Browsing by Author "Halabi, Susan"

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    ItemOpen Access
    Abatacept, Cenicriviroc, or Infliximab for Treatment of Adults Hospitalized With COVID-19 Pneumonia: A Randomized Clinical Trial.
    (JAMA, 2023-07) O'Halloran, Jane A; Ko, Emily R; Anstrom, Kevin J; Kedar, Eyal; McCarthy, Matthew W; Panettieri, Reynold A; Maillo, Martin; Nunez, Patricia Segura; Lachiewicz, Anne M; Gonzalez, Cynthia; Smith, P Brian; de Tai, Sabina Mendivil-Tuchia; Khan, Akram; Lora, Alfredo J Mena; Salathe, Matthias; Capo, Gerardo; Gonzalez, Daniel Rodríguez; Patterson, Thomas F; Palma, Christopher; Ariza, Horacio; Lima, Maria Patelli; Blamoun, John; Nannini, Esteban C; Sprinz, Eduardo; Mykietiuk, Analia; Alicic, Radica; Rauseo, Adriana M; Wolfe, Cameron R; Witting, Britta; Wang, Jennifer P; Parra-Rodriguez, Luis; Der, Tatyana; Willsey, Kate; Wen, Jun; Silverstein, Adam; O'Brien, Sean M; Al-Khalidi, Hussein R; Maldonado, Michael A; Melsheimer, Richard; Ferguson, William G; McNulty, Steven E; Zakroysky, Pearl; Halabi, Susan; Benjamin, Daniel K; Butler, Sandra; Atkinson, Jane C; Adam, Stacey J; Chang, Soju; LaVange, Lisa; Proschan, Michael; Bozzette, Samuel A; Powderly, William G; ACTIV-1 IM Study Group Members

    Importance

    Immune dysregulation contributes to poorer outcomes in COVID-19.

    Objective

    To investigate whether abatacept, cenicriviroc, or infliximab provides benefit when added to standard care for COVID-19 pneumonia.

    Design, setting, and participants

    Randomized, double-masked, placebo-controlled clinical trial using a master protocol to investigate immunomodulators added to standard care for treatment of participants hospitalized with COVID-19 pneumonia. The results of 3 substudies are reported from 95 hospitals at 85 clinical research sites in the US and Latin America. Hospitalized patients 18 years or older with confirmed SARS-CoV-2 infection within 14 days and evidence of pulmonary involvement underwent randomization between October 2020 and December 2021.

    Interventions

    Single infusion of abatacept (10 mg/kg; maximum dose, 1000 mg) or infliximab (5 mg/kg) or a 28-day oral course of cenicriviroc (300-mg loading dose followed by 150 mg twice per day).

    Main outcomes and measures

    The primary outcome was time to recovery by day 28 evaluated using an 8-point ordinal scale (higher scores indicate better health). Recovery was defined as the first day the participant scored at least 6 on the ordinal scale.

    Results

    Of the 1971 participants randomized across the 3 substudies, the mean (SD) age was 54.8 (14.6) years and 1218 (61.8%) were men. The primary end point of time to recovery from COVID-19 pneumonia was not significantly different for abatacept (recovery rate ratio [RRR], 1.12 [95% CI, 0.98-1.28]; P = .09), cenicriviroc (RRR, 1.01 [95% CI, 0.86-1.18]; P = .94), or infliximab (RRR, 1.12 [95% CI, 0.99-1.28]; P = .08) compared with placebo. All-cause 28-day mortality was 11.0% for abatacept vs 15.1% for placebo (odds ratio [OR], 0.62 [95% CI, 0.41-0.94]), 13.8% for cenicriviroc vs 11.9% for placebo (OR, 1.18 [95% CI 0.72-1.94]), and 10.1% for infliximab vs 14.5% for placebo (OR, 0.59 [95% CI, 0.39-0.90]). Safety outcomes were comparable between active treatment and placebo, including secondary infections, in all 3 substudies.

    Conclusions and relevance

    Time to recovery from COVID-19 pneumonia among hospitalized participants was not significantly different for abatacept, cenicriviroc, or infliximab vs placebo.

    Trial registration

    ClinicalTrials.gov Identifier: NCT04593940.
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    Comparison of regression imputation methods of baseline covariates that predict survival outcomes.
    (Journal of clinical and translational science, 2020-09) Solomon, Nicole; Lokhnygina, Yuliya; Halabi, Susan

    Introduction

    Missing data are inevitable in medical research and appropriate handling of missing data is critical for statistical estimation and making inferences. Imputation is often employed in order to maximize the amount of data available for statistical analysis and is preferred over the typically biased output of complete case analysis. This article examines several types of regression imputation of missing covariates in the prediction of time-to-event outcomes subject to right censoring.

    Methods

    We evaluated the performance of five regression methods in the imputation of missing covariates for the proportional hazards model via summary statistics, including proportional bias and proportional mean squared error. The primary objective was to determine which among the parametric generalized linear models (GLMs) and least absolute shrinkage and selection operator (LASSO), and nonparametric multivariate adaptive regression splines (MARS), support vector machine (SVM), and random forest (RF), provides the "best" imputation model for baseline missing covariates in predicting a survival outcome.

    Results

    LASSO on an average observed the smallest bias, mean square error, mean square prediction error, and median absolute deviation (MAD) of the final analysis model's parameters among all five methods considered. SVM performed the second best while GLM and MARS exhibited the lowest relative performances.

    Conclusion

    LASSO and SVM outperform GLM, MARS, and RF in the context of regression imputation for prediction of a time-to-event outcome.
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    Developing and Validating Risk Assessment Models of Clinical Outcomes in Modern Oncology.
    (JCO precision oncology, 2019-01) Halabi, Susan; Li, Cai; Luo, Sheng
    The identification of prognostic factors and building of risk assessment prognostic models will continue to play a major role in 21st century medicine in patient management and decision making. Investigators are often interested in examining the relationship between host, tumor-related, and environmental variables in predicting clinical outcomes. We make a distinction between static and dynamic prediction models. In static prediction modelling, typically variables collected at baseline are utilized in building models. On the other hand, dynamic predictive models leverage the longitudinal data of covariates collected during treatment or follow-up, and hence provide accurate predictions of patients prognoses. To date, most risk assessment models in oncology have been based on static models. In this article, we cover topics that are related to the analysis of prognostic factors, centering on factors that are both relevant at the time of diagnosis or initial treatment and during treatment. We describe the types of risk prediction and then provide a brief description of the penalized regression methods. We then review the state-of-the art methods for dynamic prediction and compare the strengths and the limitations of these methods. While static models will continue to play an important role in oncology, developing and validating dynamic models of clinical outcomes need to take a higher priority. It is apparent that a framework for developing and validating dynamic tools in oncology is still needed. One of the limitations in oncology that modelers may be constrained by the lack of access to the longitudinal biomarker data. It is highly recommended that the next generation of risk assessments consider the longitudinal biomarker data and outcomes so that prediction can be continually updated.
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    ItemOpen Access
    High Dimensional Variable Selection with Error Control.
    (Biomed Res Int, 2016) Kim, Sangjin; Halabi, Susan
    Background. The iterative sure independence screening (ISIS) is a popular method in selecting important variables while maintaining most of the informative variables relevant to the outcome in high throughput data. However, it not only is computationally intensive but also may cause high false discovery rate (FDR). We propose to use the FDR as a screening method to reduce the high dimension to a lower dimension as well as controlling the FDR with three popular variable selection methods: LASSO, SCAD, and MCP. Method. The three methods with the proposed screenings were applied to prostate cancer data with presence of metastasis as the outcome. Results. Simulations showed that the three variable selection methods with the proposed screenings controlled the predefined FDR and produced high area under the receiver operating characteristic curve (AUROC) scores. In applying these methods to the prostate cancer example, LASSO and MCP selected 12 and 8 genes and produced AUROC scores of 0.746 and 0.764, respectively. Conclusions. We demonstrated that the variable selection methods with the sequential use of FDR and ISIS not only controlled the predefined FDR in the final models but also had relatively high AUROC scores.
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    Meta-Analysis Evaluating the Impact of Site of Metastasis on Overall Survival in Men With Castration-Resistant Prostate Cancer.
    (Journal of clinical oncology : official journal of the American Society of Clinical Oncology, 2016-05) Halabi, Susan; Kelly, William Kevin; Ma, Hua; Zhou, Haojin; Solomon, Nicole C; Fizazi, Karim; Tangen, Catherine M; Rosenthal, Mark; Petrylak, Daniel P; Hussain, Maha; Vogelzang, Nicholas J; Thompson, Ian M; Chi, Kim N; de Bono, Johann; Armstrong, Andrew J; Eisenberger, Mario A; Fandi, Abderrahim; Li, Shaoyi; Araujo, John C; Logothetis, Christopher J; Quinn, David I; Morris, Michael J; Higano, Celestia S; Tannock, Ian F; Small, Eric J

    Purpose

    Reports have suggested that metastatic site is an important predictor of overall survival (OS) in men with metastatic castration-resistant prostate cancer (mCRPC), but these were based on a limited number of patients. We investigate the impact of site of metastases on OS of a substantial sample of men with mCRPC who received docetaxel chemotherapy in nine phase III trials.

    Patients and methods

    Individual patient data from 8,820 men with mCRPC enrolled onto nine phase III trials were combined. Site of metastases was categorized as lymph node (LN) only, bone with or without LN (with no visceral metastases), any lung metastases (but no liver), and any liver metastases.

    Results

    Most patients had bone with or without LN metastases (72.8%), followed by visceral disease (20.8%) and LN-only disease (6.4%). Men with liver metastases had the worst median OS (13.5 months). Although men with lung metastases had better median OS (19.4 months) compared with men with liver metastases, they had significantly worse median survival duration than men with nonvisceral bone metastases (21.3 months). Men with LN-only disease had a median OS of 31.6 months. The pooled hazard ratios for death in men with lung metastases compared with men with bone with or without LN metastases and in men with any liver metastases compared with men with lung metastases were 1.14 (95% CI, 1.04 to 1.25; P = .007) and 1.52 (95% CI, 1.35 to 1.73; P < .0001), respectively.

    Conclusion

    Specific sites of metastases in men with mCRPC are associated with differential OS, with successive increased lethality for lung and liver metastases compared with bone and nonvisceral involvement. These data may help in treatment decisions, the design of future clinical trials, and understanding the variation in biology of different sites of metastases in men with mCRPC.
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    Prostate-specific antigen changes as surrogate for overall survival in men with metastatic castration-resistant prostate cancer treated with second-line chemotherapy.
    (Journal of clinical oncology : official journal of the American Society of Clinical Oncology, 2013-11) Halabi, Susan; Armstrong, Andrew J; Sartor, Oliver; de Bono, Johann; Kaplan, Ellen; Lin, Chen-Yen; Solomon, Nicole C; Small, Eric J

    Purpose

    Prostate-specific antigen (PSA) kinetics, and more specifically a ≥ 30% decline in PSA within 3 months after initiation of first-line chemotherapy with docetaxel, are associated with improvement in overall survival (OS) in men with metastatic castration-resistant prostate cancer (mCRPC). The objective of this analysis was to evaluate post-treatment PSA kinetics as surrogates for OS in patients receiving second-line chemotherapy.

    Patients and methods

    Data from a phase III trial of patients with mCRPC randomly assigned to cabazitaxel plus prednisone (C + P) or mitoxantrone plus prednisone were used. PSA decline (≥ 30% and ≥ 50%), velocity, and rise within the first 3 months of treatment were evaluated as surrogates for OS. The Prentice criteria, proportion of treatment explained (PTE), and meta-analytic approaches were used as measures of surrogacy.

    Results

    The observed hazard ratio (HR) for death for patients treated with C + P was 0.66 (95% CI, 0.55 to 0.79; P < .001). Furthermore, a ≥ 30% decline in PSA was a statistically significant predictor of OS (HR for death, 0.52; 95% CI, 0.43 to 0.64; P < .001). Adjusting for treatment effect, the HR for a ≥ 30% PSA decline was 0.50 (95% CI, 0.40 to 0.62; P < .001), but treatment remained statistically significant, thus failing the third Prentice criterion. The PTE for a ≥ 30% decline in PSA was 0.34 (95% CI, 0.11 to 0.56), indicating a lack of surrogacy for OS. The values of R(2) were < 1, suggesting that PSA decline was not surrogate for OS.

    Conclusion

    Surrogacy for any PSA-based end point could not be demonstrated in this analysis. Thus, the benefits of cabazitaxel in mediating a survival benefit are not fully captured by early PSA changes.
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    Residential metal contamination and potential health risks of exposure in adobe brick houses in Potosí, Bolivia.
    (The Science of the total environment, 2016-08) McEwen, Abigail R; Hsu-Kim, Heileen; Robins, Nicholas A; Hagan, Nicole A; Halabi, Susan; Barras, Olivo; Richter, Daniel deB; Vandenberg, John J
    Potosí, Bolivia, is the site of centuries of historic and present-day mining of the Cerro Rico, a mountain known for its rich polymetallic deposits, and was the site of large-scale Colonial era silver refining operations. In this study, the concentrations of several metal and metalloid elements were quantified in adobe brick, dirt floor, and surface dust samples from 49 houses in Potosí. Median concentrations of total mercury (Hg), lead (Pb), and arsenic (As) were significantly greater than concentrations measured in Sucre, Bolivia, a non-mining town, and exceeded US-based soil screening levels. Adobe brick samples were further analyzed for bioaccessible concentrations of trace elements using a simulated gastric fluid (GF) extraction. Median GF extractable concentrations of Hg, As, and Pb were 0.085, 13.9, and 32.2% of the total element concentration, respectively. Total and GF extractable concentrations of Hg, As, and Pb were used to estimate exposure and potential health risks to children following incidental ingestion of adobe brick particles. Risks were assessed using a range of potential ingestion rates (50-1000mg/day). Overall, the results of the risk assessment show that the majority of households sampled contained concentrations of bioaccessible Pb and As, but not Hg, that represent a potential health risk. Even at the lowest ingestion rate considered, the majority of households exceeded the risk threshold for Pb, indicating that the concentrations of this metal are of particular concern. To our knowledge, this is the first study to quantify key trace elements in building materials in adobe brick houses and the results indicate that these houses are a potential source of exposure to metals and metalloids in South American mining communities. Additional studies are needed to fully characterize personal exposure and to understand potential adverse health outcomes within the community.