Development↦Statistic Methodology↦Statistics in the Protocol↦Study Termination Criteria
What is it? Why is it important?
Predefined rules regulate the premature discontinuation of a study. These rules are:
- Defined based on a risk-based approach (e.g. right and safety of study participants, data quality)
- Decumented in the study protocol and, if applicable, in the Statistical Analysis Plan (SAP)
- Assessed during planned interim analyses
Early termination criteria may include:
- Safety: unacceptable safety risks to participants (e.g. a higher number of adverse events in the intervention group compared to the control group, resulting in an unacceptable risk-benefit-ratio)
- Futility: an interim analysis indicates, with a high probability, that the intervention is ineffective or has only minimal benefit
- Efficacy: clear and statistically significant treatment benefit, making it unethical to continue the study with the inclusion of a control / placebo group
Interim analyses need careful planning because they can increase the risk of type I errors (false positives), thereby affecting the trial power. Poorly planned interim analyses can compromise trial results.
What do I need to do?
As a SP-INV, assess risks threating the study`s Critical to Quality factors, and if necessary define:
- The need, timing and frequency of interim analyses to assess discontinuation criteria (i.e. when and how often to assess discontinuation criteria during study conduct
If one or more interim analyses are needed:
- Discuss the interim analyses with a statistician, as they may affect the sample size calculation
- Describe the analyses in the study protocol, including the type, timing, and frequency of the analyses
- Organise the requirement and composition of an Independent Data Monitoring Committee (IDMC) (i.e. also referred to as an independent Data Safety Monitoring Board (DSMB – with a focus on safety). An IDMC/DSMB evaluates the results of the interim analysis and makes impartial recommendations regarding the continuation/early termination of an ongoing study
Where can I get help?
Your local Research Support Centre↧ can assist you with experienced staff regarding this topic
Basel, Departement Klinische Forschung (DKF), dkf.unibas.ch
Lugano, Clinical Trials Unit (CTU-EOC), ctueoc.ch
Bern, Department of Clinical Research (DCR), dcr.unibe.ch
Geneva, Clinical Research Center (CRC), crc.hug.ch
Lausanne, Clinical Research Center (CRC), chuv.ch
St. Gallen, Clinical Trials Unit (CTU), h-och.ch
Zürich, Clinical Trials Center (CTC), usz.ch
SCTO Research Tools & Resources
Video
References
ICH GCP E6 (R3) – see in particular
- 2.6 Investigator: Premature termination or suspension of a trial
- 3.10.1 Risk management
- 3.17.1 Reports: The premature termination or suspnesion of a trial
ICH Topic E9 – see in particular
- 4.1 Trial monitoring and interim analysis
- 4.5 Interim analysis and early stopping
- 7.2.1 Efficacy data
- 7.2.2 Safety data