligible. Of the evaluable samples, 53 of 137 (39%) were MET positive, eight of 134 (6%) were p-MET positive, and eight of 113 (7%) were MET amplified. Neither MET expression nor MET amplification were associated with clinical characteristics, except Lauren classification (P = 0.04); MET amplification was associated with diffuse type. No significant OS difference was observed between MET-positive and MET-negative populations, regardless of first-line chemotherapy received. In 95 evaluable patients, MET expression was significantly associated with MET amplification (P < 0.001); all MET-amplified tumor samples showed some MET expression. In 96 evaluable patients, p-MET positivity was significantly associated with MET amplification (P < 0.001). Further evaluation in larger and independent sample sets is warranted to confirm our findings. Mol Cancer Ther; 14(11); 2634–41. ©2015 AACR.

Objective To assess the safety and immunologic impact of inhibiting interferon-γ (IFNγ) with AMG 811, a human IgG1 monoclonal antibody against IFNγ, in patients with systemic lupus erythematosus (SLE). Methods Twenty-six patients with mild-to-moderate, stable SLE were administered placebo or a single dose of AMG 811, ranging from 2 mg to 180 mg subcutaneously or 60 mg intravenously. Results Similar to results previously reported following inhibition of type I IFNs, treatment of SLE patients with AMG 811 led to a dose-dependent modulation of the expression of genes associated with IFN signaling, as assessed by microarray analysis of the whole blood. The list of impacted genes overlapped with that identified by stimulating human whole blood with IFNγ and with those gene sets reported in the literature to be differentially expressed in SLE patients. Serum levels of IFNγ-induced chemokines, including IFNγ-inducible protein 10 (IP-10), were found to be elevated at baseline in SLE patients as compared to healthy volunteers. In contrast to previously reported results from studies using type I IFN–blocking agents, treatment with AMG 811 led to dose-related reductions in the serum levels of CXCL10 (IP-10). Conclusion The scope and nature of the biomarkers impacted by AMG 811 support targeting of IFNγ as a therapeutic strategy for SLE.

RAS family proteins (including KRAS and NRAS) play important roles in the epidermal growth factor receptor (EGFR) signaling pathway. Mutations in RAS genes (occurring at loci in exons 2, 3, and 4) often result in constitutive activation of RAS proteins and persistent downstream signaling. Mutations in KRAS exon 2 (codon 12/13) are an established predictor of lack of response to the anti-EGFR monoclonal antibodies cetuximab and panitumumab in patients with metastatic colorectal cancer (mCRC), and have been used routinely in clinical practice to identify patients unlikely to derive benefit from these therapies. However, a meaningful proportion of patients with mCRC have tumors bearing other mutations in RAS genes. Recent studies have demonstrated that evaluation of an extended panel of RAS mutations—including mutations in KRAS exon 2, 3, and 4 and NRAS exons 2, 3, and 4—can better define the patient population that is unlikely to benefit from anti-EGFR therapy, with concomitant improvements in outcomes in the more highly selected RAS wild-type group. This discovery has changed the practice of oncology and has the potential to spare patients from exposure to ineffective therapy. In the near future, it is important for the oncology community to validate extended RAS analysis assays and make certain that patients who are candidates for anti-EGFR therapy undergo appropriate testing and treatment.

Purpose: Rilotumumab is an investigational, fully human monoclonal antibody to hepatocyte growth factor. In a randomized phase II study, trends toward improved survival were observed with rilotumumab (7.5 or 15 mg/kg) plus epirubicin, cisplatin, and capecitabine (ECX) versus placebo plus ECX in gastric/gastroesophageal junction (GEJ) cancer patients, especially in MET-positive patients. Here, we quantitatively characterized the longitudinal exposure–response [tumor growth (TG) and overall survival (OS)] relationship for rilotumumab. Experimental Design: Rilotumumab concentrations, tumor sizes, and survival time from the phase II study were pooled to develop a longitudinal exposure versus TG model and parametric OS model that explored predictive/prognostic/treatment effects (MET expression, rilotumumab exposure, relative tumor size). Model evaluation included visual predictive checks, nonparametric bootstrap, and normalized prediction distribution errors. Simulations were undertaken to predict the relationship between rilotumumab dose and OS. Results: Rilotumumab exhibited linear time-independent pharmacokinetics not affected by MET expression. The TG model adequately described tumor size across arms. A Weibull distribution best described OS. Rilotumumab exposure and change in tumor size from baseline at week 24 were predictive of OS. MET-positive patients showed shorter survival and responded better to rilotumumab than MET-negative patients. Simulations predicted a median (95% confidence interval) HR of 0.38 (0.18–0.60) in MET-positive patients treated with 15 mg/kg rilotumumab Q3W. Conclusions: Rilotumumab plus ECX demonstrated concentration-dependent effects on OS, influenced by MET expression, and tumor size in gastric/GEJ cancer patients. These findings support the phase II testing of rilotumumab 15 mg/kg every 3 weeks in MET-positive gastric/GEJ cancer (RILOMET-1; NCT01697072). Clin Cancer Res; 21(11); 2453–61. ©2015 AACR.

Summary Background Panitumumab is a fully human monoclonal antibody that targets EGFR. We aimed to compare chemoradiotherapy plus panitumumab with chemoradiotherapy alone in patients with unresected, locally advanced squamous-cell carcinoma of the head and neck. Methods In this international, open-label, randomised, controlled, phase 2 trial, we recruited patients with locally advanced squamous-cell carcinoma of the head and neck from 41 sites in nine countries worldwide. Patients aged 18 years and older with stage III, IVa, or IVb, previously untreated, measurable (≥10 mm for at least one dimension), locally advanced squamous-cell carcinoma of the head and neck (non-nasopharygeal) and an Eastern Cooperative Oncology Group performance status of 0–1 were randomly assigned (2:3) by an independent vendor to open-label chemoradiotherapy (three cycles of cisplatin 100 mg/m 2 ) or panitumumab plus chemoradiotherapy (three cycles of intravenous panitumumab 9·0 mg/kg every 3 weeks plus cisplatin 75 mg/m 2 ) using stratified randomisation with a block size of five. All patients received 70 Gy to gross tumour and 50 Gy to areas at risk for subclinical disease with standard fractionation. The primary endpoint was local-regional control at 2 years, analysed in all randomised patients who received at least one dose of their assigned protocol-specific treatment (chemotherapy, radiation, or panitumumab). The trial is closed and this is the final analysis. This trial is registered with ClinicalTrials.gov, number NCT00500760. Findings Between Oct 26, 2007, and March 26, 2009, 153 patients were enrolled and 150 received treatment (63 in the chemoradiotherapy group and 87 in the panitumumab plus chemoradiotherapy group). Local-regional control at 2 years was 68% (95% CI 54–78) in the chemoradiotherapy group and 61% (50–71) in the panitumumab plus chemoradiotherapy group. The most frequent grade 3–4 adverse events were dysphagia (17 [27%] of 63 patients in the chemoradiotherapy group vs 35 [40%] of 87 in the panitumumab plus chemoradiotherapy group), mucosal inflammation (15 [24%] vs 48 [55%]), and radiation skin injury (eight [13%] vs 27 [31%]). Serious adverse events were reported in 20 (32%) of 63 patients in the chemoradiotherapy group and in 37 (43%) of 87 patients in the panitumumab plus chemoradiotherapy group. Interpretation In patients with locally advanced squamous-cell carcinoma of the head and neck, the addition of panitumumab to standard fractionation radiotherapy and cisplatin did not confer any benefit, and the role of EGFR inhibition in these patients needs to be reassessed. Funding Amgen.

Summary Background We aimed to compare panitumumab, a fully human monoclonal antibody against EGFR, plus radiotherapy with chemoradiotherapy in patients with unresected, locally advanced squamous-cell carcinoma of the head and neck. Methods In this international, open-label, randomised, controlled, phase 2 trial, we recruited patients with locally advanced squamous-cell carcinoma of the head and neck from 22 sites in eight countries worldwide. Patients aged 18 years and older with stage III, IVa, or IVb, previously untreated, measurable (≥10 mm for at least one dimension), locally advanced squamous-cell carcinoma of the head and neck (non-nasopharygeal) and an Eastern Cooperative Oncology Group performance status of 0–1 were randomly assigned (2:3) by an independent vendor to open-label chemoradiotherapy (two cycles of cisplatin 100 mg/m 2 during radiotherapy) or to radiotherapy plus panitumumab (three cycles of panitumumab 9 mg/kg every 3 weeks administered with radiotherapy) using a stratified randomisation with a block size of five. All patients received 70–72 Gy to gross tumour and 54 Gy to areas of subclinical disease with accelerated fractionation radiotherapy. The primary endpoint was local-regional control at 2 years, analysed in all randomly assigned patients who received at least one dose of their assigned protocol-specific treatment (chemotherapy, radiation, or panitumumab). The trial is closed and this is the final analysis. This study is registered with ClinicalTrials.gov, number NCT00547157. Findings Between Nov 30, 2007, and Nov 16, 2009, 152 patients were enrolled, and 151 received treatment (61 in the chemoradiotherapy group and 90 in the radiotherapy plus panitumumab group). Local-regional control at 2 years was 61% (95% CI 47–72) in the chemoradiotherapy group and 51% (40–62) in the radiotherapy plus panitumumab group. The most frequent grade 3–4 adverse events were mucosal inflammation (25 [40%] of 62 patients in the chemoradiotherapy group vs 37 [42%] of 89 patients in the radiotherapy plus panitumumab group), dysphagia (20 [32%] vs 36 [40%]), and radiation skin injury (seven [11%] vs 21 [24%]). Serious adverse events were reported in 25 (40%) of 62 patients in the chemoradiotherapy group and in 30 (34%) of 89 patients in the radiotherapy plus panitumumab group. Interpretation Panitumumab cannot replace cisplatin in the combined treatment with radiotherapy for unresected stage III–IVb squamous-cell carcinoma of the head and neck, and the role of EGFR inhibition in locally advanced squamous-cell carcinoma of the head and neck needs to be reassessed. Funding Amgen.

Background: Rilotumumab, an investigational, monoclonal antibody, inhibits MET-mediated signalling. In a randomized phase 2 trial of rilotumumab±epirubicin/cisplatin/capecitabine in gastric or oesophagogastric junction cancer, patients receiving rilotumumab showed a trend towards improved survival, especially in MET-positive patients, but no clear dose–response relationship was observed. Exposure-response and biomarker analyses were used for dose selection and to differentiate patient subpopulations that may benefit most from treatment. Here, we analyse rilotumumab exposure–survival and exposure–safety and the impact of MET expression on these relationships. Methods: Individual rilotumumab exposure parameters were generated using population pharmacokinetic modelling. Relationships among rilotumumab dose (7.5 and 15 mg kg−1), exposure, and clinical outcomes (progression-free survival (PFS) and overall survival (OS)) were evaluated with Cox regression models and Kaplan–Meier plots. MET status and other baseline covariates were evaluated in subgroup and multivariate analyses. Treatment-emergent adverse events were summarised by exposure. Results: Among MET-positive patients, higher rilotumumab exposure, vs placebo and low exposure, was associated with improved median PFS (80% CI: 7.0 (5.7–9.7) vs 4.4 (2.9–4.9) and 5.5 (4.2–6.8) months) and OS (13.4 (10.6–18.6) vs 5.7 (4.7–10.2) and 8.1 (6.9–11.1) months) without increased toxicity. No rilotumumab benefit was seen among MET-negative patients. Conclusions: Rilotumumab had an exposure-dependent treatment effect in patients with MET-positive gastric or oesophagogastric junction cancer.

Summary Background Dysregulation of the hepatocyte growth factor (HGF)/MET pathway promotes tumour growth and metastasis. Rilotumumab is a fully human, monoclonal antibody that neutralises HGF. We aimed to assess the safety, efficacy, biomarkers, and pharmacokinetics of rilotumumab combined with epirubicin, cisplatin, and capecitabine (ECX) in patients with advanced gastric or oesophagogastric junction cancer. Methods We recruited patients (≥18 years old) with unresectable locally advanced or metastatic gastric or oesophagogastric junction adenocarcinoma, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, who had not received previous systemic therapy, from 43 sites worldwide. Phase 1b was an open-label, dose de-escalation study to identify a safe dose of rilotumumab (initial dose 15 mg/kg intravenously on day 1) plus ECX (epirubicin 50 mg/m 2 intravenously on day 1, cisplatin 60 mg/m 2 intravenously on day 1, capecitabine 625 mg/m 2 twice a day orally on days 1–21, respectively), administered every 3 weeks. The phase 1b primary endpoint was the incidence of dose-limiting toxicities in all phase 1b patients who received at least one dose of rilotumumab and completed the dose-limiting toxicity assessment window (first cycle of therapy). Phase 2 was a double-blind study that randomly assigned patients (1:1:1) using an interactive voice response system to receive rilotumumab 15 mg/kg, rilotumumab 7·5 mg/kg, or placebo, plus ECX (doses as above), stratified by ECOG performance status and disease extent. The phase 2 primary endpoint was progression-free survival (PFS), analysed by intention to treat. The study is registered with ClinicalTrials.gov, number NCT00719550. Findings Seven of the nine patients enrolled in the phase 1b study received at least one dose of rilotumumab 15 mg/kg, only two of whom had three dose-limiting toxicities: palmar-plantar erythrodysesthesia, cerebral ischaemia, and deep-vein thrombosis. In phase 2, 121 patients were randomly assigned (40 to rilotumumab 15 mg/kg; 42 to rilotumumab 7·5 mg/kg; 39 to placebo). Median PFS was 5·1 months (95% CI 2·9–7·0) in the rilotumumab 15 mg/kg group, 6·8 months (4·5–7·5) in the rilotumumab 7·5 mg/kg group, 5·7 months (4·5–7·0) in both rilotumumab groups combined, and 4·2 months (2·9–4·9) in the placebo group. The hazard ratio for PFS events compared with placebo was 0·69 (80% CI 0·49–0·97; p=0·164) for rilotumumab 15 mg/kg, 0·53 (80% CI 0·38–0·73; p=0·009) for rilotumumab 7·5 mg/kg, and 0·60 (80% CI 0·45–0·79; p=0·016) for combined rilotumumab. Any grade adverse events more common in the combined rilotumumab group than in the placebo group included haematological adverse events (neutropenia in 44 [54%] of 81 patients vs 13 [33%] of 39 patients; anaemia in 32 [40%] vs 11 [28%]; and thrombocytopenia in nine [11%] vs none), peripheral oedema (22 [27%] vs three [8%]), and venous thromboembolism (16 [20%] vs five [13%]). Grade 3–4 adverse events more common with rilotumumab included neutropenia (36 [44%] vs 11 [28%]) and venous thromboembolism (16 [20%] vs four [10%]). Serious adverse events were balanced between groups except for anaemia, which occurred more frequently in the combined rilotumumab group (ten [12%] vs none). Interpretation Rilotumumab plus ECX had no unexpected safety signals and showed greater activity than placebo plus ECX. A phase 3 study of the combination in MET-positive gastric and oesophagogastric junction cancer is in progress. Funding Amgen Inc.

Background: The Panitumumab Randomized trial In combination with chemotherapy for Metastatic colorectal cancer to determine Efficacy (PRIME) demonstrated that panitumumab-FOLFOX4 significantly improved progression-free survival (PFS) versus FOLFOX4 as first-line treatment of wild-type (WT) KRAS metastatic colorectal cancer (mCRC), the primary end point of the study. Patients and methods: Patients were randomized 1:1 to panitumumab 6.0 mg/kg every 2 weeks + FOLFOX4 (arm 1) or FOLFOX4 (arm 2). This prespecified final descriptive analysis of efficacy and safety was planned for 30 months after the last patient was enrolled. Results: A total of 1183 patients were randomized. Median PFS for WT KRAS mCRC was 10.0 months [95% confidence interval (CI) 9.3-11.4 months] for arm 1 and 8.6months (95% CI 7.5-9.5 months) for arm 2; hazard ratio (HR) = 0.80; 95% CI 0.67-0.95; P = 0.01. Median overall survival (OS) forWT KRAS mCRC was 23.9 months (95%CI 20.3-27.7 months) for arm 1 and 19.7 months (95% CI 17.6-22.7 months) for arm 2; HR = 0.88; 95% CI 0.73-1.06; P=0.17 (68%OS events). An exploratory analysis of updated survival (>80%OS events) was carried out which demonstrated improvement in OS; HR = 0.83; 95%CI 0.70-0.98; P=0.03 forWT KRASmCRC. The adverse event profile was consistent with the primary analysis. Conclusions: In WT KRAS mCRC, PFS was improved, objective response was higher, and there was a trend toward improved OS with panitumumab-FOLFOX4, with significant improvement in OS observed in an updated analysis of survival in patients with WT KRAS mCRC treated with panitumumab + FOLFOX4 versus FOLFOX4 alone (P = 0.03). These data support a positive benefit-risk profile for panitumumab-FOLFOX4 for patients with previously untreated WT KRAS mCRC. KRAS testing is critical to select appropriate patients for treatment with panitumumab. © The Author 2014. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved.

e13016 Background: Whole-genome sequencing (WGS) of formalin-fixed, paraffin-embedded (FFPE) samples could enable novel insights from archival sample collections, yet robust FFPE WGS is challenged by fragmented DNA, uneven genomic coverage & sequencing artifacts attributed to FFPE fixation. We report our proprietary extraction & library preparation methodology (SeqPlus) with high quality, uniform WGS sequencing performance comparable to that from fresh-frozen samples. Methods: We analyzed 20 paired esophageal carcinoma (EC) samples i.e., primary tumors & matched germline samples to assess SeqPlus performance on 10-15-year-old FFPE tissues, measure variant concordance between WGS and a high-depth sequencing panel (269 genes, 400x coverage) & identify novel genomic features. Results: At a targeted 70x WGS tumor sequencing depth, 93% of the genome was covered by ³ 20 reads, 99% of bases had 10x coverage & average duplicate reads were 31%. We noted similar transition/transversion ratios & mutational spectra as from fresh-frozen EC specimens, suggesting that extraction & library preparation contributes to prior FFPE artifacts. Concordance of tumor-specific SNVs & indels derived from WGS & targeted panel was high at 86%. All 76 targeted panel-detected variants above the WGS limit of detection (mutant allele frequency [MAF] > 10%) were detected by WGS, 2 variants (2 tumors) were detected only by WGS, and 12 variants at MAF ≤ 6% (9 tumors) were only detected by the targeted panel. Tumor WGS yielded SNV, indels & CNV findings beyond variants detected by targeted sequencing. WGS enabled detection of 10.4 putative cancer variants per tumor compared to 12 variants per patient from frozen specimens and a median of 7 (up to 16) cancer-associated variants in genes outside the targeted panel. WGS copy number analysis revealed CCND1, EGFR, TP63, and SOX2amplification, CDKN2A/B deletion and additional unrecognized genomic aberrations. Conclusions: Our study reinforces the utility of high-quality, uniform WGS sequencing of archival FFPE cancer samples with SeqPlus and unlocks the potential for massive-scale retrospective genomic analysis of archived pathology samples with associated clinical & outcomes data.

Patients with metastatic colorectal cancer that harbors KRAS mutations in exon 2 do not benefit from anti-epidermal growth factor receptor (EGFR) therapy. Other activating RAS mutations may also be negative predictive biomarkers for anti-EGFR therapy.In this prospective-retrospective analysis, we assessed the efficacy and safety of panitumumab plus oxaliplatin, fluorouracil, and leucovorin (FOLFOX4) as compared with FOLFOX4 alone, according to RAS (KRAS or NRAS) or BRAF mutation status. A total of 639 patients who had metastatic colorectal cancer without KRAS mutations in exon 2 had results for at least one of the following: KRAS exon 3 or 4; NRAS exon 2, 3, or 4; or BRAF exon 15. The overall rate of ascertainment of RAS status was 90%.Among 512 patients without RAS mutations, progression-free survival was 10.1 months with panitumumab-FOLFOX4 versus 7.9 months with FOLFOX4 alone (hazard ratio for progression or death with combination therapy, 0.72; 95% confidence interval [CI], 0.58 to 0.90; P=0.004). Overall survival was 26.0 months in the panitumumab-FOLFOX4 group versus 20.2 months in the FOLFOX4-alone group (hazard ratio for death, 0.78; 95% CI, 0.62 to 0.99; P=0.04). A total of 108 patients (17%) with nonmutated KRAS exon 2 had other RAS mutations. These mutations were associated with inferior progression-free survival and overall survival with panitumumab-FOLFOX4 treatment, which was consistent with the findings in patients with KRAS mutations in exon 2. BRAF mutations were a negative prognostic factor. No new safety signals were identified.Additional RAS mutations predicted a lack of response in patients who received panitumumab-FOLFOX4. In patients who had metastatic colorectal cancer without RAS mutations, improvements in overall survival were observed with panitumumab-FOLFOX4 therapy. (Funded by Amgen and others; PRIME ClinicalTrials.gov number, NCT00364013.).

This phase 2 estimation study evaluated docetaxel/cisplatin with/without panitumumab, an anti-epidermal growth factor receptor monoclonal antibody, as first-line therapy for recurrent/metastatic squamous cell carcinoma of the head and neck (SCCHN).Randomized patients received docetaxel/cisplatin (75mg/m(2) each) with/without panitumumab (9mg/kg) in 21-day cycles. Patients randomized to panitumumab+chemotherapy could continue panitumumab monotherapy after completing six chemotherapy cycles without progression; patients randomized to chemotherapy alone could receive second-line panitumumab after progression. Progression-free survival (PFS) was the primary endpoint. Secondary endpoints included overall survival (OS), overall response rate (ORR), time to response (TTR), duration of response (DOR), and safety. A protocol amendment limited enrollment to patients70years owing to excess toxicity in older patients and added mandatory pegfilgrastim/filgrastim support. Outcomes were also analyzed by human papillomavirus status.103 of the 113 enrolled patients were evaluable and randomized to receive ⩾1 dose of first-line treatment. Median PFS for panitumumab+chemotherapy was 6.9 (95% CI=4.7-8.3) months versus 5.5 (95% CI=4.1-6.8) months for chemotherapy alone (hazard ratio [HR]=0.629; 95% CI=0.395-1.002; P=0.048). ORR for panitumumab+chemotherapy was 44% (95% CI=31-58%) versus 37% (95% CI=24-51%) for chemotherapy alone (odds ratio [OR]=1.37; 95% CI=0.57-3.33). Median OS for panitumumab+chemotherapy was 12.9 (95% CI=9.4-18.5) months versus 13.8 (95% CI=11.8-22.9) months for chemotherapy alone (HR=1.103; 95% CI=0.709-1.717). Median TTR for panitumumab+chemotherapy treatment was 6.9weeks versus 11.0weeks for chemotherapy alone. Median DOR was 8.0 (95% CI=5.7-11.1) months with panitumumab+chemotherapy versus 5.1 (95% CI=4.4-7.2) months with chemotherapy alone. Grade 3/4 adverse event incidence was 73% with panitumumab+chemotherapy versus 56% with chemotherapy alone. 41% and 55% of patients in the panitumumab+chemotherapy and chemotherapy-alone arms, respectively, received panitumumab monotherapy.The addition of panitumumab to docetaxel/cisplatin may improve PFS in recurrent/metastatic SCCHN and has the potential to improve outcomes in these fully, or mostly, active patients.

Colorectal tumors that are wild-type (WT) for KRAS are often sensitive to EGFR blockade, but almost always develop resistance within several months of initiating therapy1,2. The mechanisms underlying this acquired resistance to anti-EGFR antibodies are largely unknown. This situation stands in marked contrast to that of small molecule targeted agents, such as inhibitors of ABL, EGFR, BRAF, and MEK, in which mutations in the genes encoding the protein targets render the tumors resistant to the effects of the drugs3–6. The simplest hypothesis to account for the development of resistance to EGFR blockade are that rare cells with KRAS mutations pre-exist at low levels in tumors with ostensibly WT KRAS genes. Though this hypothesis would seem readily testable, there is no evidence in pre-clinical models to support it, nor is there data from patients. To test this hypothesis, we determined whether mutant KRAS DNA could be detected in the circulation of 28 patients receiving monotherapy with panitumumab, a therapeutic anti-EGFR antibody. We found that nine of 24 (38%) patients whose tumors were initially KRAS WT developed detectable mutations in KRAS in their sera, three of which developed multiple different KRAS mutations. The appearance of these mutations was very consistent, generally occurring between five to six months following treatment. Mathematical modeling indicated that the mutations were present in expanded subclones prior to the initiation of panitumumab. These results suggest that the emergence of KRAS mutations is a mediator of acquired resistance to EGFR blockade and that these mutations can be detected in a non-invasive manner. Moreover, they explain why solid tumors develop resistance to targeted therapies in a highly reproducible fashion.

Purpose Panitumumab, a fully human anti–epidermal growth factor receptor (EGFR) monoclonal antibody that improves progression-free survival (PFS), is approved as monotherapy for patients with chemotherapy-refractory metastatic colorectal cancer (mCRC). The Panitumumab Randomized Trial in Combination With Chemotherapy for Metastatic Colorectal Cancer to Determine Efficacy (PRIME) was designed to evaluate the efficacy and safety of panitumumab plus infusional fluorouracil, leucovorin, and oxaliplatin (FOLFOX4) versus FOLFOX4 alone as initial treatment for mCRC. Patients and Methods In this multicenter, phase III trial, patients with no prior chemotherapy for mCRC, Eastern Cooperative Oncology Group performance status of 0 to 2, and available tissue for biomarker testing were randomly assigned 1:1 to receive panitumumab-FOLFOX4 versus FOLFOX4. The primary end point was PFS; overall survival (OS) was a secondary end point. Results were prospectively analyzed on an intent-to-treat basis by tumor KRAS status. Results KRAS results were available for 93% of the 1,183 patients randomly assigned. In the wild-type (WT) KRAS stratum, panitumumab-FOLFOX4 significantly improved PFS compared with FOLFOX4 (median PFS, 9.6 v 8.0 months, respectively; hazard ratio [HR], 0.80; 95% CI, 0.66 to 0.97; P = .02). A nonsignificant increase in OS was also observed for panitumumab-FOLFOX4 versus FOLFOX4 (median OS, 23.9 v 19.7 months, respectively; HR, 0.83; 95% CI, 0.67 to 1.02; P = .072). In the mutant KRAS stratum, PFS was significantly reduced in the panitumumab-FOLFOX4 arm versus the FOLFOX4 arm (HR, 1.29; 95% CI, 1.04 to 1.62; P = .02), and median OS was 15.5 months versus 19.3 months, respectively (HR, 1.24; 95% CI, 0.98 to 1.57; P = .068). Adverse event rates were generally comparable across arms with the exception of toxicities known to be associated with anti-EGFR therapy. Conclusion This study demonstrated that panitumumab-FOLFOX4 was well tolerated and significantly improved PFS in patients with WT KRAS tumors and underscores the importance of KRAS testing for patients with mCRC.

Purpose: We evaluated the influence of RAS mutation status on the treatment effect of panitumumab in a prospective–retrospective analysis of a randomized, multicenter phase III study of panitumumab plus fluorouracil, leucovorin, and irinotecan (FOLFIRI) versus FOLFIRI alone as second-line therapy in patients with metastatic colorectal cancer (mCRC; ClinicalTrials.gov, NCT0039183). Experimental Design: Outcomes were from the study's primary analysis. RAS mutations beyond KRAS exon 2 (KRAS exons 3, 4; NRAS exons 2, 3, 4; BRAF exon 15) were detected by bidirectional Sanger sequencing in wild-type KRAS exon 2 tumor specimens. Progression-free survival (PFS) and overall survival (OS) were coprimary endpoints. Results: The RAS ascertainment rate was 85%; 18% of wild-type KRAS exon 2 tumors harbored other RAS mutations. For PFS and OS, the hazard ratio (HR) for panitumumab plus FOLFIRI versus FOLFIRI alone more strongly favored panitumumab in the wild-type RAS population than in the wild-type KRAS exon 2 population [PFS HR, 0.70 (95% confidence interval [CI], 0.54–0.91); P = 0.007 vs. 0.73 (95% CI, 0.59–0.90); P = 0.004; OS HR, 0.81 (95% CI, 0.63–1.03); P = 0.08 vs. 0.85 (95% CI, 0.70–1.04); P = 0.12]. Patients with RAS mutations were unlikely to benefit from panitumumab. Among RAS wild-type patients, the objective response rate was 41% in the panitumumab–FOLFIRI group versus 10% in the FOLFIRI group. Conclusions: Patients with RAS mutations were unlikely to benefit from panitumumab–FOLFIRI and the benefit–risk of panitumumab–FOLFIRI was improved in the wild-type RAS population compared with the wild-type KRAS exon 2 population. These findings support RAS testing for patients with mCRC. Clin Cancer Res; 21(24); 5469–79. ©2015 AACR. See related commentary by Salazar and Ciardiello, p. 5415

4034 Background: Estimates of the frequency of genomic/proteomic alterations in MET in solid tumors vary widely, but a growing body of evidence suggests that MET amplification and/or Met expression...

Contains fulltext : 153716.pdf (Publisher’s version ) (Closed access) BACKGROUND: The use of epidermal growth factor receptor inhibitors to treat metastatic colorectal cancer (mCRC) patients requires prior confirmation of tumour wild type (WT) RAS mutation status (exons 2/3/4 for KRAS or NRAS). This retrospective pooled analysis aims to robustly estimate RAS mutation prevalence and individual variation patterns in mCRC patients. METHOD: Individual patient data from five randomised, controlled panitumumab studies (three phase III, one phase II and one phase Ib/II) were pooled for this analysis. The phase III studies included mCRC patients independent of RAS mutation status; the phase II and Ib/II studies included mCRC patients with confirmed WT KRAS exon 2 status. Four studies conducted RAS testing using Sanger sequencing; one study used a combination of next-generation sequencing and Sanger sequencing. In order to assign overall RAS status, the mutation status of all exons 2/3/4 KRAS or NRAS was required to be known. RESULTS: Data from 3196 mCRC patients from 36 countries were included in the analysis. The overall unadjusted RAS mutation prevalence in mCRC patients was 55.9% (95% confidence interval (CI): [53.9-57.9%]), with the following distribution observed: KRAS exon 2 (prevalence 42.6% [40.7-44.5%]); KRAS exon 3 (3.8% [2.9-4.9%]); KRAS exon 4 (6.2% [5.0-7.6%]); NRAS exon 2 (2.9% [2.1-3.9%]); NRAS exon 3 (4.2% [3.2-5.4%]); NRAS exon 4 (0.3% [0.1-0.7%]). Differences in RAS mutation prevalence estimates were observed by study (p=0.001), gender (p=0.030), and by country (p=0.028). CONCLUSIONS: This analysis provides robust estimates of overall RAS mutation prevalence and individual variation patterns in mCRC patients.

Background Improvements in both performance and cost for next-generation sequencing (NGS) have spurred its rapid adoption for clinical applications. We designed and optimized a pan-cancer target-enrichment panel for 51 well-established oncogenes and tumor suppressors, in conjunction with a bioinformatic pipeline informed by in-process controls and pre- and post-analytical quality control measures. Methods The evaluation of this workflow consisted of sequencing mixtures of intact DNA to establish analytical sensitivity and precision, utilization of heuristics to identify systematic artifacts, titration studies of intact and FFPE samples for input optimization, and incorporation of orthogonal sequencing strategies to increase both positive predictive value and variant detection. We also used 128 FFPE samples to assess clinical accuracy and incorporated the previously described quantitative functional index (QFI) for sample qualification as part of detailing complete system performance. Results We observed a concordance correlation coefficient of 0.99 between the observed versus expected percent variant at 250 ng input across 4 independent sequencing runs. A subset of the systematic variants were confirmed to be barely detectable on an independent sequencing platform (Wilcox signed-rank test p-value

Purpose: Panitumumab, a fully human anti-epidermal growth factor receptor monoclonal antibody (mAb), has demonstrated efficacy in patients with wild-type KRAS metastatic colorectal cancer (mCRC). Rilotumumab and ganitumab are investigational, fully human mAbs against hepatocyte growth factor (HGF)/scatter factor and IGF1R, respectively. Here we evaluate combining rilotumumab or ganitumab with panitumumab in previously treated patients with wild-type KRAS mCRC. Experimental Design: Part 1 was a phase Ib dose-finding study of panitumumab plus rilotumumab. The primary endpoint was the incidence of dose-limiting toxicities (DLT). Part 2 was a randomized phase II trial of panitumumab in combination with rilotumumab, ganitumab, or placebo. The primary endpoint was objective response rate (ORR); safety, progression-free survival (PFS), and overall survival (OS) were secondary endpoints. Archival tissue specimens were collected for exploratory correlative work. Results: In part 1, no DLTs were reported. A recommended phase II dose of 10 mg/kg rilotumumab was selected. In part 2, for the panitumumab plus rilotumumab (n = 48), panitumumab plus ganitumab (n = 46), and panitumumab plus placebo arms (n = 48), the ORRs were 31%, 22%, and 21%, respectively. The median PFS was 5.2, 5.3, and 3.7 months and median OS 13.8, 10.6, and 11.6 months, respectively. Adverse events were tolerable. Exploratory biomarker analyses, including MET and IGF-related protein expression, failed to indicate conclusive predictive evidence on efficacy endpoints. Conclusions: Panitumumab plus rilotumumab met the prespecified criterion for improvement in ORR whereas ganitumab did not. This is the first study to suggest a benefit for combining an HGF inhibitor (rilotumumab) with panitumumab in previously treated patients with wild-type KRAS mCRC. Clin Cancer Res; 20(16); 4240–50. ©2014 AACR.

Purpose To evaluate panitumumab plus modified fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) or bevacizumab plus mFOLFOX6 in patients with previously untreated wild-type (WT) KRAS exon 2 (codons 12 and 13) metastatic colorectal cancer (mCRC). A prespecified secondary objective was to assess treatment effects in an extended RAS analysis that included exons 2, 3, and 4 of KRAS and NRAS. Patients and Methods Patients with WT KRAS exon 2 tumors were randomly assigned at a one-to-one ratio to panitumumab plus mFOLFOX6 or bevacizumab plus mFOLFOX6. The primary end point was progression-free survival (PFS); secondary end points included overall survival (OS) and safety. Results Of 285 randomly assigned patients, 278 received treatment. In the WT KRAS exon 2 intent-to-treat group, PFS was similar between arms (hazard ratio [HR], 0.87; 95% CI, 0.65 to 1.17; P = .353). Median OS was 34.2 and 24.3 months in the panitumumab and bevacizumab arms, respectively (HR, 0.62; 95% CI, 0.44 to 0.89; P = .009). In the WT RAS subgroup (WT exons 2, 3, and 4 of KRAS and NRAS), PFS favored the panitumumab arm (HR, 0.65; 95% CI, 0.44 to 0.96; P = .029). Median OS was 41.3 and 28.9 months (HR, 0.63; 95% CI, 0.39 to 1.02; P = .058) in the panitumumab and bevacizumab arms, respectively. Treatment discontinuation rates because of adverse events were similar between arms. Conclusion PFS was similar and OS was improved with panitumumab relative to bevacizumab when combined with mFOLFOX6 in patients with WT KRAS exon 2 tumors. Patients with WT RAS tumors seemed to experience more clinical benefit with anti–epidermal growth factor receptor therapy.