Effect of SARS-CoV-2 Vaccination in Liver Transplant Recipients

Study Overview
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Brief Summary
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To investigate the variations in the humoral response to vaccines for the prevention of COVID-19 in liver transplant patients based on the type of immunosuppressive therapy adopted (tacrolimus based vs no-tacrolimus based) and immunosuppressive blood levels.

Official Title
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Evaluation of SARS-CoV-2 Antibody Response After Vaccination in Liver Transplant Recipients Who Undergo Tailored Immunosuppression Therapy

Conditions
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SARS-CoV-2 Vaccination, Liver Transplantation

Intervention / Treatment
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* Diagnostic Test: Immunoassay, by ECLIA, for the quantitative in vitro determination of antibodies (including IgG) to the SARS - CoV - 2 spike protein (S) anti-RBD (receptor-binding domain) in serum and plasma samples.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Liver transplanted patients >18 years of age. Patients who underwent liver transplantation between 01/2015 to 12/2021. Patients who underwent liver transplantation at Policlinico Tor Vergata, Rome, Italy. Patients who have had three doses of a vaccine for the prevention of COVID-19. Patients who have had three doses of a SARS-CoV-2 vaccine and who have contracted SARS-CoV-2 infection. Exclusion Criteria: Patients who have more or less than three dose of a vaccine for the prevention of COVID-19 Patients not vaccinated for prevention of SARS-CoV-2 infection. Patients who have had three doses of a vaccine for the prevention of COVID-19 prior to liver transplantation.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| tacrolimus-based immunosuppresion<br>The TAC-based group will include any patient on tacrolimus monotherapy and patients taking multiple IS medications with blood tacrolimus levels > 5 ng/mL | Diagnostic Test: Immunoassay, by ECLIA, for the quantitative in vitro determination of antibodies (including IgG) to the SARS - CoV - 2 spike protein (S) anti-RBD (receptor-binding domain) in serum and plasma samples.<br>* Blood test to value the antibody response to vaccination<br>|
| NON-tacrolimus-based immunosuppresion<br>The NON-TAC-based group will include any patient on TAC-free therapy and patient taking multiple IS medications with blood tacrolimus levels < 5 ng/mL | Diagnostic Test: Immunoassay, by ECLIA, for the quantitative in vitro determination of antibodies (including IgG) to the SARS - CoV - 2 spike protein (S) anti-RBD (receptor-binding domain) in serum and plasma samples.<br>* Blood test to value the antibody response to vaccination<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of positive antibody titer | > 0.8 U/mL | Between 30 and 120 ± 15 days after the completion of the vaccination cycle | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of highly protective antibody titer | >100 BAU/mL | Between 30 and 120 ± 15 days after the completion of the vaccination cycle | 
| Median antibody titer absolute value | BAU/mL | Between 30 and 120 ± 15 days after the completion of the vaccination cycle |