I guess my post must have been unclear and incomplete as usual per catdoggy's complaints, whereas of course catdoggy's posts are always clear, complete and absolutely devoid of any useful information.
For an Open Label Extension, yes.
Patients joining a Randomised Controlled Trail (RCT) will also know which drug/treatment is being trialled and for what indication etc., but they won't know if they end up on the drug/treatment or placebo. This is what blinding a trial means and also applies to the staff, sponsor etc. who manage the trial until data is unlocked and analysed.
Still at the analysis stage I believe the identity of individual patients may be hidden and only accessible to some with a need to know. Hence, often at the end of a RCT patients are not told if they were on drug/treatment or placebo, but might well be able to make a qualified guess. Joining the OLE means that patients previously on drug/treatment continue to (hopefully) benefit and those on placebo are assured drug/treatment. Generally there is no patient charge during both the RCT and OLE, plus certain expenses may be covered by the trail, e.g. travel. Potentially further extensions, as we have seen with Anavex trials and beyond through regulatory special access schemes may go on for ex-trial patients until the drug is either approved or rejected.
All of this also ethically linked to P4 commercial post Accelerated Approvals, where really patients are participating in a clinical trial, but must pay (through insurance and/or privately). This versus running e.g. P3 confirmatory trial where patients do not pay, but may need to wait for the OLE to know they actually get drug/treatment.
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