Examining the Immunological Effects of COVID-19 Vaccination in Patients with Conditions Potentially Leading to Diminished Immune Response Capacity – The OCTAVE Trial (preprint)

SARS-COV-2 vaccines have been shown to be efficacious primarily in healthy volunteer populations and population level studies. Immune responses following SARS-CoV-2 vaccination are less well characterised in potentially immune vulnerable patient groups, including those with immune-mediated inflammatory and chronic diseases (inflammatory arthritis [IA] incorporating rheumatoid arthritis [RA] and psoriatic arthritis [PsA]; ANCA-Associated Vasculitis [AAV]; inflammatory bowel disease [IBD]); hepatic disease (HepD), end stage kidney disease requiring haemodialysis (HD) without or with immunosuppression (HDIS); solid cancers (SC) and haematological malignancies (HM), and those that have undergone haemopoietic stem cell transplant (HSCT). The OCTAVE trial is a multi-centre, multi-disease, prospective cohort that will comprehensively assess SARS-CoV-2 vaccine responses within and between the abovementioned disease cohorts using common analytical platforms in patients recruited across the United Kingdom (UK). The majority of subjects received either COVID-19 mRNA Vaccine BNT162b2 (Pfizer/BioNTech) or ChAdOx1 Vaccine (AstraZeneca formerly AZD1222) as part of the UK National COVID19 vaccination programme. As of 13 th August 2021; 2,583 patients have been recruited. We report herein the humoral and T cell immune response results from the first 600 participants recruited where serology data are available at baseline, pre-second vaccine dose (boost) and/or 4 weeks post second dose. We also include in the analysis, data obtained from 231 healthy individuals from the PITCH (Protective Immunity from T cells in Healthcare workers) study. Overall, in comparison to PITCH where 100% of tested individuals (n=93) generated anti-Spike antibodies after vaccine doses, 89% of patients within OCTAVE seroconverted 4 weeks after second vaccine dose. By corollary, approximately 11% of patients across all disease cohorts fail to generate antibodies that react to SARS-CoV-2 spike 4 weeks after two vaccines. Failure to generate spike reactive antibodies was found at a higher proportion in some specific patient subgroups, particularly AAV (72.4%), HD-IS (16.7%) and HepD (16.7%). Importantly, all recruited AAV patients had received Rituximab; a targeted B cell depletion therapy. Furthermore, even in those who seroconverted, 40% of patients across disease cohorts generate lower levels of SARS-CoV-2 antibody reactivity compared to healthy subjects after two SARS-CoV-2 vaccines; the functional significance of these findings in providing protection from subsequent SARS-CoV-2 exposure is not currently known. In contrast to the observed serological response, evaluation of the Spike-specific T cell response revealed that across all patient sub-groups (including AAV) a response similar to healthy individuals was generated. Our data argue strongly for further vaccination strategies to optimise humoral immune responses against SARS-CoV-2 in patients with chronic diseases and/or patients on immune suppressive therapies. Trial Registration: The trial is registered on ISRCTN 12821688.Funding: This work was supported by the Medical Research Council COVID-19 Immunity – National Core Study (IMM-NCS) [grant number MC-PC-20031]. Staff at the Cancer Research UK Clinical Trials Unit (CRCTU) are supported by a core funding grant from Cancer Research UK (C22436/A25354). PK and EB are supported by the NIHR Birmingham Biomedical Research Centres at the University Hospitals Birmingham NHS Foundation Trust and the University of Birmingham Biomedical Research Centres. EB and PK are supported by an NIHR Senior Investigator award. PK is funded by WT109965MA. SJD is funded by an NIHR Global Research Professorship (NIHR300791). TdS is funded by a Wellcome Trust Intermediate Clinical Fellowship (110058/Z/15/Z). DS is supported by the NIHR Academic Clinical Lecturer programme in Oxford. LT is supported by the Wellcome Trust (grant number 205228/Z/16/Z), the U.S. Food and Drug Administration Medical Countermeasures Initiative contract 75F40120C00085. and the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Emerging and Zoonotic Infections (NIHR200907) at University of Liverpool in partnership with Public Health England (PHE), in collaboration with Liverpool School of Tropical Medicine and the University of Oxford. The PITCH (Protective Immunity from T cells to Covid-19 in Health workers) Consortium, is funded by the UK Department of Health and Social Care with contributions from UKRI/NIHR through the UK Coronavirus Immunology Consortium (UKCIC), the Huo Family Foundation and The National Institute for Health Research (UKRIDHSC COVID-19 Rapid Response Rolling Call, Grant Reference Number COV19-RECPLAS).Declaration of Interest: None to declare. Ethical Approval: This study was approved by the UK Medicines and Healthcare Products Regulatory Agency on the 5th February 2021 and the London and Chelsea Research Ethics Committee (REC Ref:21/HRA/0489) on 12th February 2021, with subsequent amendments approved on 3rd March 2021, 19th April 2021 and 26th April 2021).

FXR inhibition reduces ACE2 expression, SARS-CoV-2 infection and may improve COVID-19 outcome (preprint)

Prevention of SARS-CoV-2 entry in cells through the modulation of viral host receptors, such as ACE2, could represent a new therapeutic approach complementing vaccination. However, the mechanisms controlling ACE2 expression remain elusive. Here, we identify the farnesoid X receptor (FXR) as a direct regulator of ACE2 transcription in multiple COVID19-affected tissues, including the gastrointestinal and respiratory systems. We demonstrate that FXR antagonists, including the over-the-counter compound z-guggulsterone (ZGG) and the off-patent drug ursodeoxycholic acid (UDCA), downregulate ACE2 levels, and reduce susceptibility to SARS-CoV-2 infection in lung, cholangiocyte and gut organoids. We then show that therapeutic levels of UDCA downregulate ACE2 in human organs perfused ex situ and reduce SARS-CoV-2 infection ex vivo. Finally, we perform a retrospective study using registry data and identify a correlation between UDCA treatment and positive clinical outcomes following SARS-CoV-2 infection, including hospitalisation, ICU admission and death. In conclusion, we identify a novel function of FXR in controlling ACE2 expression and provide evidence that this approach could be beneficial for reducing SARS-CoV-2 infection, thereby paving the road for future clinical trials.

Longitudinal analysis of the utility of liver biochemistry in hospitalised COVID-19 patients as prognostic markers (preprint)

Background: COVID-19, the clinical syndrome caused by infection with SARS-CoV-2, has been associated with deranged liver biochemistry in studies from China, Italy and the USA. However, the clinical utility of liver biochemistry as a prognostic marker of outcome for COVID-19 is currently debated. Methods: We extracted routinely collected clinical data from a large teaching hospital in the UK, matching 585 hospitalised SARS-CoV-2 RT-PCR-positive patients to 1165 hospitalised SARS-CoV-2 RT-PCR-negative patients for age, gender, ethnicity and pre-existing comorbidities. Liver biochemistry was compared between groups over time to determine whether derangement was associated with outcome. Results: 26.8% (157/585) of COVID-19 patients died, compared to 11.9% (139/1165) in the non-COVID-19 group (p<0.001). At presentation, a significantly higher proportion of the COVID-19 group had elevated alanine aminotransferase (20.7% vs. 14.6%, p=0.004) and hypoalbuminaemia (58.7% vs. 35.0%, p<0.001), compared to the non-COVID-19 group. Within the COVID-19 group, those with hypoalbuminaemia at presentation had 1.83-fold increased hazards of death compared to those with normal albumin (adjusted hazard ratio [HR] 1.83, 95% CI 1.25-2.67), whilst the hazard of death was ~4-fold higher in those aged [≥]75 years (adjusted HR 3.96, 95% CI 2.59-6.04) and ~3-fold higher in those with pre-existing liver disease (adjusted HR 3.37, 95% CI 1.58-7.16). In the COVID-19 group, alkaline phosphatase increased (R=0.192, p<0.0001) and albumin declined (R=-0.123, p=0.0004) over time in patients who died. We did not find a significant association between other liver biochemistry and death. Conclusion: In this UK population, liver biochemistry is commonly deranged in patients with COVID-19 but only baseline low albumin and a rising alkaline phosphatase over time are prognostic markers for death.