Final answer:
The investigators should amend the protocol, get IRB approval, notify the institutions, and provide updated guidelines to ensure patient safety and informed consent.
Step-by-step explanation:
When the investigators decide to change the time of infusion of a study drug in a protocol, they must follow specific procedures at each institution. First, they must amend the protocol to include the new guidelines for the time of infusion. The amended protocol should be approved by the Institutional Review Board (IRB) at each institution. The investigators should then notify the participating institutions about the change and provide them with the updated protocol. Subsequent patients enrolled in the study should receive treatment according to the new guidelines.
It is important for the investigators to ensure patient safety and inform the participants about any changes in the protocol. The participants should provide informed consent for the new treatment guidelines, understanding the potential risks and benefits. The investigators should also document the changes and communicate them to the relevant regulatory authorities.