
Morgan MacLeod
· Theoretical and Computational AstrophysicistVerifiedHarvard University · Astronomy
Active 1962–2024
Research topics
- Medicine
- Internal medicine
- Emergency medicine
- Surgery
- Intensive care medicine
- Pediatrics
- Anesthesia
- Physical therapy
- Virology
Selected publications
The Lancet Child & Adolescent Health · 2024 · 34 citations
- Medicine
- Internal medicine
- Virology
BACKGROUND: Paediatric multisystem inflammatory syndrome temporally associated with SARS-CoV-2 (PIMS-TS), also known as multisystem inflammatory syndrome in children (MIS-C) emerged in April, 2020. The paediatric comparisons within the RECOVERY trial aimed to assess the effect of intravenous immunoglobulin or corticosteroids compared with usual care on duration of hospital stay for children with PIMS-TS and to compare tocilizumab (anti-IL-6 receptor monoclonal antibody) or anakinra (anti-IL-1 receptor antagonist) with usual care for those with inflammation refractory to initial treatment. METHODS: We did this randomised, controlled, open-label, platform trial in 51 hospitals in the UK. Eligible patients were younger than 18 years and had been admitted to hospital for PIMS-TS. In the first randomisation, patients were randomly assigned (1:1:1) to usual care (no additional treatments), usual care plus methylprednisolone (10mg/kg per day for 3 consecutive days), or usual care plus intravenous immunoglobulin (a single dose of 2 g/kg). If further anti-inflammatory treatment was considered necessary, children aged at least 1 year could be considered for a second randomisation, in which patients were randomly assigned (1:2:2) to usual care, intravenous tocilizumab (12 mg/kg in patients <30 kg; 8mg/kg in patients ≥30 kg, up to a maximum dose of 800 mg), or subcutaneous anakinra (2 mg/kg once per day in patients ≥10 kg). Randomisation was by use of a web-based simple (unstratified) randomisation with allocation concealment. The primary outcome was duration of hospital stay. Analysis was by intention to treat. For treatments assessed in each randomisation, a single Bayesian framework assuming uninformative priors for treatment was used to jointly assess the efficacy of each intervention compared with usual care. The trial was registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). FINDINGS: Between May 18, 2020, and Jan 20, 2022, 237 children with PIMS-TS were enrolled and included in the intention-to-treat analysis. Of the 214 patients who entered the first randomisation, 73 were assigned to receive intravenous immunoglobulin, 61 methylprednisolone, and 80 usual care. Of the 70 children who entered the second randomisation (including 23 who did not enter the first randomisation), 28 were assigned to receive tocilizumab, 14 anakinra, and 28 usual care. Mean age was 9·5 years (SD 3·8) in the randomisation and 9·6 years (3·6) in the second randomisation. 118 (55%) of 214 patients in the first randomisation and 39 (56%) of 70 patients in the second randomisation were male. 130 (55%) of 237 patients were Black, Asian, or minority ethnic, and 105 (44%) were White. Mean duration of hospital stay was 7·4 days (SD 0·4) in children assigned to intravenous immunoglobulin and 7·6 days (0·4) in children assigned to usual care (difference -0·1 days, 95% credible interval [CrI] -1·3 to 1·0; posterior probability 59%). Mean duration of hospital stay was 6·9 days (SD 0·5) in children assigned to methylprednisolone (difference from usual care -0·7 days, 95% CrI -1·9 to 0·6; posterior probability 87%). Mean duration of hospital stay was 6·6 days (SD 0·7) in children assigned to second-line tocilizumab and 9·9 days (0·9) in children assigned to usual care (difference -3·3 days, 95% CrI -5·6 to -1·0; posterior probability >99%). Mean duration of hospital stay was 8·5 days (SD 1·2) in children assigned to anakinra (difference from usual care -1·4 days, 95% CrI -4·3 to 1·8; posterior probability 84%). Two persistent coronary artery aneurysms were reported among patients assigned to usual care in the first randomisation. There were few cardiac arrythmias, bleeding, or thrombotic events in any group. Two children died; neither was considered related to study treatment. INTERPRETATION: Moderate evidence suggests that, compared with usual care, first-line intravenous methylprednisolone reduces duration of hospital stay for children with PIMS-TS. Good evidence suggests that second-line tocilizumab reduces duration of hospital stay for children with inflammation refractory to initial treatment. Neither intravenous immunoglobulin nor anakinra had any effect on duration of hospital stay compared with usual care. FUNDING: Medical Research Council and National Institute of Health Research.
The Lancet Diabetes & Endocrinology · 2023 · 38 citations
- Medicine
- Emergency medicine
- Internal medicine
BACKGROUND: Empagliflozin has been proposed as a treatment for COVID-19 on the basis of its anti-inflammatory, metabolic, and haemodynamic effects. The RECOVERY trial aimed to assess its safety and efficacy in patients admitted to hospital with COVID-19. METHODS: In the randomised, controlled, open-label RECOVERY trial, several possible treatments are compared with usual care in patients hospitalised with COVID-19. In this analysis, we assess eligible and consenting adults who were randomly allocated in a 1:1 ratio to either usual standard of care alone or usual standard of care plus oral empagliflozin 10 mg once daily for 28 days or until discharge (whichever came first) using web-based simple (unstratified) randomisation with allocation concealment. The primary outcome was 28-day mortality; secondary outcomes were duration of hospitalisation and (among participants not on invasive mechanical ventilation at baseline) the composite of invasive mechanical ventilation or death. On March 3, 2023 the independent data monitoring committee recommended that the investigators review the data and recruitment was consequently stopped on March 7, 2023. The ongoing RECOVERY trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). FINDINGS: Between July 28, 2021 and March 6, 2023, 4271 patients were randomly allocated to receive either empagliflozin (2113 patients) or usual care alone (2158 patients). Primary and secondary outcome data were known for greater than 99% of randomly assigned patients. Overall, 289 (14%) of 2113 patients allocated to empagliflozin and 307 (14%) of 2158 patients allocated to usual care died within 28 days (rate ratio 0·96 [95% CI 0·82-1·13]; p=0·64). There was no evidence of significant differences in duration of hospitalisation (median 8 days for both groups) or the proportion of patients discharged from hospital alive within 28 days (1678 [79%] in the empagliflozin group vs 1677 [78%] in the usual care group; rate ratio 1·03 [95% CI 0·96-1·10]; p=0·44). Among those not on invasive mechanical ventilation at baseline, there was no evidence of a significant difference in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (338 [16%] of 2084 vs 371 [17%] of 2143; risk ratio 0·95 [95% CI 0·84-1·08]; p=0·44). Two serious adverse events believed to be related to empagliflozin were reported: both were ketosis without acidosis. INTERPRETATION: In adults hospitalised with COVID-19, empagliflozin was not associated with reductions in 28-day mortality, duration of hospital stay, or risk of progressing to invasive mechanical ventilation or death so is not indicated for the treatment of such patients unless there is an established indication due to a different condition such as diabetes. FUNDING: UK Research and Innovation (Medical Research Council) and National Institute of Health Research (MC_PC_19056), and Wellcome Trust (222406/Z/20/Z). TRANSLATIONS: For the Nepali, Hindi, Indonesian (Bahasa) and Vietnamese translations of the abstract see Supplementary Materials section.
The Lancet · 2023 · 128 citations
- Medicine
- Anesthesia
- Emergency medicine
BACKGROUND: Low-dose corticosteroids have been shown to reduce mortality for patients with COVID-19 requiring oxygen or ventilatory support (non-invasive mechanical ventilation, invasive mechanical ventilation, or extracorporeal membrane oxygenation). We evaluated the use of a higher dose of corticosteroids in this patient group. METHODS: This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing multiple possible treatments in patients hospitalised for COVID-19. Eligible and consenting adult patients with clinical evidence of hypoxia (ie, receiving oxygen or with oxygen saturation <92% on room air) were randomly allocated (1:1) to either usual care with higher dose corticosteroids (dexamethasone 20 mg once daily for 5 days followed by 10 mg dexamethasone once daily for 5 days or until discharge if sooner) or usual standard of care alone (which included dexamethasone 6 mg once daily for 10 days or until discharge if sooner). The primary outcome was 28-day mortality among all randomised participants. On May 11, 2022, the independent data monitoring committee recommended stopping recruitment of patients receiving no oxygen or simple oxygen only due to safety concerns. We report the results for these participants only. Recruitment of patients receiving ventilatory support is ongoing. The RECOVERY trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). FINDINGS: Between May 25, 2021, and May 13, 2022, 1272 patients with COVID-19 and hypoxia receiving no oxygen (eight [1%]) or simple oxygen only (1264 [99%]) were randomly allocated to receive usual care plus higher dose corticosteroids (659 patients) versus usual care alone (613 patients, of whom 87% received low-dose corticosteroids during the follow-up period). Of those randomly assigned, 745 (59%) were in Asia, 512 (40%) in the UK, and 15 (1%) in Africa. 248 (19%) had diabetes and 769 (60%) were male. Overall, 123 (19%) of 659 patients allocated to higher dose corticosteroids versus 75 (12%) of 613 patients allocated to usual care died within 28 days (rate ratio 1·59 [95% CI 1·20-2·10]; p=0·0012). There was also an excess of pneumonia reported to be due to non-COVID infection (64 cases [10%] vs 37 cases [6%]; absolute difference 3·7% [95% CI 0·7-6·6]) and an increase in hyperglycaemia requiring increased insulin dose (142 [22%] vs 87 [14%]; absolute difference 7·4% [95% CI 3·2-11·5]). INTERPRETATION: In patients hospitalised for COVID-19 with clinical hypoxia who required either no oxygen or simple oxygen only, higher dose corticosteroids significantly increased the risk of death compared with usual care, which included low-dose corticosteroids. The RECOVERY trial continues to assess the effects of higher dose corticosteroids in patients hospitalised with COVID-19 who require non-invasive ventilation, invasive mechanical ventilation, or extracorporeal membrane oxygenation. FUNDING: UK Research and Innovation (Medical Research Council), National Institute of Health and Care Research, and Wellcome Trust.
The Lancet · 2022 · 382 citations
- Medicine
- Internal medicine
- Pediatrics
BACKGROUND: Casirivimab and imdevimab are non-competing monoclonal antibodies that bind to two different sites on the receptor binding domain of the SARS-CoV-2 spike glycoprotein, blocking viral entry into host cells. We aimed to evaluate the efficacy and safety of casirivimab and imdevimab administered in combination in patients admitted to hospital with COVID-19. METHODS: RECOVERY is a randomised, controlled, open-label platform trial comparing several possible treatments with usual care in patients admitted to hospital with COVID-19. 127 UK hospitals took part in the evaluation of casirivimab and imdevimab. Eligible participants were any patients aged at least 12 years admitted to hospital with clinically suspected or laboratory-confirmed SARS-CoV-2 infection. Participants were randomly assigned (1:1) to either usual standard of care alone or usual care plus casirivimab 4 g and imdevimab 4 g administered together in a single intravenous infusion. Investigators and data assessors were masked to analyses of the outcome data during the trial. The primary outcome was 28-day all-cause mortality assessed by intention to treat, first only in patients without detectable antibodies to SARS-CoV-2 infection at randomisation (ie, those who were seronegative) and then in the overall population. Safety was assessed in all participants who received casirivimab and imdevimab. The trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). FINDINGS: Between Sept 18, 2020, and May 22, 2021, 9785 patients enrolled in RECOVERY were eligible for casirivimab and imdevimab, of which 4839 were randomly assigned to casirivimab and imdevimab plus usual care and 4946 to usual care alone. 3153 (32%) of 9785 patients were seronegative, 5272 (54%) were seropositive, and 1360 (14%) had unknown baseline antibody status. 812 (8%) patients were known to have received at least one dose of a SARS-CoV-2 vaccine. In the primary efficacy population of seronegative patients, 396 (24%) of 1633 patients allocated to casirivimab and imdevimab versus 452 (30%) of 1520 patients allocated to usual care died within 28 days (rate ratio [RR] 0·79, 95% CI 0·69-0·91; p=0·0009). In an analysis of all randomly assigned patients (regardless of baseline antibody status), 943 (19%) of 4839 patients allocated to casirivimab and imdevimab versus 1029 (21%) of 4946 patients allocated to usual care died within 28 days (RR 0·94, 95% CI 0·86-1·02; p=0·14). The proportional effect of casirivimab and imdevimab on mortality differed significantly between seropositive and seronegative patients (p value for heterogeneity=0·002). There were no deaths attributed to the treatment, or meaningful between-group differences in the pre-specified safety outcomes of cause-specific mortality, cardiac arrhythmia, thrombosis, or major bleeding events. Serious adverse reactions reported in seven (<1%) participants were believed by the local investigator to be related to treatment with casirivimab and imdevimab. INTERPRETATION: In patients admitted to hospital with COVID-19, the monoclonal antibody combination of casirivimab and imdevimab reduced 28-day mortality in patients who were seronegative (and therefore had not mounted their own humoral immune response) at baseline but not in those who were seropositive at baseline. FUNDING: UK Research and Innovation (Medical Research Council) and National Institute of Health Research.
The Lancet · 2022 · 323 citations
- Medicine
- Internal medicine
BACKGROUND: We aimed to evaluate the use of baricitinib, a Janus kinase (JAK) 1-2 inhibitor, for the treatment of patients admitted to hospital with COVID-19. METHODS: This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple possible treatments in patients hospitalised with COVID-19 in the UK. Eligible and consenting patients were randomly allocated (1:1) to either usual standard of care alone (usual care group) or usual care plus baricitinib 4 mg once daily by mouth for 10 days or until discharge if sooner (baricitinib group). The primary outcome was 28-day mortality assessed in the intention-to-treat population. A meta-analysis was done, which included the results from the RECOVERY trial and all previous randomised controlled trials of baricitinib or other JAK inhibitor in patients hospitalised with COVID-19. The RECOVERY trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936) and is ongoing. FINDINGS: Between Feb 2 and Dec 29, 2021, from 10 852 enrolled, 8156 patients were randomly allocated to receive usual care plus baricitinib versus usual care alone. At randomisation, 95% of patients were receiving corticosteroids and 23% were receiving tocilizumab (with planned use within the next 24 h recorded for a further 9%). Overall, 514 (12%) of 4148 patients allocated to baricitinib versus 546 (14%) of 4008 patients allocated to usual care died within 28 days (age-adjusted rate ratio 0·87; 95% CI 0·77-0·99; p=0·028). This 13% proportional reduction in mortality was somewhat smaller than that seen in a meta-analysis of eight previous trials of a JAK inhibitor (involving 3732 patients and 425 deaths), in which allocation to a JAK inhibitor was associated with a 43% proportional reduction in mortality (rate ratio 0·57; 95% CI 0·45-0·72). Including the results from RECOVERY in an updated meta-analysis of all nine completed trials (involving 11 888 randomly assigned patients and 1485 deaths) allocation to baricitinib or another JAK inhibitor was associated with a 20% proportional reduction in mortality (rate ratio 0·80; 95% CI 0·72-0·89; p<0·0001). In RECOVERY, there was no significant excess in death or infection due to non-COVID-19 causes and no significant excess of thrombosis, or other safety outcomes. INTERPRETATION: In patients hospitalised with COVID-19, baricitinib significantly reduced the risk of death but the size of benefit was somewhat smaller than that suggested by previous trials. The total randomised evidence to date suggests that JAK inhibitors (chiefly baricitinib) reduce mortality in patients hospitalised for COVID-19 by about one-fifth. FUNDING: UK Research and Innovation (Medical Research Council) and National Institute of Health Research.
Effects of Antiplatelet Therapy After Stroke Caused by Intracerebral Hemorrhage
JAMA Neurology · 2021 · 48 citations
- Medicine
- Surgery
- Internal medicine
Importance: The Restart or Stop Antithrombotics Randomized Trial (RESTART) found that antiplatelet therapy appeared to be safe up to 5 years after intracerebral hemorrhage (ICH) that had occurred during antithrombotic (antiplatelet or anticoagulant) therapy. Objectives: To monitor adherence, increase duration of follow-up, and improve precision of estimates of the effects of antiplatelet therapy on recurrent ICH and major vascular events. Design, Setting and Participants: From May 22, 2013, through May 31, 2018, this prospective, open, blinded end point, parallel-group randomized clinical trial studied 537 participants at 122 hospitals in the UK. Participants were individuals 18 years or older who had taken antithrombotic therapy for the prevention of occlusive vascular disease when they developed ICH, discontinued antithrombotic therapy, and survived for 24 hours. After initial follow-up ended on November 30, 2018, annual follow-up was extended until November 30, 2020, for a median of 3.0 years (interquartile range [IQR], 2.0-5.0 years) for the trial cohort. Interventions: Computerized randomization that incorporated minimization allocated participants (1:1) to start or avoid antiplatelet therapy. Main Outcomes and Measures: Participants were followed up for the primary outcome (recurrent symptomatic ICH) and secondary outcomes (all major vascular events) for up to 7 years. Data from all randomized participants were analyzed using Cox proportional hazards regression, adjusted for minimization covariates. Results: A total of 537 patients (median age, 76.0 years; IQR, 69.0-82.0 years; 360 [67.0%] male; median time after ICH onset, 76.0 days; IQR, 29.0-146.0 days) were randomly allocated to start (n = 268) or avoid (n = 269 [1 withdrew]) antiplatelet therapy. The primary outcome of recurrent ICH affected 22 of 268 participants (8.2%) allocated to antiplatelet therapy compared with 25 of 268 participants (9.3%) allocated to avoid antiplatelet therapy (adjusted hazard ratio, 0.87; 95% CI, 0.49-1.55; P = .64). A major vascular event affected 72 participants (26.8%) allocated to antiplatelet therapy compared with 87 participants (32.5%) allocated to avoid antiplatelet therapy (hazard ratio, 0.79; 95% CI, 0.58-1.08; P = .14). Conclusions and Relevance: Among patients with ICH who had previously taken antithrombotic therapy, this study found no statistically significant effect of antiplatelet therapy on recurrent ICH or all major vascular events. These findings provide physicians with some reassurance about the use of antiplatelet therapy after ICH if indicated for secondary prevention of major vascular events. Trial Registration: isrctn.org Identifier: ISRCTN71907627.
The Lancet · 2021 · 561 citations
- Medicine
- Internal medicine
- Physical therapy
BACKGROUND: Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory actions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19. METHODS: In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospital with COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients were randomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once per day by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatment groups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment and were twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants and local study staff were not masked to the allocated treatment, but all others involved in the trial were masked to the outcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. FINDINGS: Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) were eligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was 65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomly allocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall, 561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days (rate ratio 0·97, 95% CI 0·87-1·07; p=0·50). No significant difference was seen in duration of hospital stay (median 10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days (rate ratio 1·04, 95% CI 0·98-1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, no significant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (risk ratio 0·95, 95% CI 0·87-1·03; p=0·24). INTERPRETATION: In patients admitted to hospital with COVID-19, azithromycin did not improve survival or other prespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restricted to patients in whom there is a clear antimicrobial indication. FUNDING: UK Research and Innovation (Medical Research Council) and National Institute of Health Research.
The Lancet · 2021 · 520 citations
- Medicine
- Internal medicine
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.
The Lancet · 2021 · 1078 citations
- Medicine
- Internal medicine
Frequent coauthors
- 1307 shared
Joanna M. Wardlaw
University of Edinburgh
- 1009 shared
Richard I. Lindley
University of Sydney
- 969 shared
Alessandro Adami
Ospedale Sacro Cuore Don Calabria
- 752 shared
Peter Sandercock
- 726 shared
André Peeters
UCLouvain
- 726 shared
Rüdiger von Kummer
Health and Education Research Management and Epidemiologic Services (United States)
- 515 shared
David J. Werring
University College London Hospitals NHS Foundation Trust
- 506 shared
Stefano Ricci
University of Washington
Education
- 1999
PhD, Medicine and Therapeutics
University of Glasgow
- 1989
MBChB, Medicine
University of Glasgow
- 1986
First Class BSc Honours, Cell Biology
University of Glasgow
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