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We assessed the impact of the coronavirus disease 2019 (COVID-19) pandemic on the statistical analysis of time-to-event outcomes in late-phase oncology trials. Using a simulated case study that mimics a Phase III ongoing trial during the pandemic, we evaluated the impact of COVID-19-related deaths, time off-treatment and missed clinical visits due to the pandemic, on overall survival and/or progression-free survival in terms of test size (also referred to as Type 1 error rate or alpha level), power, and hazard ratio (HR) estimates. We found that COVID-19-related deaths would impact both size and power, and lead to biased HR estimates; the impact would be more severe if there was an imbalance in COVID-19-related deaths between the study arms. Approaches censoring COVID-19-related deaths may mitigate the impact on power and HR estimation, especially if study data cut-off was extended to recover censoring-related event loss. The impact of COVID-19-related time off-treatment would be modest for power, and moderate for size and HR estimation. Different rules of censoring cancer progression times result in a slight difference in the power for the analysis of progression-free survival. The simulations provided valuable information for determining whether clinical-trial modifications should be required for ongoing trials during the COVID-19 pandemic.

The novel mechanism of action of immunotherapy agents, in treatment of various types of cancer, poses unique challenges during the designing of clinical trials. It is important to account for possibility of a delayed treatment effect and adjust sample size accordingly. This paper provides an analytical approach for computing sample size in the presence of a delayed effect using a piece-wise proportional hazards model. Failing to account for an anticipated treatment delay may result in considerable loss in power. The overall hazard ratio (HR), which now represents the average HR across the entire treatment period, can remain a meaningful measure of average benefit to patients in the trial. We show that, special consideration needs to be given for the designing of interim analyses related to futility, so as not to increase the probability of incorrectly stopping an effective agent. It is shown that the weighted log-rank test, using the Fleming-Harrington class of weights, can be used as supportive analysis to better reflect the impact of a delayed effect and possible long-term benefit in a subset of the overall population.

PD-1/PD-L1 immune checkpoint blockade (ICB) has improved overall survival (OS) in solid tumor trials; however, parallel improvements in Response Evaluation Criteria in Solid Tumors (RECIST)-based surrogate end points, progression-free survival (PFS), and objective response rate (ORR), are not always observed. Here, we assess the surrogacy of PFS/ORR for OS with ICB therapy across advanced/metastatic tumors. In a trial-level analysis (N = 40 randomized trials), PFS, ORR, and OS treatment effects were correlated (Spearman's rho). In a patient-level analysis, data were extracted from available trials of durvalumab; the correlation of PFS and OS was evaluated (Bayesian normal-induced-copula-estimation model) and the ordinal association between objective response and OS hazard ratio (HR) were assessed with concordance index measures. High correlation was observed between PFS HR and OS HR in intention-to-treat (ITT; rho = 0.76) and PD-L1-enriched populations (0.74); modest (or limited) benefit in PFS was associated with meaningful improvement in OS. Moderate correlations were observed between ΔORR and OS HR: ITT, -0.63; PD-L1-enriched, -0.53. At the patient level, a positive association was observed between PFS and OS in non-small cell lung cancer (Kendall's Tau = 0.793; 95% confidence interval, 0.789-0.797), head and neck squamous cell carcinoma (0.794; 0.789-0.798), and bladder cancer (0.872; 0.869-0.875). Objective responders had significantly better OS (concordance index > 0.9) than nonresponders across these tumor types. Modest (or limited) improvement in RECIST-based end points did not rule out meaningful OS benefit, indicating they are imperfect surrogates and do not fully capture ICB clinical benefit. Therefore, caution is advised when basing early discontinuation of novel ICB agents on these end points.

BACKGROUND: Durvalumab has shown meaningful clinical activity in patients with metastatic urothelial carcinoma (mUC) in Study 1108 (NCT01693562). An important focus in treatment is health‐related quality of life (HRQOL). Here, patient‐reported outcomes (PROs) from Study 1108 and their relationship with inflammatory biomarkers are explored. METHODS: Disease‐related symptoms, functioning, and HRQOL were assessed with the Functional Assessment of Cancer Therapy–Bladder (FACT‐Bl) and the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ‐C30). Relationships between PRO improvements and the best changes in the tumor size, albumin level, and neutrophil‐lymphocyte ratio (NLR) were assessed with Spearman correlation analysis. RESULTS: The mean FACT‐Bl total score improved from 107.5 (standard deviation [SD], 23.0) at the baseline to 115.4 (SD, 22.6) on day 113, with similar increases found for the Trial Outcome Index (TOI) and Bladder Cancer Subscale (BLCS) scores. The mean FACT‐Bl total scores improved over time, and the FACT‐Bl TOI scores significantly improved by day 113 (P < .05). The mean EORTC QLQ‐C30 Global Health Status/Quality of Life score improved from 57.1 (SD, 24.8) at the baseline to 69.0 (SD, 21.4) on day 113; the functional scale and symptom scores (day 113) were higher than the baseline scores (P < .05) for EORTC Social Functioning. The FACT‐Bl total, BLCS, and TOI scores improved in 32.6%, 34.9%, and 32.6% of the patients by day 113; 26.3% to 37.8% of the patients exhibited improvements in EORTC QLQ‐C30 functional scores. The best tumor shrinkage and posttreatment improvements in serum albumin and NLR correlated with increases in FACT‐Bl total, TOI, and BLCS scores and in EORTC Physical Functioning and Role Functioning scores (P < .05). CONCLUSIONS: Durvalumab was associated with improvements in disease‐related symptoms, functioning, and HRQOL in patients with mUC. Improvements in systemic inflammation may contribute to PRO improvements in these patients.

Background Standard parametric survival models are commonly used to estimate long-term survival in oncology health technology assessments; however, they can inadequately represent the complex pattern of hazard functions or underlying mechanism of action (MoA) of immuno-oncology (IO) treatments. Objective The aim of this study was to explore methods for extrapolating overall survival (OS) and provide insights on model selection in the context of the underlying MoA of IO treatments. Methods Standard parametric, flexible parametric, cure, parametric mixture and landmark models were applied to data from ATLANTIC (NCT02087423; data cut-off [DCO] 3 June 2016). The goodness of fit of each model was compared using the observed survival and hazard functions, together with the plausibility of corresponding model extrapolation beyond the trial period. Extrapolations were compared with updated data from ATLANTIC (DCO 7 November 2017) for validation. Results A close fit to the observed OS was seen with all models; however, projections beyond the trial period differed. Estimated mean OS differed substantially across models. The cure models provided the best fit for the new DCO. Conclusions Standard parametric models fitted to the initial ATLANTIC DCO generally underestimated longer-term OS, compared with the later DCO. Cure, parametric mixture and response-based landmark models predicted that larger proportions of patients with metastatic non-small cell lung cancer receiving IO treatments may experience long-term survival, which was more in keeping with the observed data. Further research using more mature OS data for IO treatments is needed. Electronic supplementary material The online version of this article (10.1007/s40273-019-00806-4) contains supplementary material, which is available to authorized users.

ImportanceThe log-rank test is considered the criterion standard for comparing 2 survival curves in pivotal registrational trials. However, with novel immunotherapies that often violate the proportional hazards assumptions over time, log-rank can lose power and may fail to detect treatment benefit. The MaxCombo test, a combination of weighted log-rank tests, retains power under different types of nonproportional hazards. The difference in restricted mean survival time (dRMST) test is frequently proposed as an alternative to the log-rank under nonproportional hazard scenarios.ObjectiveTo compare the log-rank with the MaxCombo and dRMST in immuno-oncology trials to evaluate their performance in practice.Data SourcesComprehensive literature review using Google Scholar, PubMed, and other sources for randomized clinical trials published in peer-reviewed journals or presented at major clinical conferences before December 2019 assessing efficacy of anti-programmed cell death protein-1 or anti-programmed death/ligand 1 monoclonal antibodies.Study SelectionPivotal studies with overall survival or progression-free survival as the primary or key secondary end point with a planned statistical comparison in the protocol. Sixty-three studies on anti-programmed cell death protein-1 or anti-programmed death/ligand 1 monoclonal antibodies used as monotherapy or in combination with other agents in 35 902 patients across multiple solid tumor types were identified.Data Extraction and SynthesisStatistical comparisons (n = 150) were made between the 3 tests using the analysis populations as defined in the original protocol of each trial.Main Outcomes and MeasuresNominal significance based on a 2-sided .05-level test was used to evaluate concordance. Case studies featuring different types of nonproportional hazards were used to discuss more robust ways of characterizing treatment benefit instead of sole reliance on hazard ratios.ResultsIn this systematic review and meta-analysis of 63 studies including 35 902 patients, between the log-rank and MaxCombo, 135 of 150 comparisons (90%) were concordant; MaxCombo achieved nominal significance in 15 of 15 discordant cases, while log-rank did not. Several cases appeared to have clinically meaningful benefits that would not have been detected using log-rank. Between the log-rank and dRMST tests, 137 of 150 comparisons (91%) were concordant; log-rank was nominally significant in 5 of 13 cases, while dRMST was significant in 8 of 13. Among all 3 tests, 127 comparisons (85%) were concordant.Conclusions and RelevanceThe findings of this review show that MaxCombo may provide a pragmatic alternative to log-rank when departure from proportional hazards is anticipated. Both tests resulted in the same statistical decision in most comparisons. Discordant studies had modest to meaningful improvements in treatment effect. The dRMST test provided no added sensitivity for detecting treatment differences over log-rank.

Combination therapies are an emerging drug development strategy in cancer, particularly in the immunooncology (IO) space. Many combination studies do not meet their safety objectives due to serious adverse events (SAEs). Prediction of SAEs based on evidence from single and combination studies would be highly beneficial. To address the emerging challenge of optimizing the safety and efficacy of combination studies, we have assembled a novel oncology clinical trial data set with 329 trials, 685 arms (279 unique treatment arms), including 200 combinations, 79 mono arms, and 59 curated adverse event categories in the setting of non-small cell lung cancer (NSCLC). We integrated the database with an analytical framework: SAEgnal. Using SAEgnal, we have investigated the difference in the risk of 39 adverse event types between combination and monotherapy arms across a subset of 34 combination trials. We observed different risk profiles between combination and monotherapies; interestingly, while the risk of elevated AST/ALT is lower in combination arms (in 1/8 trials, p-value < 0.05), it is higher for bleeding (7/8 trials, p-value < 0.05). We envisage that the SAEgnal framework would enable rapid predictive analytics of SAEs in oncology and accelerate drug development in oncology.

Background In clinical trials that assess novel therapeutic agents in patients with non-small-cell lung cancer (NSCLC), early endpoints (e.g. progression-free survival [PFS] and objective response rate) are often evaluated as indicators of biological drug activity, and are used as surrogate endpoints for overall survival (OS). Compiling trial-level data could help to develop a predictive framework to ascertain correlation trends between treatment effects for early (e.g. odds ratio [OR] for PFS at 6 months) and late endpoints (e.g. hazard ratio [HR] OS). Methods A dataset was compiled, which included 81 randomized, controlled trials (RCTs; Phase II–IV) of NSCLC (Stages I–IV), with 35 drugs and 156 observations. The dataset was collected from multiple source databases, including Citeline, TrialTrove, clinicaltrials.gov, and PubMed. We applied random-effects meta-analysis to correlate a variety of treatment effects for early endpoints with HR OS. We performed meta-regression analyses across different data-strata, stratified by the mechanism of action (MoA) of the investigational product (programmed death protein-1/programmed death-ligand 1 [PD-1/PD-L1], epidermal growth factor receptor [EGFR], vascular endothelial growth factor receptor, and DNA damage response). Results Low (Spearman’s rho 0.3– 1, indicate benefit with the investigational product. Conclusions Using a comprehensive summary data set in the NSCLC space, we observed low-to-moderate correlations between treatment effects for early endpoints and HR OS across RCTs of agents with different MoAs, including trials of PD-1/PD-L1 checkpoint inhibitors. Exploration of additional endpoints, beyond RECIST, is required to identify other early indicators of efficacy that might predict HR OS. By incorporating additional trial-level parameters and building composite biomarkers using machine intelligence methods, in collaboration with innovative trial design efforts, we envisage to improve the prediction of HR OS from early endpoints.

Durvalumab is an anti-PD-L1 monoclonal antibody approved for patients with locally advanced or metastatic urothelial carcinoma (UC) that has progressed after platinum-containing chemotherapy. A population tumor kinetic model, coupled with dropout and survival models, was developed to describe longitudinal tumor size data and predict overall survival in UC patients treated with durvalumab (NCT01693562) and to identify prognostic and predictive biomarkers of clinical outcomes. Model-based covariate analysis identified liver metastasis as the most influential factor for tumor growth and immune-cell PD-L1 expression and baseline tumor burden as predictive factors for tumor killing. Tumor or immune-cell PD-L1 expression, liver metastasis, baseline hemoglobin, and albumin levels were identified as significant covariates for overall survival. These model simulations provided further insights into the impact of PD-L1 cutoff values on treatment outcomes. The modeling framework can be a useful tool to guide patient selection and enrichment strategies for immunotherapies across various cancer indications.

We would like to thank the authors of the letter (Bartlett et al. 2020) for sharing their concerns regarding reporting treatment effect under nonproportional hazards (NPH), and we respect their pos...

BackgroundStudies have indicated that programmed death ligand 1 (PD-L1) expression may have utility as a predictive biomarker in patients with advanced/metastatic urothelial carcinoma (UC). Different immunohistochemical (IHC) assays are in development to assess PD-L1 expression on tumor cells (TCs) and tumor-infiltrating immune cells (ICs).MethodsIn this post hoc analysis of the single-arm, phase 1/2 Study 1108 (NCT01693562), PD-L1 expression was evaluated from tumor samples obtained prior to second-line treatment with durvalumab in patients with advanced/metastatic UC using the VENTANA (SP263) IHC Assay. The primary objective was to determine whether the TC ≥ 25%/IC ≥ 25% algorithm (i.e., cutoff of ≥ 25% TC or ≥ 25% IC with PD-L1 staining at any intensity above background) was optimal for predicting response to durvalumab. PD-L1 expression data were available from 188 patients.ResultsAfter a median follow-up of 15.8 and 14.6 months, higher PD-L1 expression was associated with longer overall survival (OS) and progression-free survival (PFS), respectively, with significant separation in survival curves for PD-L1-high and-low expressing patients for the TC ≥ 25%/IC ≥ 25% cutoff (median OS: 19.8 vs 4.8 months; hazard ratio: 0.46; 90% confidence interval: 0.33, 0.639). OS was also prolonged for PD-L1-high compared with-low patients when samples were categorized using TC/IC combined positive score ≥ 10 and IC≥ 5% cutoffs. In multivariate analysis, IC but not TC PD-L1 expression was significantly associated with OS, PFS, and objective response rate (P < 0.001 for each), although interaction analysis showed similar directionality of benefit for ICs and TCs.ConclusionsThese findings support the utility of a combined TC/IC algorithm for predicting response to durvalumab in patients with UC, with the TC≥ 25%/IC≥ 25% cutoff optimal when used with the VENTANA (SP263) IHC Assay.

Introduction Two clinical studies (Study 1108 and ATLANTIC) were analyzed to evaluate the prognostic value of baseline liver metastases (LMs) in advanced/metastatic non–small-cell lung cancer patients treated with durvalumab 10 mg/kg every 2 weeks. Patients and Methods A multivariate Cox proportional hazards analysis was conducted; covariates included performance status, tumor stage, histology, sex, age, smoking status, and programmed cell death ligand 1 (PD-L1) status. Results In all, 569 patients were included. LMs were present in 31.6% (96/304) of Study 1108 patients and 17.9% (47/263) of ATLANTIC patients. Median overall survival (OS) was shorter in patients with LMs than in those without in both studies. In both studies, LMs were an independent negative prognostic factor for OS and progression-free survival. Objective response rates were also significantly lower. PD-L1 independently predicted benefit across all patients. Conclusion Liver metastases were associated with worse outcomes irrespective of PD-L1 status, but PD-L1 status predicted benefit from durvalumab irrespective of LMs.

Objective The purpose of this multicenter, open label, randomized phase III study was to determine whether ixabepilone resulted in improved overall survival (OS) compared with commonly used single-agent chemotherapy (doxorubicin or paclitaxel) in women with locally advanced, recurrent, or metastatic endometrial cancer with at least one failed prior platinum-based chemotherapeutic regimen. Methods Patients were randomized 1:1 to ixabepilone (40mg/m 2 ), or either paclitaxel (175mg/m 2 ) or doxorubicin (60mg/m 2 ), every 21days. Patients that had previously received an anthracycline were randomized to ixabepilone or paclitaxel; all other patients were randomized to ixabepilone or doxorubicin. An interim analysis of futility for OS was planned. Results At the time of database lock, 496 patients were randomized to receive ixabepilone (n=248) or control (n=248); nine patients in the control arm were not treated. The interim analysis of futility for OS (219 events) favored the control chemotherapy arm (hazard ratio=1.3 [95% confidence interval: 1.0–1.7], stratified log rank test P=0.0397), indicating that the study would not meet its primary objective. The study was discontinued based on the interim OS results. The frequency of adverse events was comparable between the treatment arms. Conclusions The study did not meet its primary objective of improving OS in the ixabepilone arm compared to the control chemotherapy arm. A favorable risk/benefit ratio was not observed for ixabepilone versus control at the time of the interim analysis. The safety results were consistent with the known safety profiles of ixabepilone and control.

Background Despite high initial sensitivity to chemotherapy, TNBC is associated with a poor prognosis, highlighting the need for novel therapeutic strategies. The aim of this multicenter, randomized, open-label phase II trial was to assess the efficacy of ixabepilone as monotherapy, and the combination of ixabepilone with cetuximab, as first-line treatment in patients with triple-negative locally advanced nonresectable and/or metastatic breast cancer. Patients and Methods Women were randomly assigned to receive either ixabepilone (40 mg/m 2 ) every 21 days (n = 40), or ixabepilone (40 mg/m 2 ) every 21 days with cetuximab (400 mg/m 2 loading dose, followed by 250 mg/m 2 ) once weekly (n = 39). The primary end point of the trial was to estimate the response rates of ixabepilone monotherapy and ixabepilone with cetuximab combination therapy. Results Of 79 randomized patients, 77 were treated. Based on an intent-to-treat analysis, an objective response rate of 30% (95% confidence interval [CI], 16.6-46.5) was observed in the monotherapy arm, and 35.9% (95% CI, 21.2-52.8) in the combination arm. Median progression-free survival was 4.1 months in both treatment groups. Safety findings were consistent with the known individual toxicity profiles of ixabepilone and cetuximab. Skin and subcutaneous tissue disorders were more common with combination therapy, as were discontinuations because of adverse events. Conclusion Ixabepilone monotherapy and the ixabepilone and cetuximab combination demonstrated similar levels of clinical activity in first-line treatment of advanced TNBC, with a predictable safety profile. Further investigation of novel therapies for TNBC is required to improve patient outcomes.

The objectives of this analysis were to develop a population pharmacokinetics (PK) model of durvalumab, an anti-PD-L1 antibody, and quantify the impact of baseline and time-varying patient/disease characteristics on PK. Pooled data from two studies (1,409 patients providing 7,407 PK samples) were analyzed with nonlinear mixed effects modeling. Durvalumab PK was best described by a two-compartment model with both linear and nonlinear clearances. Three candidate models were evaluated: a time-invariant clearance (CL) model, an empirical time-varying CL model, and a semimechanistic time-varying CL model incorporating longitudinal covariates related to disease status (tumor shrinkage and albumin). The data supported a slight decrease in durvalumab clearance with time and suggested that it may be associated with a decrease in nonspecific protein catabolic rate among cancer patients who benefit from therapy. No covariates were clinically relevant, indicating no need for dose adjustment. Simulations indicated similar overall PK exposures following weight-based and flat-dosing regimens.

Background PD-L1 expression determined by immunohistochemistry (IHC) can be a useful biomarker to assess the likelihood of benefit with anti-PD-1/PD-L1 therapies in pts with mNSCLC. Understanding the impact of sample type (primary tumour or metastatic) on predictivity of benefit will inform the suitability of such samples for clinical testing. MYSTIC (NCT02453282) was an open-label, phase III study of durvalumab (D) ± tremelimumab vs chemotherapy (CT) as first-line treatment for mNSCLC; stratification factors for randomisation included tumour cell (TC) PD-L1 expression (≥25% vs Methods All pts enrolled in MYSTIC were assessed centrally for TC staining for PD-L1 from tissue samples acquired Results Of 1118 pts randomised, 716 (64.0%) provided a primary tumour sample and 402 (36.0%) provided a metastatic sample. The prevalence of PD-L1 TC ≥25% assessed using primary vs metastatic samples was 43.0% vs 44.8% (p = 0.569). Outcomes in pts with TC ≥ 25% determined using samples of each type are shown. Table . 1491P Primary tumour sample PD-L1 TC ≥25% Metastatic sample PD-L1 TC ≥25% Durvalumab (n = 104) Chemotherapy (n = 100) Durvalumab (n = 59) Chemotherapy (n = 62) Median OS, months 15.8 13.0 20.5 12.9 HR for OS vs CT (95% CI) 0.81 (0.59–1.11) - 0.65 (0.41–1.01) - 24-month OS, % 33.4 19.1 46.9 28.6 ORR, % 30.8 37.0 44.1 38.7 Median DoR, months Not reached 4.4 Not reached 4.1 Conclusions In MYSTIC, PD-L1 TC ≥25% prevalence was similar using primary or metastatic samples. Favourable HRs for OS with D vs CT were seen in pts with TC ≥ 25% expression as determined in either the primary tumour or a metastatic site. Results should be interpreted with caution given the retrospective nature of the analysis. Clinical trial identification NCT02453282 (release date: 25 May 2015). Editorial acknowledgement Samantha Holmes, PhD, of Cirrus Communications (Macclesfield, UK), an Ashfield company, funded by AstraZeneca and in accordance with Good Publication Practice (GPP3) guidelines. Legal entity responsible for the study AstraZeneca PLC. Funding AstraZeneca. Disclosure N. Reinmuth: Honoraria (self), Travel / Accommodation / Expenses: BMS; Honoraria (self), Travel / Accommodation / Expenses: AstraZeneca; Honoraria (self), Travel / Accommodation / Expenses: Bohringer Ingelheim; Honoraria (self), Travel / Accommodation / Expenses: Roche; Honoraria (self), Travel / Accommodation / Expenses: MSD; Honoraria (self), Travel / Accommodation / Expenses: Takeda; Honoraria (self): Pfizer. A. Boothman: Shareholder / Stockholder / Stock options, Full / Part-time employment: AstraZeneca. B.C. Cho: Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (self): Novartis; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self): AstraZeneca; Advisory / Consultancy: Boehringer Ingelheim; Advisory / Consultancy: Roche; Advisory / Consultancy: BMS; Advisory / Consultancy, Research grant / Funding (self): Ono; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self): Yuhan; Advisory / Consultancy: Pfizer; Advisory / Consultancy: Eli Lilly; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self): Janssen; Speaker Bureau / Expert testimony: Takeda; Advisory / Consultancy: MSD; Shareholder / Stockholder / Stock options: TheraCanVac Inc; Honoraria (self), Research grant / Funding (self): Bayer; Honoraria (self), Research grant / Funding (self): MOGAM Institute; Honoraria (self), Research grant / Funding (self): Dong-A ST; Honoraria (self), Research grant / Funding (self), Licensing / Royalties: Champions Oncology; Honoraria (self), Research grant / Funding (self): Dizal Pharma; Honoraria (self), Research grant / Funding (self): MSD. K.H. Lee: Research grant / Funding (institution): AstraZeneca. M. Ahn: Advisory / Consultancy, Research grant / Funding (institution), Spouse / Financial dependant: AstraZeneca; Advisory / Consultancy, Research grant / Funding (institution): AbbVie; Advisory / Consultancy, Research grant / Funding (institution): Amgen; Research grant / Funding (institution): BIND Biosciences; Research grant / Funding (institution): Celgene; Research grant / Funding (institution): Eli Lilly; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): MedImmune; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): Pfizer. M. Scott: Shareholder / Stockholder / Stock options, Full / Part-time employment: AstraZeneca. J. Whiteley: Shareholder / Stockholder / Stock options, Full / Part-time employment: AstraZeneca. J. Walker: Full / Part-time employment: AstraZeneca. V. Karwe: Full / Part-time employment: AstraZeneca. P. Mukhopadhyay: Shareholder / Stockholder / Stock options, Full / Part-time employment: AstraZeneca. P. Thiyagarajah: Full / Part-time employment: AstraZeneca. U. Scheuring: Full / Part-time employment: AstraZeneca. N. Rizvi: Advisory / Consultancy: AstraZeneca; Advisory / Consultancy: Merck; Advisory / Consultancy: Roche; Advisory / Consultancy: Bristol-Myers Squibb; Advisory / Consultancy: Novartis; Advisory / Consultancy: Pfizer; Advisory / Consultancy: Lilly; Advisory / Consultancy: AbbVie; Advisory / Consultancy: Merck KGaA; Advisory / Consultancy: Regeneron; Shareholder / Stockholder / Stock options: Gritstone Oncology; Shareholder / Stockholder / Stock options: ARMO Biosciences. All other authors have declared no conflicts of interest.

This multicenter, open-label, randomized phase II trial compared the efficacy and tolerability of weekly ixabepilone versus the standard 3 weekly dosing regimen. Patients with human epidermal growth factor receptor 2-negative, metastatic breast cancer (MBC) were randomly assigned to receive either ixabepilone 16 mg/m(2) as a 1-h intravenous (IV) infusion weekly on days 1, 8, and 15 of a 28-day cycle (1 week off therapy; n = 85), or 40 mg/m(2) as a 3-h IV infusion on day 1 of a 21-day cycle (n = 91), until disease progression or unacceptable toxicity. Randomization was stratified by (i) measurable versus nonmeasurable (evaluable) disease, (ii) ≤two versustwo prior chemotherapy regimens for MBC, and (iii) hormone receptor (HR)-positive versus HR-negative breast cancer. The primary endpoint was rate of progression-free survival (PFS) at 6 months. Of 176 randomized patients, 171 were treated. The 6-month PFS rate was significantly higher in patients treated with ixabepilone every 3 weeks (42.7, 95 % confidence interval [CI] 31.5-53.5) compared with those who received ixabepilone weekly (28.6, 95 % CI 18.9-38.9; log-rank P = 0.03). Every-3-week dosing significantly prolonged median PFS versus weekly dosing (5.3 vs. 2.9 months; log-rank P = 0.05). The every-3-week regimen was associated with higher rates of grade 3/4 toxicities, particularly neutropenia (38.2 vs. 6.1 %) and a higher rate of patient withdrawal due to adverse events. These results suggest that every-3-week ixabepilone is more effective than weekly treatment in MBC, albeit with more toxicity.

Background. This randomized phase II trial was designed to compare the rate of pathologic complete response (pCR) induced by neoadjuvant cyclophosphamide plus doxorubicin (AC) followed by ixabepilone or paclitaxel in women with early stage breast cancer (BC). Expression of βIII-tubulin as a predictive marker was also evaluated. Patients and Methods. Women with untreated, histologically confirmed primary invasive breast adenocarcinoma received four cycles of AC followed by 1:1 randomization to either ixabepilone 40 mg/m2 (3-hour infusion) every 3 weeks for four cycles (n = 148) or weekly paclitaxel 80 mg/m2 (1-hour infusion) for 12 weeks (n = 147). All patients underwent a core needle biopsy of the primary cancer for molecular marker analysis prior to chemotherapy. βIII-Tubulin expression was assessed using immunohistochemistry. Results. There was no significant difference in the rate of pCR in the ixabepilone treatment arm (24.3%; 90% confidence interval [CI], 18.6–30.8) and the paclitaxel treatment arm (25.2%; 90% CI, 19.4–31.7). βIII-Tubulin-positive patients obtained higher pCR rates compared with βIII-tubulin-negative patients in both treatment arms; however, βIII-tubulin expression was not significantly associated with a differential response to ixabepilone or paclitaxel. The safety profiles of both regimens were generally similar, although neutropenia occurred more frequently in the ixabepilone arm (grade 3/4: 41.3% vs. 8.4%). The most common nonhematologic toxicity was peripheral neuropathy. Conclusions. Neoadjuvant treatment of early stage BC with AC followed by ixabepilone every 3 weeks or weekly paclitaxel was well tolerated with no significant difference in efficacy. Higher response rates were observed among βIII-tubulin-positive patients.

The therascreen KRAS RGQ polymerase chain reaction kit is being developed as a companion diagnostic to aid clinicians, through detection of KRAS mutations, in the identification of patients with metastatic colorectal cancer (mCRC) who are more likely to benefit from cetuximab.To assess whether KRAS mutation status, determined by using the therascreen KRAS kit, is a predictive marker of cetuximab efficacy.Tissue samples were obtained from patients with mCRC treated on the National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) CO.17 phase 3 study of cetuximab plus best supportive care (BSC) versus BSC alone. Tumor DNA samples were assessed for the presence of KRAS mutations by using the therascreen KRAS kit. Efficacy and safety were assessed to determine whether mutation status was predictive of outcomes. Results.-Evaluable samples were available from 453 patients (79.2%) enrolled in the NCIC CTG CO.17 trial. The KRAS wild-type subset represented 54.1% (245 of 453) of the evaluated population. Median overall survival of patients with KRAS wild-type tumors was 8.6 months among those who received cetuximab plus BSC and 5.0 months among patients who received BSC alone (hazard ratio [HR], 0.63; P = .002). Among patients with KRAS mutant mCRC, no meaningful difference in overall survival was observed between arms (HR, 0.91; P = .55). These results are consistent with a previous report that analyzed patient tumor samples by using bidirectional sequencing.These data support the utility of the therascreen KRAS kit as a means of selecting patients who may benefit from cetuximab therapy.

Background This retrospective analysis aimed to determine whether early dose reduction impacts the efficacy of ixabepilone plus capecitabine in women with metastatic breast cancer (MBC). Patients and Methods In 2 phase III trials, patients (N = 1973) with anthracycline/taxane–pretreated MBC were randomized to receive ixabepilone 40 mg/m 2 on day 1 plus capecitabine 1000 mg/m 2 twice daily (BID) on days 1 to 14 or single-agent capecitabine 1250 mg/m 2 BID on days 1 to 14 of a 3-week course. Because of the similar design and populations, data from trials were pooled to evaluate efficacy of the combination regimen among women who did or did not undergo ixabepilone dose reduction during the first 4 courses. To adjust for bias resulting from selecting patients with inherently better outcome based on longer treatment durations, these analyses were restricted to patients who received ≥ 4 courses of ixabepilone. Results The pooled cohort included 566 patients with measurable disease who were evaluable for efficacy. Patients who had early dose reduction showed similar objective response rates (ORRs) and progression-free survival (PFS) as did those with no/late dose reduction. ORRs were 62.6% (95% confidence interval [CI], 55.8%-69.0%) and 55.3% (95% CI, 49.9%-60.6%), respectively; median PFS was 7.2 months (95% CI, 6.6-8.0) and 7.0 months (95% CI, 6.5-7.5), respectively (hazard ratio=0.98; 95% CI, 0.83-1.17). Conclusion These data suggest that early ixabepilone dose reduction did not affect the overall efficacy of ixabepilone plus capecitabine in patients with MBC who received ≥ 4 courses of treatment. By making appropriate dose reductions, ixabepilone-related toxicities can be minimized while maintaining clinical efficacy.

Purpose Dose-limiting neuropathy is a major adverse event associated with most of the microtubule-stabilizing agent-based chemotherapy regimens. Ixabepilone, a semisynthetic analogue of the natural epothilone B, has activity against a wide range of tumor types. Peripheral neuropathy (PN), associated with ixabepilone treatment, is usually mild to moderate, predominantly sensory and cumulative. Preclinical studies demonstrate that ixabepilone and taxanes produce a similar neurotoxicity profile. Methods We searched databases of phase II/III clinical trials involving patients receiving ixabepilone as a monotherapy or in combination with capecitabine for incidences of neuropathy. Potential risk factors for grade 3/4 PN were identified by a Cox regression analysis on a dataset of 1,540 patients with different tumor types across multiple studies. Results Rates for incidence of ixabepilone-induced severe PN (Common Terminology Criteria for Adverse Events grade 3/4) ranged from 1% in early untreated breast cancer up to 24% in heavily pretreated metastatic breast cancer; grade 4 PN was rare (≤1%). Common symptoms included numbness, paresthesias, and sometimes dysesthesias. Cox regression analysis identified only preexisting neuropathy as a risk factor for increased ixabepilone-associated PN. The management of PN has been primarily through dose adjustments (dose delays and/or dose reduction). Patients had resolution of their neuropathy within a median time of 5 to 6 weeks. Conclusions PN is a dose-limiting toxicity associated with ixabepilone treatment, is reversible in most patients, and can be managed with dose reduction and delays. Electronic supplementary material The online version of this article (doi:10.1007/s00520-012-1384-0) contains supplementary material, which is available to authorized users.

Background: The mTOR pathway is constitutively activated in hormone-resistant advanced breast cancer (ABC). In phase II trials, everolimus (EVE) showed promising efficacy both as monotherapy and in combination with endocrine therapy in patients with estrogen receptor-positive (ER+) ABC. This double-blind, placebo-controlled, phase III study evaluated EVE plus exemestane (EXE) in patients with ER+ ABC refractory to letrozole or anastrozole. Patients and Methods: Eligible patients were randomized (2:1) to EXE (25 mg/day) with EVE (10 mg/day) or with matching placebo. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival, response rate, quality of life (QoL), and safety. Results: 724 patients were randomized (485: EVE+EXE; 239: EXE). Baseline characteristics were well balanced; median age was 62 years, 56% had visceral involvement, and 84% had documented benefit from previous endocrine therapy, which included letrozole or anastrozole (100%), tamoxifen (48%), fulvestrant (16%), and chemotherapy for advanced disease (25%). This analysis is based on 457 events and median follow-up of 12.5 months. PFS by investigator assessment showed a hazard ratio (HR) of 0.44 (95% CI: 0.36−0.53) and a median duration of 7.4 (EVE+EXE) vs 3.2 months (EXE) (P The most common grade 3/4 adverse events were stomatitis (8% vs 1%), anemia (7% vs 1%), hyperglycemia (5% vs < 1%), dyspnea (4% vs 1%), and fatigue (4% vs 1%) for the EVE+EXE and EXE groups, respectively. Grade 3 pneumonitis was observed in patients receiving EVE (3% vs 0%). No difference in time to deterioration of QoL was observed. EVE increased EXE steady-state Cmin and Cmax levels by 45% and 64%, respectively, with no difference in estradiol levels. Serum markers of bone resorption and bone formation increased in the EXE arm and generally decreased in the EVE+EXE arm. Conclusion: The addition of EVE to EXE is associated with significant and sustained prolongation of PFS. Adverse events were higher in the combination arm but manageable by dose interruption and/or reduction and did not affect QoL. EVE in combination with an aromatase inhibitor is a promising therapeutic option for women with hormone receptor-positive advanced breast cancer. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr S3-7.

BACKGROUND: Combination therapy with ixabepilone and capecitabine (cape) is approved for use in patients with locally advanced/metastatic breast cancer that is resistant to treatment with anthracyclines or taxanes. The current study evaluated the trade-off between quality and quantity of life using quality-adjusted time without symptoms or toxicity (Q-TWiST) outcomes. METHODS: Within the trial, 752 women were randomly assigned to receive either the combination of ixabepilone and cape (once every 21 days) or cape alone (on days 1-14). The area under the survival curve was partitioned into 3 health states: toxicity (TOX), time without symptoms of disease progression or toxicity, and recurrence (relapse [REL]). The mean time in each health state was weighted by a range of utilities and summed to estimate quality-adjusted survival (QAS). Patient-reported outcomes were also evaluated using the Functional Assessment of Cancer Therapy (FACT)-Breast Symptom Index (FBSI). RESULTS: A statistically significant difference between groups with regard to change from baseline FBSI scores favoring the cape group was observed (P = .0002), but no differences were observed after adjusting for deaths in the analysis. All combinations of utilities for REL and TOX resulted in an observed difference in QAS favoring combination therapy. Differences were found to be statistically significant for comparisons, with higher tolerance for TOX. QAS was found to be greater for the combination therapy group (42.2 weeks vs 38.4 weeks), assuming the base case scenario of utility equal to 0.5 for both TOX and REL (P = .0227). CONCLUSIONS: The Q-TWiST analysis supports a positive benefit-risk ratio for the combination of ixabepilone plus cape in patients with advanced/metastatic breast cancer that is refractory to anthracyclines and taxanes versus cape alone, despite the potential for added toxicities with combination therapy. Cancer 2011;. © 2011 American Cancer Society.

3028Background: Although PD-1/PD-L1 checkpoint blockade has become standard of care for non-small cell lung cancer (NSCLC), some treated patients (pts) do not respond. A deeper understanding of mechanisms of resistance to PD-(L)1 blockade is needed to improve therapeutic decisions. The aim of this study was to identify molecular alterations associated with innate resistance to durvalumab (D) and durvalumab + tremelimumab (D + T) combination therapy in advanced non-squamous (Non-SQ) NSCLC. Methods: CP1108/NCT01693562 and ATLANTIC/NCT02087423 were nonrandomized phase 1/2 and 2 trials of D (10 mg/kg, Q2W). D4190C00006/NCT02000947 was a nonrandomized phase Ib trial of D + T (20 mg/kg + 1 mg/kg, Q4W). Circulating tumor DNA (ctDNA) analysis (Guardant360 70 gene cancer panel) was conducted in pre-treatment plasma samples for 119 and 63 Non-SQ NSCLC pts in CP1108 and ATLANTIC, respectively. Targeted sequencing of pre-treatment tumors (FoundationOne CDx™) was conducted in 120 Non-SQ NSCLC pts in D4190C00006. Assoc...

4532Background: In Study 1108, durvalumab showed meaningful clinical activity in patients with UC, with an objective response rate (ORR) of 17.8% (PD-L1–positive patients: 27.6%) [Powles 2017, JAMA...

4530Background: PD-L1 expression is a useful biomarker in predicting response to PD-1 and PD-L1 directed immunotherapies in a variety of tumor types. In UC, studies have implicated PD-L1 expression...

2566 Background: Durvalumab is a human monoclonal antibody that binds to PD-L1 and blocks its interaction with PD-1 and CD80. The objectives of this analysis were to develop a population pharmacokinetics (PK) model of durvalumab, to quantitate the effect of patient/disease characteristics on PK, and to compare weight (WT)-based versus fixed dosing regimens. Methods: Data were pooled from two studies: Study 1108 (Phase 1/2; various tumor types) and ATLANTIC (Phase 2; NSCLC). A total of 1324 patients provided data following 0.1 to 20 mg/kg IV durvalumab. The population PK was performed using a non-linear mixed effects modeling approach in NONMEM software. The impact of demographics, clinical indices, and biomarkers on PK was explored. Results: Durvalumab PK was best described using a 2-compartment model with both linear and non-linear clearances. The mean (between-patient variability) linear clearance (CL) and central volume of distribution (V1) were 226 mL/day (~29%) and 3.51 L (~21%), respectively. Although population PK analysis identified a few statistically significant covariates (WT, sex, CrCL, post-baseline ADA, ECOG performance status, LDH, sPDL1 levels, tumor type, and albumin), none were found to be clinically relevant (effect on PK parameters < 30%), indicating no need for dose adjustment. Simulations indicated similar overall PK exposures following WT-based (10 mg/kg Q2W) and fixed dosing regimens (1500 mg Q4W or 750 mg Q2W); with all regimens expected to maintain target trough exposure of ~50 µg/mL in ≥95% patients. In a post-hoc analysis, durvalumab clearance was found to decrease slightly over time, with a mean maximal reduction from baseline value of 15.5%. The decrease in CL was associated with tumor shrinkage, decreased LDH, increased albumin and decreased neutrophil to lymphocyte ratio. The small decrease in CL was not considered relevant to PK exposure or dosing. Conclusions: A population PK model of durvalumab was developed and validated. No dose adjustments were needed based on any patient or disease characteristics. The analysis demonstrated the feasibility of switching to a fixed dose regimen. Clinical trial information: NCT02087423 and NCT01693562.

11555 Background: Durvalumab is a human monoclonal antibody that binds to PD-L1 and blocks its interaction with PD-1 and CD80. The primary objectives of this analysis were to describe the longitudinal tumor size profiles and identify the key factors predicting tumor growth and regression following durvalumab. Methods: Longitudinal tumor size data obtained from NSCLC patients in study 1108 (all lines of therapy) and ATLANTIC (third line and beyond) following durvalumab treatment were modeled using nonlinear mixed effect modeling. Tumor kinetics were described by four key parameters: tumor growth and killing rate constants, fraction of durvalumab-sensitive tumor cells, and delay time for tumor killing. Potential predictive factors for tumor growth and regression were evaluated in a multi-variable covariate analysis. The model was used to simulate response rates at different tumor PD-L1 expression cutoffs. Results: Tumor kinetic modeling accurately described the longitudinal tumor response profiles from NSCLC patients in both studies. The factors associated with more rapid tumor growth were liver metastases, ECOG score > 0, high neutrophil-to-lymphocyte ratio and EGFR/ALK mutation. Tumor cell PD-L1 expression, baseline tumor size and smoking history were identified as significant predictive factors for tumor killing or the fraction of sensitive tumor cells. Simulations using the tumor kinetic model showed increased response rates in patients with higher tumor cell PD-L1 expression (increased by 9-11% and 10-14% with 25% and 50% cutoff, respectively), patients receiving durvalumab as first-line therapy (increased by 12% vs. 2nd line/above), and patients with smoking histories (increased by 4-5% vs. non-smokers). Conclusions: Tumor kinetic modeling identified factors that predict tumor progression and response following durvalumab in NSCLC patients. The multivariate analysis accounts for various predictive factors within predictive biomarker strata, allowing better interpretation of different biomarker cutoffs. The modeling technique can potentially guide patient selection/enrichment, clinical trial design strategies and tumor biology. Clinical trial information: NCT02087423 and NCT01693562.

3035 Background: Progression of cancer is often associated with biomarkers of cancer inflammation, cachexia, and increased protein catabolism. Anti-PD1 and PD-L1 therapy have demonstrated durable responses across a number of tumor types. Durvalumab is a human monoclonal antibody that binds to PD-L1 and blocks its interaction with PD-1 and CD80. The primary objective of this analysis was to prospectively assess potential correlations of longitudinal changes in ALB and NLR and durvalumab clearance (CL) rate to maximum decrease in tumor size and overall survival (OS) in patients (pts) with NSCLC and UC receiving durvalumab. Methods: Longitudinal target lesion size, serum chemistry, hematology and pharmacokinetic data were obtained from 3L+ NSCLC pts (n = 418) in study ATLANTIC and 2L+ UC pts (n = 182) in study 1108 during durvalumab treatment. Nonparametric correlations (Spearman’s rho) were evaluated between OS, maximum percent change in target lesion size, and the maximum percent change from baseline observed in ALB, NLR, and CL. Results: In NSCLC, maximum decrease in tumor size was correlated with increased ALB (r = 0.46, p < 0.0001), decreased NLR (r = 0.44, p < 0.0001), and decreased CL (r = 0.66, p < 0.0001). OS was similarly correlated with increased ALB (r = 0.47, p < 0.0001), decreased NLR (r = 0.41, p < 0.0001), and decreased CL (r = 0.76, p < 0.0001). In UC, decreased tumor size also correlated with increased ALB (r = 0.43, p < 0.0001), decreased NLR (r = 0.38, p < 0.0001), and decreased CL (r = 0.65, p < 0.0001). OS in UC also correlated with increased ALB (r = 0.50, p < 0.0001), decreased NLR (r = 0.33, p < 0.0001) and decreased CL (r = 0.82, p < 0.0001). Conclusions: In NSCLC and UC pts receiving durvalumab, tumor shrinkage and longer survival are associated with increased ALB, decreased NLR and decreased clearance of durvalumab. These findings support the hypothesis that durvalumab may be associated with a decrease in protein catabolism, inflammation and cachexia among pts who benefited from therapy. Additional biomarkers of cancer, inflammation and cachexia will be evaluated for relationships to clinical outcomes.

3038 Background: Immunotherapies have improved survival in NSCLC but not all pts benefit. Besides baseline PDL1 expression, routinely measured clinical factors may predict clinical outcomes in immunotherapy trials. LM are associated with poor prognosis in melanoma and bladder cancer pts treated with anti-PD1/L1, respectively. We examined correlation between pretreatment LM and survival in D-treated NSCLC pts. Methods: CP1108/NCT01693562 and ATLANTIC/NCT02087423 were nonrandomized phase 1/2 and 2 trials, respectively, of D 10 mg/kg Q2W in advanced NSCLC. As of Oct 24/Jun 3 2016, 304/265 primarily pretreated pts were enrolled in CP1108/ATLANTIC Cohort 2. Cox proportional hazards analysis was conducted, first among LM+/− pts, then LM+/− and PDL1 high/low pts. Both models accounted for tumor stage, ECOG/WHO PS, histology, sex, age, smoking and PDL1 status. PDL1 high was defined as ≥25% tumor cells immunostained for PDL1 at any intensity. Results: LM absence was a positive independent predictor of OS and PFS in both trials. LM− and PDL1 high or low pts had improved OS and PFS vs PDL1 low/LM+; PDL1 high/LM+ pts had improved PFS vs PDL1 low/LM+. An independent tumor kinetic model indicated LM as a predictive covariate of rapid tumor growth in D-treated pts. Conclusions: LM are associated with shorter survival in D-treated NSCLC pts in 2 trials irrespective of PDL1 status. Clinical trial information: NCT02087423 and NCT01693562. [Table: see text]

2568 Background: Durvalumab is a human monoclonal antibody that binds to PD-L1 and blocks its interaction with PD-1 and CD-80. The objective of this analysis was to evaluate the relationship between durvalumab PK exposure with efficacy and safety following 10 mg/kg Q2W durvalumab. Methods: Data from Study 1108 (Phase 1/2; all tumor types) and ATLANTIC (Phase 2; NSCLC) were used for exposure-safety analysis for Study 1108 UC cohort, Study 1108 all patients and ATLANTIC patients, respectively, whereas the exposure-efficacy analysis was performed using data from Study 1108 UC cohort. The observed PK exposure metrics included PK concentrations after the first, second or steady state doses. Efficacy endpoints used were objective response rate (ORR) and best percentage change in target lesion from baseline per BICR assessment. Safety endpoints included Grade 3+ AE (any AE, drug-related AE, AESI, and drug-related AESI) and AE leading to treatment discontinuation. Results: Overall, no association of PK exposure with efficacy or safety was observed. Distribution of PK metrics were similar between responders and non-responders. The probability of objective response was similar in all quartiles of exposure (p-value ranged from 0.37 to 0.67; n = 96) with no obvious trends between PK exposures and change in tumor size. For Grade 3+ AE (all types) and AE leading to treatment discontinuation, higher PK exposure was not associated with an increased risk of AE (p-value ranged from < 0.00005 to 0.88; n = 158, 929 and 434 for 1108 UC cohort, 1108 all patients and ATLANTIC all patients, respectively). A few inverse trends were observed, likely due to confounding effect of ECOG or albumin since covariate analysis demonstrated that both variables correlated with PK and AEs. In addition, the association of ECOG and albumin versus PK exposure were also observed in the population PK modeling. Conclusions: The exposure-efficacy and exposure-safety analyses suggested that 10 mg/kg IV Q2W regimen was an appropriate dose for durvalumab as single agent in UC patients. Overall, no relationship of PK exposure with either the efficacy or safety was observed following 10 mg/kg IV Q2W regimen. Clinical trial information: NCT02087423 and NCT01693562.

Background: Demonstrating improved overall survival (OS) with new multiple myeloma (MM) treatments is becoming difficult because of extended survival, so progression-free survival (PFS) is commonly used as a surrogate endpoint for OS. We evaluated PFS as a potential surrogate for OS by examining whether observed treatment effects on PFS are positively associated with treatment effects on OS in MM. Methods: A systematic literature review identified 21 randomized control trials reporting hazard ratios (HRs) for treatment effects on PFS and OS. Pearson's r estimated the relationship between HRs (HRPFS and HROS), and between log-transformed HRs (log(HRPFS) and log(HROS)). R2 values were estimated from linear regression models of the HR and the log(HR) relationships. Sensitivity and subgroup analyses examined the robustness of the HR findings. Results: Positive correlations were found between HRPFS and HROS (r = 0.82; p < 0.0001) and between log(HRPFS) and log(HROS) (r = 0.80; p < 0.0001). Linear regression models produced R2 values of 0.67 and 0.63 when regressing HROS on HRPFS, and log(HROS) on log(HRPFS), respectively. Sensitivity analyses supported the HR findings. Conclusion: This analysis provides evidence for a positive association between treatment effects on PFS and OS. Studies involving patient level data are necessary to confirm whether PFS is a valid surrogate for OS in MM.

Severe infusion reactions (SIRs) at rates of 5% or less are known side effects of biological agents, including mAbs such as cetuximab. There are currently no prospectively validated risk factors to aid physicians in identifying patients who may be at risk of experiencing an SIR following administration of any of these drugs. A retrospective analysis of 545 banked serum or plasma samples from cancer patients participating in clinical trials of cetuximab was designed to evaluate whether the presence of pretreatment IgE antibodies against cetuximab, as determined by a commercially available assay system, is associated with SIRs during the initial cetuximab infusion. Patients with a positive test indicating the presence of pretreatment antibodies had a higher risk of experiencing an SIR; however, at the prespecified cutoff utilized in this analysis, the test has a relatively low-positive predictive value (0.577 [0.369–0.766]) and a negative predictive value of 0.961 (0.912–0.987) in an unselected patient population. Data collected in this large retrospective validation study support prior observations of an association between the presence of pretreatment IgE antibodies cross-reactive with cetuximab and SIRs. Further analysis of the test's ability to predict patients at risk of an SIR would be required before this assay could be used reliably in this patient population.

Purpose Retrospective studies have reported that tumor expression of the beta-3 tubulin (β3T) isoform is an unfavorable prognostic factor in non–small-cell lung cancer (NSCLC) treated with tubulin-inhibiting chemotherapy. Ixabepilone is a tubulin-inhibiting agent with low susceptibility to multiple resistance mechanisms including β3T isoform expression in several tumor models. This randomized phase II study evaluated ixabepilone-based chemotherapy in stage IIIb/IV NSCLC, compared with paclitaxel-based chemotherapy. Tumor specimens were prospectively evaluated for β3T expression. Patients and Methods Patients were stratified by β3T status (positive v negative) and randomly assigned at a ratio of 1:1 to receive ixabepilone (32 mg/m2) and carboplatin (area under concentration-time curve [AUC], 6) or paclitaxel (200 mg/m2) and carboplatin (AUC, 6) for up to six cycles. The primary end point was progression-free survival (PFS) in the β3T-positive subgroup. Results Ninety-five patients (β3T positive, 52; β3T negative, 43) received ixabepilone plus carboplatin; 96 patients (β3T positive, 49; β3T negative, 47) received paclitaxel plus carboplatin. No significant differences in median PFS were observed between arms for either subgroup (β3T positive, 4.3 months in both arms; β3T negative, 5.8 v 5.3 months). Ixabepilone did not significantly improve overall survival (OS) for the β3T-positive subset or the overall population. Adverse events were similar between the two arms and comparable with those in previous studies. Conclusion There was no predictive value of β3T in differentiating clinical activity of ixabepilone- or paclitaxel-containing regimens. Ixabepilone did not improve PFS or OS in patients with β3T-positive tumors. β3T-positive patients had worse PFS relative to β3T-negative patients, regardless of treatment; hence, β3T expression seems to be a negative prognostic factor, but not a predictive factor, in advanced NSCLC treated with either ixabepilone or paclitaxel platinum-based doublets.

Data on chemotherapy regimens in elderly patients with metastatic breast cancer (MBC) are limited. The aim of this retrospective pooled analysis was to determine efficacy and safety of ixabepilone plus capecitabine versus capecitabine alone in patients with MBC aged ≥ 65 years.A total of 1973 patients with MBC previously treated with or resistant to anthracyclines and taxanes were randomized in two open-label, multinational, phase 3 studies (study 046 and study 048). Patients received ixabepilone (40 mg/m(2) as a 3-hour intravenous infusion every 3 weeks) plus oral capecitabine (1000 mg/m(2) administered twice each day), or capecitabine alone (1250 mg/m(2) twice each day).In total, 251 randomized patients were aged ≥ 65 years (ixabepilone plus capecitabine, n=116; capecitabine monotherapy, n=135). Efficacy results were consistent in patients aged65 and ≥ 65 years with respect to the observed improvement in progression-free survival and objective response rate with ixabepilone plus capecitabine compared with capecitabine alone. No significant differences in overall survival between arms were observed for either subgroup. In the ixabepilone plus capecitabine arm, grade 3/4 hematologic adverse events (AEs) were similar in both subgroups except leukopenia and febrile neutropenia, which had a higher incidence in patients aged ≥ 65 years. The majority of grade 3/4 nonhematologic AEs were similar in the two subgroups, including fatigue, peripheral sensory neuropathy, and hand-foot syndrome.The combination of ixabepilone plus capecitabine maintains its efficacy in elderly patients with anthracycline and taxane pretreated MBC, with a similar safety profile to patients aged65 years.

Combination therapy with ixabepilone and capecitabine (cape) is approved for use in patients with locally advanced/metastatic breast cancer that is resistant to treatment with anthracyclines or taxanes. The current study evaluated the trade-off between quality and quantity of life using quality-adjusted time without symptoms or toxicity (Q-TWiST) outcomes.Within the trial, 752 women were randomly assigned to receive either the combination of ixabepilone and cape (once every 21 days) or cape alone (on days 1-14). The area under the survival curve was partitioned into 3 health states: toxicity (TOX), time without symptoms of disease progression or toxicity, and recurrence (relapse [REL]). The mean time in each health state was weighted by a range of utilities and summed to estimate quality-adjusted survival (QAS). Patient-reported outcomes were also evaluated using the Functional Assessment of Cancer Therapy (FACT)-Breast Symptom Index (FBSI).A statistically significant difference between groups with regard to change from baseline FBSI scores favoring the cape group was observed (P = .0002), but no differences were observed after adjusting for deaths in the analysis. All combinations of utilities for REL and TOX resulted in an observed difference in QAS favoring combination therapy. Differences were found to be statistically significant for comparisons, with higher tolerance for TOX. QAS was found to be greater for the combination therapy group (42.2 weeks vs 38.4 weeks), assuming the base case scenario of utility equal to 0.5 for both TOX and REL (P = .0227).The Q-TWiST analysis supports a positive benefit-risk ratio for the combination of ixabepilone plus cape in patients with advanced/metastatic breast cancer that is refractory to anthracyclines and taxanes versus cape alone, despite the potential for added toxicities with combination therapy.