Components of a Compliant Clinical Trial Protocol
Part of Good Clinical Practice (GCP) — ICH E6(R3): Clinical Trial Protocol and Design.
About 6 minutes. Free, in your language, no account needed.
Why this matters
The protocol is the rulebook for the study. Every eligibility decision, every visit, every deviation call traces back to it. If you cannot find the rule in the protocol, you cannot defend the action to a monitor or an inspector.
The protocol is the rulebook
A protocol defines four things. Why the trial is being done. Who can participate. What will be done and measured. How safety and data will be managed.
The International Council for Harmonisation (ICH) guideline ICH E6(R3) defines a protocol as a document that describes the objectives, design, methodology, statistical considerations and organization of a trial. Its Glossary adds a point that matters. Throughout E6(R3), "protocol" means the protocol and its amendments together.
In daily site work, the protocol answers three questions:
- Was this participant eligible? — check the inclusion and exclusion criteria.
- Should this procedure have been done at this visit? — check the schedule of events.
- Is this a protocol deviation? — compare what happened against what the protocol required.
What E6(R3) expects a protocol to be
Principle 8 states that clinical trials should be described in a clear, concise, scientifically sound and operationally feasible protocol. Principle 8.1 says a well-designed protocol is fundamental to protecting participants and generating reliable results. Principle 8.2 requires the scientific objectives to be clear and explicitly stated. Principle 8.3 extends the same standard to the execution plans: the statistical analysis plan, the data management plan and the monitoring plan.
Appendix B opens with a related instruction. The protocol should be designed to minimize unnecessary complexity and to mitigate or eliminate important risks. It also introduces a new idea:
"Building adaptability into the protocol, for example, by including acceptable ranges for specific protocol provisions, can reduce the number of deviations or in some instances the requirement for a protocol amendment."
Adaptability must not weaken participant safety or scientific validity. But a protocol with a realistic visit window produces fewer deviations than one without.
The Appendix B contents, B.1 to B.16
Appendix B lists the topics a protocol should generally include. The contents may vary with the trial design. Learn these sixteen headings, because monitors and inspectors use them.
| Section | Topic | What it settles |
|---|---|---|
| B.1 | General Information | Title, protocol number, date, sponsor, signatories |
| B.2 | Background Information | Product description, nonclinical and clinical findings, known risks and benefits, population |
| B.3 | Trial Objectives and Purpose | The scientific objectives; estimands where defined |
| B.4 | Trial Design | Endpoints, design type, randomization and blinding, dosing, schedule of events, stopping rules, code-breaking |
| B.5 | Selection of Participants | Inclusion criteria, exclusion criteria, screening mechanism |
| B.6 | Discontinuation and Withdrawal | When and how participants stop; what data are still collected |
| B.7 | Treatment and Interventions | Treatments, permitted and prohibited medications, adherence monitoring |
| B.8 | Assessment of Efficacy | Efficacy parameters and their timing |
| B.9 | Assessment of Safety | Safety parameters, adverse event reporting, follow-up |
| B.10 | Statistical Considerations | Methods, sample size, analysis populations, missing data |
| B.11 | Direct Access to Source Records | The right of monitors, auditors, inspectors and the IRB/IEC to see source |
| B.12 | Quality Control and Quality Assurance | Critical to quality factors, risks, mitigations, monitoring approach, noncompliance handling |
| B.13 | Ethics | Ethical considerations for the trial |
| B.14 | Data Handling and Record Keeping | Data to be collected, what counts as source, retention |
| B.15 | Financing and Insurance | If not in a separate agreement |
| B.16 | Publication Policy | If not in a separate agreement |
Three of these changed in emphasis under R3.
B.12.1 asks the protocol to describe the identified critical to quality factors, the associated risks and the risk mitigation strategies, unless documented elsewhere. Risk thinking now sits inside the protocol.
B.14.2 asks the protocol to identify which data are recorded directly into a data acquisition tool with no prior written or electronic record. Those entries are the source record. Deciding this before enrollment prevents the most common source-documentation dispute. B.4.2 also names trials with decentralized elements as a design type the protocol should describe.
Amendments and version control
Amendments are normal. New safety information, slow recruitment or a regulatory change can all require one. What matters is sequence.
Section 1.4.7 states that no deviations from, or changes to, the protocol should be started without prior documented IRB/IEC approval or favorable opinion of an appropriate amendment. There are two exceptions. The first is a change necessary to eliminate an immediate hazard to participants. The second, where applicable regulatory requirements allow it, is a change that involves only logistical or administrative aspects.
Section 2.5.4 makes the site rule plain. Follow the protocol, and deviate only where necessary to eliminate an immediate hazard. Then inform the sponsor promptly. Section 2.5.5 adds that the investigator reports the hazard, the change made and any proposed amendment to the IRB/IEC and, where applicable, the regulatory authority.
In practice
Amara coordinates a Phase III hypertension site. Amendment 3 was approved by the IRB/IEC on 9 March. It removes one exclusion criterion and adds a 12-week echocardiogram.
Amara does four things before using it. She files the IRB/IEC approval letter. She confirms the sponsor released the amended protocol and the revised consent form. She trains the team and records it. She marks the old protocol superseded.
On 11 March she screens a participant who would have been excluded under Amendment 2. Amendment 3 is approved and implemented at the site, so the participant is eligible. Amara records the protocol version in the screening notes.
A site that enrolled the same person on 5 March, before approval, would have an eligibility deviation, because nobody tracked the version.
The version in effect at the site on the day of the visit governs the visit.
Key takeaways
- The clinical trial protocol is the rulebook for the study, and in ICH E6(R3) the term "protocol" includes its amendments.
- Principle 8 requires the protocol to be clear, concise, scientifically sound and operationally feasible, and extends that requirement to the statistical, data management and monitoring plans.
- Appendix B lists the protocol contents as sections B.1 to B.16, and the contents may vary with the trial design.
- Section B.12.1 places critical to quality factors, their risks and the mitigation strategies inside the protocol unless they are documented elsewhere.
- Section B.14.2 requires the protocol to identify which data are entered directly into a data acquisition tool and are therefore the source record.
- Under section 1.4.7 no protocol change may be started before documented IRB/IEC approval, except to eliminate an immediate hazard or, where permitted, for purely logistical or administrative changes.