How COVID broke the evidence pipeline

It wasn’t long into the pandemic before Simon Carley realized we had an evidence problem. It was early 2020, and COVID-19 infections were starting to lap at the shores of the United Kingdom, where Carley is an emergency-medicine doctor at hospitals in Manchester. Carley is also a specialist in evidence-based medicine — the transformative idea that physicians should decide how to treat people by referring to rigorous evidence, such as clinical trials.

As cases of COVID-19 climbed in February, Carley thought that clinicians were suddenly abandoning evidence and reaching for drugs just because they sounded biologically plausible. Early studies Carley saw being published often lacked control groups or enrolled too few people to draw firm conclusions. “We were starting to treat patients with these drugs initially just on what seemed like a good idea,” he says. He understood the desire to do whatever is possible for someone gravely ill, but he also knew how dangerous it is to assume a drug works when so many promising treatments prove to be ineffective — or even harmful — in trials.

A landmark programme to test potential COVID-19 therapies in dozens of countries is restarting with a fresh roster of treatments — this time aimed at tempering the raging immune responses that can worsen severe disease.