In an OLE trial patients will know they are on the drug rather than placebo. Know you will get drug in the OLE tends to be the incentive to join a RCT.
“Do they not know what drug they're on even once it's open-label?”
Patients are often not told if they were on drug or placebo during the main trial. Although in some cases it may seem clear to some they were on drug.
There is ethical debates on whether patients should/have a right to know after an RCT if they were on drug or not. Also before deciding on joining the OLE. This might limit how many joins an OLE if they know they were on drug and had no real effect or indeed had side effects.
As I understand in most trials patients / caregivers are asked to sign not to squeal, but if they don’t know there is less value in squealing.
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