Use of COVID-19 vaccines in patients with liver disease and post-liver transplantation: Position statement of the Saudi association for the study of liver diseases and transplantation

Seroconversion and safety of Covid-19 vaccines in pa-tients with chronic liver disease and liver transplant: A systematic review

BACKGROUND AND AIMS

As part of the COVID-19 control strategy, a growing number of vaccine portfolios evolved and got fast-tracked through regulatory agencies, with a limited examination of their efficacy and safety in vulnerable populations, such as patients with chronic conditions and immunocompromised states. Patients with chronic liver disease (CLD), and cohorts post liver transplant (LT) in particular, were underrepresented in the determinant trials of vaccine development, hence the paucity of data on their efficacy and safety in published literature. This systematic review aims to examine the available evidence and ascertain the effectiveness and safety of Covid-19 vaccination in patients with CLD and those with LT.

METHODS

A systematic review of PubMed (Medline), Google Scholar, Cochrane Library, and ScienceDirect from inception until 1st March 2022 was conducted. We included observational studies and assessed vaccine efficacy regarding seroconversion or immunological rate, whereas serious or significant adverse effects have been considered safety outcomes when reported.

RESULTS

Studies comprised 45275 patients, performed in 11 different countries. Seroconversion or immunological rate after Covid-19 vaccination was mostly the primary endpoint, whereas other endpoints like covid-19 related adverse effects were also reported. Twenty-four of the final analyzed studies are prospective cohort studies, while four are retrospective cohort studies. Twenty-one studies included patients who underwent LT and received the Covid vaccine; nine included patients who had CLD due to various etiologies. The median age range of all included patients varied from 43-69 years. All patients with LT who received at least two doses of Covid vaccine had a seroconversion rate of around 60%. Patients with CLD had a seroconversion rate of about 92% post two doses of Covid vaccination. The average seroconversion rate in post-transplant recipients was around 45% after two doses of the significant Covid vaccines: Pfizer, AstraZeneca, Moderna, and Jansen. Only two studies have reported a higher seroconversion rate of 75% and 73% after the third dose of Covid vaccine. No significant adverse effects were reported in all studies; the most commonly reported negative effect was local injection site pain.

CONCLUSION

The present systematic review, comprising real-world observational data studies, concludes that Covid-19 vaccination was associated with 92% and 60% seroconversion rates in patients with CLD and LT, respectively. No significant side effects were reported in all studies. This finding helps to resolve the uncertainty associated with Covid-19 vaccination in this cohort of patients.

Research landscape on COVID-19 and liver dysfunction: A bibliometric analysis

BACKGROUND

The global spread of severe acute respiratory syndrome coronavirus 2, responsible for coronavirus disease 2019 (COVID-19), poses a significant risk to public health. Beyond the respiratory issues initially associated with the condition, severe cases of COVID-19 can also lead to complications in other organs, including the liver. Patients with severe COVID-19 may exhibit various clinical signs of liver dysfunction, ranging from minor elevations in liver enzymes without symptoms to more serious cases of impaired liver function. Liver damage is more commonly observed in patients with severe or critical forms of the disease.

AIM

To present the research landscape on COVID-19 and liver dysfunction while also offering valuable insights into the prominent areas of interest within this particular domain.

METHODS

On 18 February 2023, Scopus was utilised to conduct a comprehensive exploration of the relationship between COVID-19 and the liver dysfunction. The investigation encompassed the period from 1 January 2020 to 31 December 2022. Primary sources were meticulously examined and organised in a Microsoft Excel 2013 spreadsheet, categorised by journal, institution, funding agency, country and citation type. VOSviewer version 1.6.18 was employed to explore the prominent topics and knowledge network related to the subject.

RESULTS

There were 2336 publications on COVID-19 and liver dysfunction analysed in this study, of which 558 were published in 2020, 891 in 2021 and 887 in 2022. Researchers from 111 different countries participated in the retrieved documents. The United States contributed the most studies, with 497 documents, representing 21.28% of the total, followed by China with 393 documents (16.82%) and Italy with 255 documents (10.92%). In the context of research related to COVID-19 and the liver, co-occurrence analysis identified three distinct clusters of topics: (1) 'COVID-19 vaccines in liver transplant recipients'; (2) 'liver function tests as a predictor of the severity and clinical outcomes in hospitalised patients'; and (3) 'care of patients with liver disease during the COVID-19 pandemic'.

CONCLUSION

This bibliometric study provides a comprehensive overview of liver-related publications in COVID-19 research over the past 3 years. This study highlights the significant contributions of high-income nations, particularly the United States, China, and Italy, to the production of liver-related scholarly literature in this field. Most of the articles focused on liver dysfunction in patients with COVID-19 and the implications of the virus for gastroenterologists and hepatologists.

Safety and immunogenicity of inactivated COVID-19 vaccine CoronaVac and the RBD-dimer-based COVID-19 vaccine ZF2001 in chronic hepatitis B patients

Background and aims

Although COVID-19 vaccination is recommended for the patients with chronic liver disease, the clinical outcomes of COVID-19 vaccinated in patients with chronic hepatitis B (CHB) has not been well characterized. The study aimed to explore the safety and specific antibody responses following COVID-19 vaccination among CHB patients.

Methods

Patients with CHB were included. All patients were vaccinated with two doses of inactivated vaccine (CoronaVac) or three doses of adjuvanted protein subunit vaccine (ZF2001). The adverse events were recorded and neutralizing antibody (NAb) were determined 14 days following the whole-course vaccination.

Results

A total of 200 patients with CHB were included. Specific NAb against SARS-CoV-2 were positive in 170 (84.6%) patients. The median (IQR) concentrations of NAb were 16.32 (8.44-34.10) AU/ml. Comparison of immune responses between CoronaVac and ZF2001 vaccines showed no significant differences in neither the concentrations of NAb nor the seropositive rates (84.4 vs. 85.7%). Moreover, we observed lower immunogenicity in older patients and in patients with cirrhosis or underlying comorbidities. The incidences of adverse events were 37 (18.5%) with the most common adverse event as injection side pain [25 (12.5%)], followed by fatigue [15 (7.5%)]. There were no differences in the frequencies of adverse between CoronaVac and ZF2001 (19.3% vs. 17.6%). Almost all of the adverse reactions were mild and self-resolved within a few days after vaccination. Severe adverse events were not observed.

Conclusions

COVID-19 vaccines, CoronaVac and ZF2001 had a favorable safety profile and induced efficient immune response in patients with CHB.

Antibody Response and Safety of ChAdOx1-nCOV (Covishield) in Patients with Cirrhosis: A Cross-Sectional, Observational Study

INTRODUCTION

Patients with cirrhosis have a higher risk of severe COVID-19 and mortality and are high-priority patients for vaccination. However, cirrhotics were excluded from the phase 2/3 vaccine trials. Hence, we aimed to assess the antibody response and safety of Covishield (ChAdOx1nCoV-19) among patients with cirrhosis.

METHODS

Patients who attended the tele-hepatology services at our institute from March 2020 to June 2021 and diagnosed with cirrhosis as per their medical records were telephonically interviewed in July 2021 using a pre-specified questionnaire. Patients who had completed 2 doses of ChAdOx1-nCOV (with the 2^nd dose administered at least 2 weeks back) and without history of documented COVID-19 infection (pre- or post-vaccination) were tested for antibodies against the spike protein. Seropositive patients were divided into high, moderate, and low antibody responses based on the signal/cut-off.

RESULTS

We interviewed 784 patients with cirrhosis. At least 1 dose of ChAdOx1-nCOV was received by 231 patients among whom 134 (58%) had received 2 doses. Documented COVID-19 was reported in 3.9% patients who received at least 1 dose of ChAdOx1-nCOV including breakthrough infections in 3.7% patients vaccinated with 2 doses. Local and systemic adverse events were reported by 42% and 22.1% patients. None developed anaphylaxis, acute decompensation, acute-on-chronic liver failure, or other serious adverse events requiring hospitalization. Seroconversion was documented in 81 (92%) out of 88 patients. No difference was observed in level of antibody response between patients with compensated and decompensated cirrhosis (p = 0.12).

CONCLUSION

Our preliminary data suggest that ChAdOx1-nCOV is safe with high seroconversion rates in patients with cirrhosis.

COVID-19 Vaccines for Adults and Children with Autoimmune Gut or Liver Disease

The SARS-CoV-2 pandemic raised many challenges for all patients with chronic conditions and those with autoimmune diseases, both adults and children. Special attention is paid to their immunological status, concomitant diseases, and the need for immunosuppressive therapy. All of these factors may impact their COVID-19 course and outcome. COVID-19 vaccination is accepted as one of the most successful strategies for pandemic control. However, individuals with immune-mediated chronic diseases, including autoimmune liver and gut diseases, have been excluded from the vaccine clinical trials. Therefore, we rely on real-world data from vaccination after vaccine approval for these patients to fill the evidence gap for the long-term safety and efficacy of COVID-19 vaccines in patients with autoimmune gut and liver diseases. Current recommendations from inflammatory bowel disease (IBD) societies suggest COVID-19 vaccination in children older than 5 years old, adults and even pregnant females with IBD. The same recommendations are applied to patients with autoimmune liver diseases. Nevertheless, autoimmune disease patients still experience high levels of COVID-19 vaccine hesitancy, and more studies have to be conducted to clarify this issue.