People everywhere are clinging to the hope that there'll soon be a coronavirus vaccine. That aspiration suffered a setback last week when AstraZeneca announced the suspension of its trial of the Covid-19 vaccine it's developing. So how are decisions to start and stop clinical trials made, and what's the present trajectory for a coronavirus vaccine? Chris Smith asked Gordon Dougan, who's overseen the development of many vaccines during his career, to explain... Like this podcast? Please help us by supporting the Naked Scientists