What action should an investigator take upon receipt of supplies?

Upon receipt of supplies, the investigator's immediate responsibility is to verify the shipment and product information. This action is crucial for ensuring the integrity and suitability of the clinical trial materials. Verification involves checking that the supplies match the order placed, confirming that they are within their expiration dates, and assessing their condition to ensure they have not been compromised during shipping.

This step is vital to maintain compliance with Good Clinical Practice (GCP) and to ensure that only appropriate materials are used in the research process. Accurate verification helps prevent issues that could arise from using incorrect or damaged supplies, which could adversely affect the study's validity and the safety of the participants.

Other options may seem plausible, but they do not align with the immediate priorities after receiving supplies. For instance, contacting the regulatory authority may only be necessary in specific circumstances, and starting patient enrollment can only happen after the supplies have been confirmed to be in good condition and compliant with the study protocol. Discarding damaged supplies without proper assessment may lead to unnecessary waste and loss of necessary materials. Therefore, verifying the shipment and product information is the most prudent and essential action for the investigator.