What happens to the participants at the end of the trial? Do they stop taking the drug, or can they continue if it has proven effective?

It depends on the study. For some trials, especially phase 2 trials, the end of the study means the end of taking the drug.

Some phase 3 studies will have so-called open-label extensions. In this case, after completing the initial placebo-controlled phase, the research team will allow participants to join an extension study where they will receive the actual drug.

If the drug is approved, the local NHS authority and NICE guidance will take over. They will assess factors such as effectiveness, safety, and economic viability.