A US government advisory panel has convened to decide whether to endorse mass use of Pfizer’s Covid-19 vaccine to help conquer the outbreak that has killed close to 300,000 Americans. The meeting of outside advisers to the Food and Drug Administration (FDA) represented the penultimate hurdle before the expected start of the biggest vaccination campaign in US history. Depending on how fast the FDA signs off on the panel’s recommendation, shots could begin within days. The FDA panel functions like a science court. During the scheduled day-long session, it was expected to debate and pick apart the data – in public and live-streamed – on whether the vaccine is safe and effective enough to be cleared for emergency use.