Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

Background: Many patients with COVID-19 have been treated with plasma containing anti-SARS-CoV-2 antibodies. We aimed to evaluate the safety and efficacy of convalescent plasma therapy in patients admitted to hospital with COVID-19. Methods: This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. The trial is underway at 177 NHS hospitals from across the UK. Eligible and consenting patients were randomly assigned (1:1) to receive either usual care alone (usual care group) or usual care plus high-titre convalescent plasma (convalescent plasma group). The primary outcome was 28-day mortality, analysed on an intention-to-treat basis. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings: Between May 28, 2020, and Jan 15, 2021, 11558 (71%) of 16287 patients enrolled in RECOVERY were eligible to receive convalescent plasma and were assigned to either the convalescent plasma group or the usual care group. There was no significant difference in 28-day mortality between the two groups: 1399 (24%) of 5795 patients in the convalescent plasma group and 1408 (24%) of 5763 patients in the usual care group died within 28 days (rate ratio 1·00, 95% CI 0·93–1·07; p=0·95). The 28-day mortality rate ratio was similar in all prespecified subgroups of patients, including in those patients without detectable SARS-CoV-2 antibodies at randomisation. Allocation to convalescent plasma had no significant effect on the proportion of patients discharged from hospital within 28 days (3832 [66%] patients in the convalescent plasma group vs 3822 [66%] patients in the usual care group; rate ratio 0·99, 95% CI 0·94–1·03; p=0·57). Among those not on invasive mechanical ventilation at randomisation, there was no significant difference in the proportion of patients meeting the composite endpoint of progression to invasive mechanical ventilation or death (1568 [29%] of 5493 patients in the convalescent plasma group vs 1568 [29%] of 5448 patients in the usual care group; rate ratio 0·99, 95% CI 0·93–1·05; p=0·79). Interpretation: In patients hospitalised with COVID-19, high-titre convalescent plasma did not improve survival or other prespecified clinical outcomes. Funding: UK Research and Innovation (Medical Research Council) and National Institute of Health Research

Local-scale variability in the diet of Black-legged Kittiwakes Rissa tridactyla

The Black-legged Kittiwake Rissa tridactyla is a small gull that is widely distributed in the North Atlantic and Pacific. During the breeding season it feeds mainly on fish and, in the North Sea, the Lesser Sandeel Ammodytes marinus typically forms the main species in the diet. We compared the diet and breeding performance of Kittiwakes at four colonies in east Britain with potentially overlapping foraging ranges where both Lesser Sandeels and alternative prey (clupeids: Sprat Sprattus sprattus and Herring Clupea harengus) were potentially available. During the four years of the study Kittiwakes at all four colonies showed similar within-season shifts in the age class of sandeel taken with older (1+ group) fish being replaced by young of the year (0 group). However, in every year the predominant prey differed between the two marine colonies, where birds fed mainly on sandeels, and the two estuarine colonies, where clupeids were the most important prey. We suggest that these dietary differences reflect differences in foraging areas such that Kittiwakes from marine colonies feed offshore in areas with a sandy seabed, habitat favoured by sandeels, and birds from estuarine colonies feed closer inshore in areas with a more rocky seabed, habitat favoured by clupeids. Breeding success of Kittiwakes at the four colonies followed a similar trend over the first three years but the marked increase recorded at the marine colonies in 2000 was not apparent at the estuarine colonies