In a phase II clinical trial that assess the safety and tolerability of an investigational product versus placebo, do we normally consider a tolerability rate for the placebo group? Do we expect them to be very compliant and rarely miss does?
Hi,
Depends mainly on the power to detect a difference between the groups. tolerability will be same as the active group.
Most trials with placebo arm are double blinded and so it would be hard to differentiate between tolerability between the two arms and so it cant be rated. Besides, a placebo is just a placebo, not the active IMP. Yes, there is equal compliance measures. This is very critical in obtaining high quality and verifiable data.
with few exceptions, the use of placebo groups as a control will be coupled with the investigators and the patients blinded, to control bias.
the safety data collected in the placebo arm are very important. It helps to make the different between the “expectation bias” and other safety events that are reportes in both groups (like often fatigue …) and the ones that are more frequently present in the active arm.