Once the trial effectively became single arm, and with no ECA patient level characteristic similarities, the trial was compromised. Do not discount the screening selection of only the "healthiest" patients in order provide enough time for L to kick in and to monitor for PFS.
To the best of my knowledge regulators never approved the trial changes in real time.
>>It is essential to have constructive input from regulators on the study protocol, analytic approach, selection of RWD sources, endpoint definitions, and other key aspects of the project to avoid miscommunication and surprises down the line.