How a new medicine is tested in each trial phase and why it can still failFrom safety checks on a handful of volunteers to post‑marketing surveillance, every stage of clinical testing asks a different question – and a positive result in one does not guarantee success in the next.11 October 2026
Why most promising new drugs fail before they reach the chemistOnly a tiny fraction of candidate medicines make it through clinical trials, as each successive phase asks a fundamentally different question.11 September 2026
