placebo
This refers to a 'dummy' drug given to a group of patients who are participating in a clinical trial. Their appearance is exactly the same as the actual drug being tested. It had been thought that using a placebo was needed to see if the actual drug made an improvement for the patient - and not from any additional care given by the physician or the patient's overall positive attitude.
There has been a campaign in recent years to end the use of a placebo. It is felt when a patient is seriously ill from being a non responder to the first - and often second line of therapy - they do not have that 6 months to several years' time to waste on possibly taking a placebo as part of the clinical trial. That precious time for the patient is 'lost' so to speak especially if they are receiving the placebo when they could be taking the actual drug. I'm sure we have not heard the end of this endeavor.