Table 1.

Glossary of basic terms related to platform trials

Main definitions
Adaptive designs for clinical trials: an adaptive trial uses data that accumulates during the study to modify study elements in a flexible though prespecified manner. Elements that may be modified include the sample size, end points, eligible populations, randomization ratio, and interventions.
Master protocol: overarching trial characteristics and rules guiding several parallel subtrials (either concomitant or sequential) under the same protocol and governance structure.
Multiarm multistage (MAMS) trials: adaptive design and set-up that aims to answer multiple questions simultaneously under the same regulatory framework. Several different treatment options can be compared simultaneously, usually against a single control arm. Tested treatments can be different drugs at single dosages, a combination of drugs, or various doses of the same drug. Adaptation rules and interim analyses allow for changes in the subtrials/arms that constitute part of the trial. The master protocol of MAMS can be adopted in different forms.
Basket and umbrella trials: both are multiarm, often adaptive designs of randomized clinical trials under a master protocol. In the former, multiple diseases or phenotypes are treated with the same treatment, whereas in the latter, multiple treatments are tested against the same disease.
Platform trials: derivation of MAMS that consist of a prospective, disease-focused, adaptive, randomized clinical trial that compares multiple interventions against a single, constant control group.
Bayesian statistics: a statistical set of methods characterized by an approach in which probability expresses the degree of certainty of an event to happen within a timeframe. In platform trials, this allows us to decide whether to continue or discontinue an arm containing active treatment on the basis of interim analysis and the prediction that the drug may or may not achieve a certain threshold of efficacy (i.e. futility/efficacy stop rules).
Specific Appendices (Domain and Intervention specific): these appendices contain the specific details that concern each subtrial or arm that is incorporated into the platform trial, whereas the master protocol provides the overarching information.
Integrated Research Platform: the combination of the governing bodies, the network of clinical sites, the methodological tools including the master protocol, and the regulatory and legal aspects that allow setting up a platform trial.