Sunday, March 05, 2017

Inclusion/exclusion violations, protocol deviations, protocol deviation waiver, rescreening, and others

In one of my previous posts, I discussed "Protocol Deviation versus Protocol Violation and its Classifications (minor, major, critical, important)". There are some more aspects related to the protocol deviations. 

Pre and post randomization protocol deviations

Protocol deviations should be collected throughout the study (beyond only the inclusion /exclusion criteria). If it is a randomized study, we can classify the protocol deviations as pre-randomization and post randomization. If it is non-randomized study, we can classify the protocol deviations as pre-dose and post-dose. 

Prior to the randomization or dosing, the eligibility criteria (inclusion and exclusion criteria) should be verified. If subjects do not meet any of the inclusion and exclusion criteria, but are enrolled into the study, the violation of inclusion/exclusion criteria must be recorded. Some people may use the term 'protocol violation' specifically for those deviations that are related to the inclusion and exclusion criteria. 

Post-randomization protocol deviations can include anything that deviates from the study protocol: study drug compliance, taking prohibited concomitant medication, subject unblinding of treatment assignments, outside the visit window, missing visits, missing procedures,…

According to the SDTM implementation guide, the pre-randomization protocol deviations (i.e., violation of inclusion/exclusion criteria) should be collected in IE domain and the post-randomization protocol deviations need to be collected in DV domain.

Can we allow the protocol deviation waiver? 

A protocol waiver is an intentional deviation from the approved protocol, such as the enrollment of a participant in violation of the protocol’s inclusion/exclusion criteria. Most sites realize that it is necessary to obtain the sponsor’s approval prior to implementing a protocol waiver. It is also necessary, however, to obtain the IRB’s approval prior to implementing a protocol waiver, unless the change is deemed necessary to eliminate an apparent immediate hazard for study participants' safety. In practice, many clinical trial sponsors will allow the protocol deviation waiver and allow the subjects without meeting one or more inclusion / exclusion criteria to be enrolled into the study. Here are some discussions about the waiver for protocol deviations: 

EMA on its website has a specific question about the protocol waivers:
Adherence to the protocol is a fundamental part of the conduct of a clinical study. Any significant change to the protocol should be submitted as an amendment to the competent regulatory authority and ethics committee. Significant changes to the protocol include any change in inclusion and exclusion criteria, addition or deletion of tests, dosing, duration of treatment etc (see the definition of a substantial amendment in the 'detailed guidance for the request for authorisation of a clinical trial on a medicinal product for human use to the competent authorities, notification of substantial amendments and declaration of the end of the trial' published by the European Commission in chapter I, volume 10 of the rules governing medicinal products in the European Community).  Deviations from the inclusion/exclusion criteria of the protocol might erode the scientific and ethical value of the protocol and its authorisation and might have an impact on the processes put in place for the care and safety of the study subjects.
Sponsors and investigators should not use systems of prospectively approving protocol deviations, in order to effectively widen the scope of a protocol.   Protocol design should be appropriate to the populations required and if the protocol design is defective, the protocol should be amended.
GCP does permit deviations from the protocol when necessary to eliminate immediate hazards to the subjects but this should not normally arise in the context of inclusion/exclusion criteria, since the subject is not yet fully included in the trial at that point in the process GCP inspectors have observed a number of sponsors implementing systems where the investigator can contact the sponsor, usually the Medical Monitor, and request a prospective approval to deviate from the inclusion and/or exclusion criteria.  The use of such systematic waiver systems in clinical trials is not considered to be appropriate and studies using such a system might be regarded as non-compliant with GCP.
Can we allow rescreening for subjects who failed one of the inclusion / exclusion criteria?

For some inclusion/exclusion criteria that are based on the laboratory measurements, lung functional test, six-minutes walking test,… subjects may be screening failures due to not meeting one of the criteria. For example, if one of the inclusion criteria requires hemoglobin level must be greater than 9 g/dl, a subject may just miss the criteria (for example, hemoglobin level is 8.9 g/dl) that could be caused by the measurement error. If the protocol specifies that the rescreening is allowed, the subject may come back for a rescreening and have another lab test for hemoglobin level. I have seen many clinical trial protocols that allow the rescreening, especially in the chronic disease clinical trials.

It is obvious that the rescreening will not be feasible for clinical trials in acute diseases for example, in clinical trials in ischemic stroke patients.   

Where to document and maintain the protocol deviations?

The protocol deviations are usually documented by the clinical team (study manager and clinical monitors) and oversight group. In early days, the protocol deviation may just be entered and maintained in an excel spreadsheet. Nowadays, the protocol deviations are usually documented and maintained in CTMS (clinical trial management system).

Can protocol deviations be collected through EDC?

The protocol deviations can also be directly documented and maintained within EDC system where a separate case report form (CRF) is designed specifically for collecting the protocol deviations. Clinical monitors (CRAs) are given the access to enter and maintain the protocol deviation through EDC system. The investigator/study coordinators at sites will not have access to the protocol deviation CRF. 

Site level versus subject level protocol deviations
While majority of the protocol deviations are on the subject level, the protocol deviations can be on the site-level that have impacts on all subjects enrolled at that specific site.

The site level and subject level protocol deviation need to be distinguished in the protocol deviation tracking.

CDISC SDTM implementation guide indicates that the protocol deviations will be captured in DV domain (see the explanations of the DV domain below). Notice that current SDTM standard is designed for subject data with the only exception of Trial Design info. Therefore, the DV domain is only for the subject-level protocol deviations. If there are site level protocol deviation (violations), the suggestion is not to be included in the DV dataset, but included in protocol deviation tracking and described in the clinical study report. It is also a good practice to indicate in Study Data Reviewer’s Guide how the site-level protocol deviations are handled.



How will the protocol deviation information be used?

The protocol deviation information will be converted into the data set as part of the clinical database.

The protocol deviations in DV domain will be provided in data listing and will be summarized (by treatment group and by protocol deviation category). The violation of the inclusion/exclusion criteria may be separately listed and summarized.

In clinical study report, according to ICH E3, section 10.2 is for describing the inclusion / exclusion criteria violation and protocol deviations


1 comment:

Liz MacDonald said...

Do you have experience creating the DV domain? We are struggling to figure out how to find the controlled terminology to use for the DVDECOD column - do you have any insight on that?