Surrogate Endpoint

2017 ◽  
pp. 1-5
Author(s):  
Stuart G. Baker ◽  
Barnett S. Kramer
Keyword(s):  
Surrogate Endpoint

scholarly journals Validity of Surrogate Endpoints and Their Impact on Coverage Recommendations: A Retrospective Analysis across International Health Technology Assessment Agencies

2021 ◽  
pp. 0272989X2199455
Author(s):  
Oriana Ciani ◽  
Bogdan Grigore ◽  
Hedwig Blommestein ◽  
Saskia de Groot ◽  
Meilin Möllenkamp ◽  
...  
Keyword(s):  
Health Technology Assessment ◽  
Technology Assessment ◽  
International Health ◽  
Surrogate Endpoint ◽  
Health Technology ◽  
Surrogate Endpoints ◽  
Patient Centered ◽  
Statistical Validation ◽  
Level Of Evidence ◽  
The Impact

Background Surrogate endpoints (i.e., intermediate endpoints intended to predict for patient-centered outcomes) are increasingly common. However, little is known about how surrogate evidence is handled in the context of health technology assessment (HTA). Objectives 1) To map methodologies for the validation of surrogate endpoints and 2) to determine their impact on acceptability of surrogates and coverage decisions made by HTA agencies. Methods We sought HTA reports where evaluation relied on a surrogate from 8 HTA agencies. We extracted data on the methods applied for surrogate validation. We assessed the level of agreement between agencies and fitted mixed-effects logistic regression models to test the impact of validation approaches on the agency’s acceptability of the surrogate endpoint and their coverage recommendation. Results Of the 124 included reports, 61 (49%) discussed the level of evidence to support the relationship between the surrogate and the patient-centered endpoint, 27 (22%) reported a correlation coefficient/association measure, and 40 (32%) quantified the expected effect on the patient-centered outcome. Overall, the surrogate endpoint was deemed acceptable in 49 (40%) reports ( k-coefficient 0.10, P = 0.004). Any consideration of the level of evidence was associated with accepting the surrogate endpoint as valid (odds ratio [OR], 4.60; 95% confidence interval [CI], 1.60–13.18, P = 0.005). However, we did not find strong evidence of an association between accepting the surrogate endpoint and agency coverage recommendation (OR, 0.71; 95% CI, 0.23–2.20; P = 0.55). Conclusions Handling of surrogate endpoint evidence in reports varied greatly across HTA agencies, with inconsistent consideration of the level of evidence and statistical validation. Our findings call for careful reconsideration of the issue of surrogacy and the need for harmonization of practices across international HTA agencies.

scholarly journals Correction to: 1-13C-propionate breath testing as a surrogate endpoint to assess efficacy of liver-directed therapies in methylmalonic acidemia (MMA)

2021 ◽  
Author(s):  
Irini Manoli ◽  
Alexandra R. Pass ◽  
Elizabeth A. Harrington ◽  
Jennifer L. Sloan ◽  
Jack Gagné ◽  
...  
Keyword(s):  
Surrogate Endpoint ◽  
Methylmalonic Acidemia ◽  
Breath Testing

scholarly journals Surrogate Endpoint Evaluation: Principal Stratification Criteria and the Prentice Definition

2015 ◽  
Vol 3 (2) ◽  
pp. 157-175 ◽  
Author(s):  
Peter B. Gilbert ◽  
Erin E. Gabriel ◽  
Ying Huang ◽  
Ivan S.F. Chan
Keyword(s):  
Causal Effect ◽  
Surrogate Endpoint ◽  
Effect Modification ◽  
Principal Stratification ◽  
Clinical Endpoint ◽  
Efficacy Trial ◽  
Marker Selection ◽  
Special Cases ◽  
High Utility ◽  
The Relationship

AbstractA common problem of interest within a randomized clinical trial is the evaluation of an inexpensive response endpoint as a valid surrogate endpoint for a clinical endpoint, where a chief purpose of a valid surrogate is to provide a way to make correct inferences on clinical treatment effects in future studies without needing to collect the clinical endpoint data. Within the principal stratification framework for addressing this problem based on data from a single randomized clinical efficacy trial, a variety of definitions and criteria for a good surrogate endpoint have been proposed, all based on or closely related to the “principal effects” or “causal effect predictiveness (CEP)” surface. We discuss CEP-based criteria for a useful surrogate endpoint, including (1) the meaning and relative importance of proposed criteria including average causal necessity (ACN), average causal sufficiency (ACS), and large clinical effect modification; (2) the relationship between these criteria and the Prentice definition of a valid surrogate endpoint; and (3) the relationship between these criteria and the consistency criterion (i.e. assurance against the “surrogate paradox”). This includes the result that ACN plus a strong version of ACS generally do not imply the Prentice definition nor the consistency criterion, but they do have these implications in special cases. Moreover, the converse does not hold except in a special case with a binary candidate surrogate. The results highlight that assumptions about the treatment effect on the clinical endpoint before the candidate surrogate is measured are influential for the ability to draw conclusions about the Prentice definition or consistency. In addition, we emphasize that in some scenarios that occur commonly in practice, the principal strata subpopulations for inference are identifiable from the observable data, in which cases the principal stratification framework has relatively high utility for the purpose of effect modification analysis and is closely connected to the treatment marker selection problem. The results are illustrated with application to a vaccine efficacy trial, where ACN and ACS for an antibody marker are found to be consistent with the data and hence support the Prentice definition and consistency.

scholarly journals VALIDATION OF SURROGATE ENDPOINTS IN ADVANCED SOLID TUMORS: SYSTEMATIC REVIEW OF STATISTICAL METHODS, RESULTS, AND IMPLICATIONS FOR POLICY MAKERS

2014 ◽  
Vol 30 (3) ◽  
pp. 312-324 ◽  
Author(s):  
Oriana Ciani ◽  
Sarah Davis ◽  
Paul Tappenden ◽  
Ruth Garside ◽  
Ken Stein ◽  
...  
Keyword(s):  
Solid Tumors ◽  
Statistical Methods ◽  
Surrogate Endpoint ◽  
Cytotoxic Agents ◽  
Surrogate Endpoints ◽  
Treatment Level ◽  
Cancer Type ◽  
Policy Makers ◽  
New Therapies ◽  
Advanced Tumor

Objectives: Licensing of, and coverage decisions on, new therapies should rely on evidence from patient-relevant endpoints such as overall survival (OS). Nevertheless, evidence from surrogate endpoints may also be useful, as it may not only expedite the regulatory approval of new therapies but also inform coverage decisions. It is, therefore, essential that candidate surrogate endpoints be properly validated. However, there is no consensus on statistical methods for such validation and on how the evidence thus derived should be applied by policy makers.Methods: We review current statistical approaches to surrogate-endpoint validation based on meta-analysis in various advanced-tumor settings. We assessed the suitability of two surrogates (progression-free survival [PFS] and time-to-progression [TTP]) using three current validation frameworks: Elston and Taylor's framework, the German Institute of Quality and Efficiency in Health Care's (IQWiG) framework and the Biomarker-Surrogacy Evaluation Schema (BSES3).Results: A wide variety of statistical methods have been used to assess surrogacy. The strength of the association between the two surrogates and OS was generally low. The level of evidence (observation-level versus treatment-level) available varied considerably by cancer type, by evaluation tools and was not always consistent even within one specific cancer type.Conclusions: Not in all solid tumors the treatment-level association between PFS or TTP and OS has been investigated. According to IQWiG's framework, only PFS achieved acceptable evidence of surrogacy in metastatic colorectal and ovarian cancer treated with cytotoxic agents. Our study emphasizes the challenges of surrogate-endpoint validation and the importance of building consensus on the development of evaluation frameworks.

Is Suicide Ideation a Surrogate Endpoint for Geriatric Suicide?

2005 ◽  
Vol 35 (2) ◽  
pp. 193-205 ◽  
Author(s):  
Paul S. Links ◽  
Marnin J. Heisel ◽  
Adam Quastel
Keyword(s):  
Suicide Ideation ◽  
Surrogate Endpoint

scholarly journals Meta-regression of randomized control trials with antithrombotics: weak correlation between net clinical benefit and all cause-mortality

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Roubi Kilo ◽  
Silvy Laporte ◽  
Rama Arab ◽  
Sabine Mainbourg ◽  
Steeve Provencher ◽  
...  
Keyword(s):  
Clinical Benefit ◽  
Surrogate Endpoint ◽  
Weak Correlation ◽  
Surrogate Outcome ◽  
Randomized Controlled ◽  
Relative Risks ◽  
All Cause Mortality ◽  
Prevention Studies ◽  
Randomized Control ◽  
Net Clinical Benefit

AbstractThis study aimed to explore the validity of the use of the net clinical benefit (NCB), i.e. the sum of major bleeding and thrombotic events, as a potential surrogate for all-cause mortality in clinical trials assessing antithrombotics. Published randomized controlled trials testing anticoagulants in the prevention or treatment of venous thromboembolism (VTE) and non-valvular atrial fibrillation (NVAF) were systematically reviewed. The validity of NCB as a surrogate endpoint was estimated by calculating the strength of correlation of determination (R2) and its 95% confidence interval (CI) between the relative risks of NCB and all-cause mortality. Amongst the 125 trials retrieved, the highest R2trial values were estimated for NVAF (R2trial = 0.41, 95% CI [0.03; 0.48]), and acute VTE (R2trial = 0.30, 95% CI [0.04; 0.84]). Conversely, the NCB did not correlate with all-cause mortality in prevention studies with medical (R2trial = 0.12, 95% CI [0.00; 0.36]), surgical (R2trial = 0.05, 95% CI [0.00; 0.23]), and cancer patients (R2trial = 0.006, 95% CI [0.00; 1.00]). A weak correlation between NCB and all cause-mortality was found in NVAF and acute VTE, whereas no correlation was observed in clinical situations where the mortality rate was low. Consequently, NCB should not be considered a surrogate outcome for all cause-mortality in anticoagulation trials.

scholarly journals Trends in Phase II Trials for Cancer Therapies

Cancers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 178
Author(s):  
Faruque Azam ◽  
Alexei Vazquez
Keyword(s):  
Phase Ii ◽  
Null Model ◽  
Surrogate Endpoint ◽  
Response Rates ◽  
Drug Combinations ◽  
Phase Iii ◽  
Cancer Drug ◽  
Cancer Therapies ◽  
Targeted Agents ◽  
Phase Ii Trials

Background: Drug combinations are the standard of care in cancer treatment. Identifying effective cancer drug combinations has become more challenging because of the increasing number of drugs. However, a substantial number of cancer drugs stumble at Phase III clinical trials despite exhibiting favourable efficacy in the earlier Phase. Methods: We analysed recent Phase II cancer trials comprising 2165 response rates to uncover trends in cancer therapies and used a null model of non-interacting agents to infer synergistic and antagonistic drug combinations. We compared our latest efficacy dataset with a previous dataset to assess the progress of cancer therapy. Results: Targeted therapies reach higher response rates when used in combination with cytotoxic drugs. We identify four synergistic and 10 antagonistic combinations based on the observed and expected response rates. We demonstrate that recent targeted agents have not significantly increased the response rates. Conclusions: We conclude that either we are not making progress or response rate measured by tumour shrinkage is not a reliable surrogate endpoint for the targeted agents.

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