Drug Evaluation Committee 2014-42 Consent Acquisition and Pre-Treatment Drug Wash-out
Related classification: Obtaining consent
First published: Feb 2015
Revised publication date: April 2015
Question
I have a question regarding the relationship between obtaining consent and concomitant use of prohibited drugs (wash-out of pre-treatment drugs).
In the protocol for an international clinical trial, it is stipulated that the period during which concomitant use of a concomitantly prohibited drug is prohibited is 4 weeks prior to the start of administration of the investigational drug. In this case, the monitor explained to me that in Japan, the prohibited drug is discontinued after consent is obtained and the wash-out is done, but in a global clinical trial, the drug must be discontinued before consent is obtained.
The monitor explained that in international clinical trials, it is necessary to discontinue the drug before obtaining consent. It was explained to me that it is unethical to stop concomitant medications for the purpose of a clinical trial after obtaining consent. I understand what he meant, but I don't think it is acceptable to stop the drug before obtaining consent in order to meet the schedule of the clinical trial. I was pointed out that there is a possibility of a problem if wash-out is done after consent is obtained.
Opinion of the Pharmaceutical Manufacturers Association of Japan (PMAJ)
There is no difference between Japanese GCP and ICH-GCP in terms of the necessity of providing written explanation to subjects and obtaining their consent prior to participation in a clinical trial (see GCP Article 1 Guidance 2(9)/GCP Article 50, Paragraph 1 and ICH-GCP 2.9/ICH-GCP 4.8.8).
Discontinuation of the administration of a prohibited concomitant drug (i.e., the current therapeutic drug) as defined in the study protocol for the purpose of entry into a clinical trial is considered an action associated with the clinical trial. Therefore, when such action is taken, it is necessary to explain to the subject and obtain consent using a document approved by the Clinical Trial Review Committee (an explanatory document clearly stating the washout) in advance.
Reason for revision of opinion
Some wording has been revised and minor changes have been made.