Ten more Covid-19 diagnostics received emergency use authorisation from the US FDA last week – among them a test for IL-6. Perhaps the agency believes that IL-6-targeting drugs could still have a role to play, despite several failures. Beckman Coulter’s Access IL-6 test, which got the nod on Thursday, joins Roche’s Elecsys IL-6 test, authorised in June. Both are used to identify Covid-19 patients who could be at high risk of needing mechanical ventilation – IL-6 has been found to be elevated in some patients with severe disease. Beckman says that monitoring IL-6 levels could help doctors treat patients before they need a ventilator, but it does not specify what this treatment might be. The jury is still out on anti-IL-6 MAbs: Sanofi’s Kevzara has flopped twice, while Roche’s Actemra failed in the Covacta study. However, more recently, Roche claimed a win in the Empacta trial, with hospitalised patients receiving Actemra 44% less likely to progress to mechanical ventilation or death than those receiving placebo. Still, there was no difference in mortality. The Remdacta study, of Actemra in combination with Gilead’s remdesivir, is yet to read out.