1
|
Beyersmann J, Friede T, Schmoor C. Design aspects of COVID-19 treatment trials: Improving probability and time of favorable events. Biom J 2022; 64:440-460. [PMID: 34677829 PMCID: PMC8653377 DOI: 10.1002/bimj.202000359] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 08/13/2021] [Accepted: 09/04/2021] [Indexed: 12/24/2022]
Abstract
As a reaction to the pandemic of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a multitude of clinical trials for the treatment of SARS-CoV-2 or the resulting corona disease 2019 (COVID-19) are globally at various stages from planning to completion. Although some attempts were made to standardize study designs, this was hindered by the ferocity of the pandemic and the need to set up clinical trials quickly. We take the view that a successful treatment of COVID-19 patients (i) increases the probability of a recovery or improvement within a certain time interval, say 28 days; (ii) aims to expedite favorable events within this time frame; and (iii) does not increase mortality over this time period. On this background, we discuss the choice of endpoint and its analysis. Furthermore, we consider consequences of this choice for other design aspects including sample size and power and provide some guidance on the application of adaptive designs in this particular context.
Collapse
Affiliation(s)
| | - Tim Friede
- Institut für Medizinische StatistikUniversitätsmedizin GöttingenGöttingenGermany
- Deutsches Zentrum für Herz‐Kreislaufforschung (DZHK)Standort GöttingenGöttingenGermany
| | - Claudia Schmoor
- Zentrum Klinische Studien, Universitätsklinikum Freiburg, Medizinische FakultätAlbert‐Ludwigs Universität FreiburgFreiburg im BreisgauGermany
| |
Collapse
|
2
|
Bluhmki T, Schmoor C, Finke J, Schumacher M, Socié G, Beyersmann J. Relapse- and Immunosuppression-Free Survival after Hematopoietic Stem Cell Transplantation: How Can We Assess Treatment Success for Complex Time-to-Event Endpoints? Biol Blood Marrow Transplant 2020; 26:992-997. [PMID: 31927103 DOI: 10.1016/j.bbmt.2020.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 12/02/2019] [Accepted: 01/03/2020] [Indexed: 12/26/2022]
Abstract
In most clinical oncology trials, time-to-first-event analyses are used for efficacy assessment, which often do not capture the entire disease process. Instead, the focus may be on more complex time-to-event endpoints, such as the course of disease after the first event or endpoints occurring after randomization. We propose "relapse- and immunosuppression-free survival" (RIFS) as an innovative and clinically relevant outcome measure for assessing treatment success after hematopoietic stem cell transplant (SCT). To capture the time-dynamic relationship of multiple episodes of immunosuppressive therapy during follow-up, relapse, and nonrelapse mortality, a multistate model was developed. The statistical complexity is that the probability of RIFS is nonmonotonic over time; thus, standard time-to-first-event methodology is inappropriate for formal treatment comparisons. Instead, a generalization of the Kaplan-Meier method was used for probability estimation, and simulation-based resampling was suggested as a strategy for statistical inference. We reanalyzed data from a recently published phase III trial in 201 leukemia patients after SCT. The study evaluated long-term treatment success of standard graft-versus-host disease prophylaxis plus a pretransplant antihuman T-lymphocyte immunoglobulin compared with standard prophylaxis alone. Results suggested that treatment increased the long-term probability of RIFS by approximately 30% during the entire follow-up period, which complements the original findings. This article highlights the importance of complex endpoints in oncology, which provide deeper insight into the treatment and disease process over time. Multistate models combined with resampling are highlighted as a promising tool to evaluate treatment success beyond standard endpoints. An example code is provided in the Supplementary Materials.
Collapse
Affiliation(s)
| | - Claudia Schmoor
- Clinical Trials Unit, Faculty of Medicine and Medical Center, University of Freiburg, Freiburg, Germany
| | - Jürgen Finke
- Department of Hematology, Oncology, and Stem-Cell Transplantation, Faculty of Medicine and Medical Center, University of Freiburg, Freiburg, Germany
| | - Martin Schumacher
- Institute for Medical Biometry and Medical Statistics, Faculty of Medicine and Medical Center, University of Freiburg, Freiburg, Germany
| | - Gérard Socié
- Université de Paris, INSERM U976 and Hématologie-Transplantation, Hôpital St. Louis, Paris, France
| | | |
Collapse
|
3
|
de Kraker MEA, Sommer H, de Velde F, Gravestock I, Weiss E, McAleenan A, Nikolakopoulos S, Amit O, Ashton T, Beyersmann J, Held L, Lovering AM, MacGowan AP, Mouton JW, Timsit JF, Wilson D, Wolkewitz M, Bettiol E, Dane A, Harbarth S. Optimizing the Design and Analysis of Clinical Trials for Antibacterials Against Multidrug-resistant Organisms: A White Paper From COMBACTE's STAT-Net. Clin Infect Dis 2019; 67:1922-1931. [PMID: 30107400 PMCID: PMC6260160 DOI: 10.1093/cid/ciy516] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 06/15/2018] [Indexed: 01/08/2023] Open
Abstract
Innovations are urgently required for clinical development of antibacterials against multidrug-resistant organisms. Therefore, a European, public-private working group (STAT-Net; part of Combatting Bacterial Resistance in Europe [COMBACTE]), has reviewed and tested several innovative trials designs and analytical methods for randomized clinical trials, which has resulted in 8 recommendations. The first 3 focus on pharmacokinetic and pharmacodynamic modeling, emphasizing the pertinence of population-based pharmacokinetic models, regulatory procedures for the reassessment of old antibiotics, and rigorous quality improvement. Recommendations 4 and 5 address the need for more sensitive primary end points through the use of rank-based or time-dependent composite end points. Recommendation 6 relates to the applicability of hierarchical nested-trial designs, and the last 2 recommendations propose the incorporation of historical or concomitant trial data through Bayesian methods and/or platform trials. Although not all of these recommendations are directly applicable, they provide a solid, evidence-based approach to develop new, and established, antibacterials and address this public health challenge.
Collapse
Affiliation(s)
- Marlieke E A de Kraker
- Infection Control Program, Geneva University Hospitals and Faculty of Medicine, Switzerland
| | - Harriet Sommer
- Institute for Medical Biometry and Statistics, Faculty of Medicine and Medical Center, University of Freiburg, Germany
| | - Femke de Velde
- Department of Medical Microbiology and Infectious Diseases, Rotterdam, The Netherlands.,Department of Hospital Pharmacy, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Isaac Gravestock
- Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Switzerland
| | - Emmanuel Weiss
- Université Paris Diderot, Paris, France.,APHP Anesthesiology and Critical Care Department, Beaujon Hospital, Paris, France
| | - Alexandra McAleenan
- Department of Population Health Sciences, Bristol Medical School, University of Bristol, United Kingdom
| | - Stavros Nikolakopoulos
- Department of Biostatistics and Research Support, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands
| | - Ohad Amit
- GlaxoSmithKline, Collegeville, Pennsylvania
| | | | | | - Leonhard Held
- Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Switzerland
| | - Andrew M Lovering
- Bristol Centre for Antibiotic Research and Evaluation, Infection Sciences, North Bristol NHS Trust, Southmead Hospital, United Kingdom
| | - Alasdair P MacGowan
- Bristol Centre for Antibiotic Research and Evaluation, Infection Sciences, North Bristol NHS Trust, Southmead Hospital, United Kingdom
| | - Johan W Mouton
- Department of Medical Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Jean-François Timsit
- UMR 1137 IAME Inserm/Université Paris Diderot.,APHP Medical and Infectious Diseases ICU, Bichat Hospital, Paris, France
| | | | - Martin Wolkewitz
- Institute for Medical Biometry and Statistics, Faculty of Medicine and Medical Center, University of Freiburg, Germany
| | - Esther Bettiol
- Infection Control Program, Geneva University Hospitals and Faculty of Medicine, Switzerland
| | - Aaron Dane
- DaneStat Consulting Limited, Macclesfield, United Kingdom
| | - Stephan Harbarth
- Infection Control Program, Geneva University Hospitals and Faculty of Medicine, Switzerland
| | | |
Collapse
|
4
|
The Impact of Early Adequate Treatment on Extubation and Discharge Alive of Patients With Pseudomonas aeruginosa-Related Ventilator-Associated Pneumonia. Crit Care Med 2019; 46:1643-1648. [PMID: 29985212 DOI: 10.1097/ccm.0000000000003305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVES We aim to examine the effect of early adequate treatment in comparison with inadequate or delayed treatment on being extubated or discharged alive over time, in patients with Pseudomonas aeruginosa-related ventilator-associated pneumonia. DESIGN Retrospective analyses of a prospective observational multicenter cohort study. SETTING ICU. PATIENTS Patients of the French prospective database (OUTCOMEREA) were included if they acquired a ventilator-associated pneumonia due to P. aeruginosa between 1997 and 2014 and were mechanically ventilated for more than 48 hours. INTERVENTIONS Early adequate treatment in comparison with inadequate or delayed adequate treatment. MEASUREMENTS AND MAIN RESULTS Multistate models were applied to estimate the time-dependent probability of being extubated or discharged alive, and separate Cox regression analyses were used to assess the treatment effect on all important events that influence the outcome of interest. A propensity score-adjusted innovative regression technique was used for a combined and comprehensive patient-relevant summary effect measure. No evidence was found for a difference between adequate and inadequate or delayed treatment on being extubated or discharged alive. However, for all patients, the probability of being extubated or discharged alive remains low and does not exceed 50% even 40 days after a P. aeruginosa-related ventilator-associated pneumonia. CONCLUSIONS Early adequate treatment does not seem to be associated with an improved prognosis. Its potential benefit requires further investigation in larger observational studies.
Collapse
|
5
|
Bluhmki T, Schmoor C, Dobler D, Pauly M, Finke J, Schumacher M, Beyersmann J. A wild bootstrap approach for the Aalen-Johansen estimator. Biometrics 2018; 74:977-985. [DOI: 10.1111/biom.12861] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 12/01/2018] [Accepted: 12/01/2017] [Indexed: 11/30/2022]
Affiliation(s)
| | - Claudia Schmoor
- Clinical Trials Unit; Medical Center Freiburg; University of Freiburg; Freiburg Germany
| | - Dennis Dobler
- Institute of Statistics; Ulm University; Ulm Germany
| | - Markus Pauly
- Institute of Statistics; Ulm University; Ulm Germany
| | - Juergen Finke
- Department of Hematology; Oncology, and Stem-Cell Transplantation; Medical Center Freiburg; University of Freiburg; Freiburg Germany
| | - Martin Schumacher
- Institute for Medical Biometry and Statistics; Faculty of Medicine and Medical Center; University of Freiburg; Freiburg Germany
| | | |
Collapse
|