Browsing by Author "Evans, Scott"

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    ItemOpen Access
    Clinical outcomes and bacterial characteristics of carbapenem-resistant Klebsiella pneumoniae complex among patients from different global regions (CRACKLE-2): a prospective, multicentre, cohort study.
    (The Lancet. Infectious diseases, 2021-11-09) Wang, Minggui; Earley, Michelle; Chen, Liang; Hanson, Blake M; Yu, Yunsong; Liu, Zhengyin; Salcedo, Soraya; Cober, Eric; Li, Lanjuan; Kanj, Souha S; Gao, Hainv; Munita, Jose M; Ordoñez, Karen; Weston, Greg; Satlin, Michael J; Valderrama-Beltrán, Sandra L; Marimuthu, Kalisvar; Stryjewski, Martin E; Komarow, Lauren; Luterbach, Courtney; Marshall, Steve H; Rudin, Susan D; Manca, Claudia; Paterson, David L; Reyes, Jinnethe; Villegas, Maria V; Evans, Scott; Hill, Carol; Arias, Rebekka; Baum, Keri; Fries, Bettina C; Doi, Yohei; Patel, Robin; Kreiswirth, Barry N; Bonomo, Robert A; Chambers, Henry F; Fowler, Vance G; Arias, Cesar A; van Duin, David; Multi-Drug Resistant Organism Network Investigators

    Background

    Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a global threat. We therefore analysed the bacterial characteristics of CRKP infections and the clinical outcomes of patients with CRKP infections across different countries.

    Methods

    In this prospective, multicentre, cohort study (CRACKLE-2), hospitalised patients with cultures positive for CRKP were recruited from 71 hospitals in Argentina, Australia, Chile, China, Colombia, Lebanon, Singapore, and the USA. The first culture positive for CRKP was included for each unique patient. Clinical data on post-hospitalisation death and readmission were collected from health records, and whole genome sequencing was done on all isolates. The primary outcome was a desirability of outcome ranking at 30 days after the index culture, and, along with bacterial characteristics and 30-day all-cause mortality (a key secondary outcome), was compared between patients from China, South America, and the USA. The desirability of outcome ranking was adjusted for location before admission, Charlson comorbidity index, age at culture, Pitt bacteremia score, and anatomical culture source through inverse probability weighting; mortality was adjusted for the same confounders, plus region where relevant, through multivariable logistic regression. This study is registered at ClinicalTrials.gov, NCT03646227, and is complete.

    Findings

    Between June 13, 2017, and Nov 30, 2018, 991 patients were enrolled, of whom 502 (51%) met the criteria for CRKP infection and 489 (49%) had positive cultures that were considered colonisation. We observed little intra-country genetic variation in CRKP. Infected patients from the USA were more acutely ill than were patients from China or South America (median Pitt bacteremia score 3 [IQR 2-6] vs 2 [0-4] vs 2 [0-4]) and had more comorbidities (median Charlson comorbidity index 3 [IQR 2-5] vs 1 [0-3] vs 1 [0-2]). Adjusted desirability of outcome ranking outcomes were similar in infected patients from China (n=246), South America (n=109), and the USA (n=130); the estimates were 53% (95% CI 42-65) for China versus South America, 50% (41-61) for the USA versus China, and 53% (41-66) for the USA versus South America. In patients with CRKP infections, unadjusted 30-day mortality was lower in China (12%, 95% CI 8-16; 29 of 246) than in the USA (23%, 16-30; 30 of 130) and South America (28%, 20-37; 31 of 109). Adjusted 30-day all-cause mortality was higher in South America than in China (adjusted odds ratio [aOR] 4·82, 95% CI 2·22-10·50) and the USA (aOR 3·34, 1·50-7·47), with the mortality difference between the USA and China no longer being significant (aOR 1·44, 0·70-2·96).

    Interpretation

    Global CRKP epidemics have important regional differences in patients' baseline characteristics and clinical outcomes, and in bacterial characteristics. Research findings from one region might not be generalisable to other regions.

    Funding

    The National Institutes of Health.
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    Clinically Adjudicated Reference Standards for Evaluation of Infectious Diseases Diagnostics.
    (Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2023-03) Patel, Robin; Tsalik, Ephraim L; Evans, Scott; Fowler, Vance G; Doernberg, Sarah B; Antibacterial Resistance Leadership Group
    Lack of a gold standard can present a challenge for evaluation of diagnostic test accuracy of some infectious diseases tests, particularly when the test's accuracy potentially exceeds that of its predecessors. This approach may measure agreement with an imperfect reference, rather than correctness, because the right answer is unknown. Solutions consist of multitest comparators, including those that involve a test under evaluation if multiple new tests are being evaluated together, using latent class modeling, and clinically adjudicated reference standards. Clinically adjudicated reference standards may be considered as comparator methods when no predefined test or composite of tests is sufficiently accurate; they emulate clinical practice in that multiple data pieces are clinically assessed together.
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    Dalbavancin as an option for treatment of S. aureus bacteremia (DOTS): study protocol for a phase 2b, multicenter, randomized, open-label clinical trial.
    (Trials, 2022-05) Turner, Nicholas A; Zaharoff, Smitha; King, Heather; Evans, Scott; Hamasaki, Toshimitsu; Lodise, Thomas; Ghazaryan, Varduhi; Beresnev, Tatiana; Riccobene, Todd; Patel, Rinal; Doernberg, Sarah B; Rappo, Urania; Fowler, Vance G; Holland, Thomas L; Antibacterial Resistance Leadership Group (ARLG)

    Background

    Staphylococcus aureus bacteremia is a life-threatening infection and leading cause of infective endocarditis, with mortality rates of 15-50%. Treatment typically requires prolonged administration of parenteral therapy, itself associated with high costs and potential catheter-associated complications. Dalbavancin is a lipoglycopeptide with potent activity against Staphylococcus and a long half-life, making it an appealing potential therapy for S. aureus bacteremia without the need for durable central venous access.

    Methods

    DOTS is a phase 2b, multicenter, randomized, assessor-blinded, superiority, active-controlled, parallel-group trial. The trial will enroll 200 adults diagnosed with complicated S. aureus bacteremia, including definite or possible right-sided infective endocarditis, who have been treated with effective antibiotic therapy for at least 72 h (maximum 10 days) and with subsequent clearance of bacteremia prior to randomization to study treatment. Subjects will be randomized 1:1 to complete their antibiotic treatment course with either two doses of dalbavancin on days 1 and 8, or with a total of 4-8 weeks of standard intravenous antibiotic therapy. The primary objective is to compare the Desirability of Outcome Ranking (DOOR) at day 70 for patients randomized to dalbavancin versus standard of care. Key secondary endpoints include quality of life outcomes and pharmacokinetic analyses of dalbavancin.

    Discussion

    The DOTS trial will establish whether dalbavancin is superior to standard parenteral antibiotic therapy for the completion of treatment of complicated S. aureus bacteremia.

    Trial registration

    US National Institutes of Health ClinicalTrials.gov NCT04775953 . Registered on 1 March 2021.
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    Exploration of a Potential Desirability of Outcome Ranking Endpoint for Complicated Intra-Abdominal Infections Using 9 Registrational Trials for Antibacterial Drugs.
    (Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2023-08) Kinamon, Tori; Gopinath, Ramya; Waack, Ursula; Needles, Mark; Rubin, Daniel; Collyar, Deborah; Doernberg, Sarah B; Evans, Scott; Hamasaki, Toshimitsu; Holland, Thomas L; Howard-Anderson, Jessica; Chambers, Henry; Fowler, Vance G; Nambiar, Sumati; Kim, Peter; Boucher, Helen W

    Background

    Desirability of outcome ranking (DOOR) is a novel approach to clinical trial design that incorporates safety and efficacy assessments into an ordinal ranking system to evaluate overall outcomes of clinical trial participants. Here, we derived and applied a disease-specific DOOR endpoint to registrational trials for complicated intra-abdominal infection (cIAI).

    Methods

    Initially, we applied an a priori DOOR prototype to electronic patient-level data from 9 phase 3 noninferiority trials for cIAI submitted to the US Food and Drug Administration between 2005 and 2019. We derived a cIAI-specific DOOR endpoint based on clinically meaningful events that trial participants experienced. Next, we applied the cIAI-specific DOOR endpoint to the same datasets and, for each trial, estimated the probability that a participant assigned to the study treatment would have a more desirable DOOR or component outcome than if assigned to the comparator.

    Results

    Three key findings informed the cIAI-specific DOOR endpoint: (1) a significant proportion of participants underwent additional surgical procedures related to their baseline infection; (2) infectious complications of cIAI were diverse; and (3) participants with worse outcomes experienced more infectious complications, more serious adverse events, and underwent more procedures. DOOR distributions between treatment arms were similar in all trials. DOOR probability estimates ranged from 47.4% to 50.3% and were not significantly different. Component analyses depicted risk-benefit assessments of study treatment versus comparator.

    Conclusions

    We designed and evaluated a potential DOOR endpoint for cIAI trials to further characterize overall clinical experiences of participants. Similar data-driven approaches can be utilized to create other infectious disease-specific DOOR endpoints.
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    MASTERMIND: Bringing Microbial Diagnostics to the Clinic.
    (Clin Infect Dis, 2017-02-01) Patel, Robin; Tsalik, Ephraim L; Petzold, Elizabeth; Fowler, Vance G; Klausner, Jeffrey D; Evans, Scott; Antibacterial Resistance Leadership Group (ARLG)
    New diagnostics are urgently needed to address emerging antimicrobial resistance. The Antibacterial Resistance Leadership Group proposes a strategy called MASTERMIND (Master Protocol for Evaluating Multiple Infection Diagnostics) for advancement of infectious diseases diagnostics. The goal of this strategy is to generate the data necessary to support US Food and Drug Administration clearance of new diagnostic tests by promoting research that might not have otherwise been feasible with conventional trial designs. MASTERMIND uses a single subject's sample(s) to evaluate multiple diagnostic tests at the same time, providing efficiencies of specimen collection and characterization. MASTERMIND also offers central trial organization, standardization of methods and definitions, and common comparators.
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    Short- vs Standard-Course Outpatient Antibiotic Therapy for Community-Acquired Pneumonia in Children: The SCOUT-CAP Randomized Clinical Trial.
    (JAMA pediatrics, 2022-01-18) Williams, Derek J; Creech, C Buddy; Walter, Emmanuel B; Martin, Judith M; Gerber, Jeffrey S; Newland, Jason G; Howard, Lee; Hofto, Meghan E; Staat, Mary A; Oler, Randolph E; Tuyishimire, Bonifride; Conrad, Thomas M; Lee, Marina S; Ghazaryan, Varduhi; Pettigrew, Melinda M; Fowler, Vance G; Chambers, Henry F; Zaoutis, Theoklis E; Evans, Scott; Huskins, W Charles; The DMID 14-0079 Study Team

    Importance

    Childhood community-acquired pneumonia (CAP) is usually treated with 10 days of antibiotics. Shorter courses may be effective with fewer adverse effects and decreased potential for antibiotic resistance.

    Objective

    To compare a short (5-day) vs standard (10-day) antibiotic treatment strategy for CAP in young children.

    Design, setting, and participants

    Randomized double-blind placebo-controlled clinical trial in outpatient clinic, urgent care, or emergency settings in 8 US cities. A total of 380 healthy children aged 6 to 71 months with nonsevere CAP demonstrating early clinical improvement were enrolled from December 2, 2016, to December 16, 2019. Data were analyzed from January to September 2020.

    Intervention

    On day 6 of their originally prescribed therapy, participants were randomized 1:1 to receive 5 days of matching placebo or 5 additional days of the same antibiotic.

    Main outcomes and measures

    The primary end point was the end-of-treatment response adjusted for duration of antibiotic risk (RADAR), a composite end point that ranks each child's clinical response, resolution of symptoms, and antibiotic-associated adverse effects in an ordinal desirability of outcome ranking (DOOR). Within each DOOR rank, participants were further ranked by the number of antibiotic days, assuming that shorter antibiotic durations were more desirable. Using RADAR, the probability of a more desirable outcome was estimated for the short- vs standard-course strategy. In a subset of children, throat swabs were collected between study days 19 and 25 to quantify antibiotic resistance genes in oropharyngeal flora.

    Results

    A total of 380 children (189 randomized to short course and 191 randomized to standard course) made up the study population. The mean (SD) age was 35.7 (17.2) months, and 194 participants (51%) were male. Of the included children, 8 were Asian, 99 were Black or African American, 234 were White, 32 were multiracial, and 7 were of unknown or unreported race; 33 were Hispanic or Latino, 344 were not Hispanic or Latino, and 3 were of unknown or unreported ethnicity. There were no differences between strategies in the DOOR or its individual components. Fewer than 10% of children in either strategy had an inadequate clinical response. The short-course strategy had a 69% (95% CI, 63-75) probability of a more desirable RADAR outcome compared with the standard-course strategy. A total of 171 children were included in the resistome analysis. The median (range) number of antibiotic resistance genes per prokaryotic cell (RGPC) was significantly lower in the short-course strategy compared with the standard-course strategy for total RGPC (1.17 [0.35-2.43] vs 1.33 [0.46-11.08]; P = .01) and β-lactamase RGPC (0.55 [0.18-1.24] vs 0.60 [0.21-2.45]; P = .03).

    Conclusions and relevance

    In this study, among children responding to initial treatment for outpatient CAP, a 5-day antibiotic strategy was superior to a 10-day strategy. The shortened approach resulted in similar clinical response and antibiotic-associated adverse effects, while reducing antibiotic exposure and resistance.

    Trial registration

    ClinicalTrials.gov Identifier: NCT02891915.