Homologous vs Heterologous Third Vaccination in Kidney Transplant Recipients Kidney Transplant Recipients

Study Overview
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Brief Summary
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Randomized-controlled trial comparing homologous (mRNA vaccine) vs. heterologous (vector vaccine) for third SARS-CoV-2 vaccine dose in kidney transplant recipients not responding to initial prime-boost vaccination with an mRNA vaccine.

Official Title
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Single Blinded Randomized Controlled Trial on BNT162b2 or mRNA-1273 (mRNA) vs Ad26COVS1 or ChAdOx1-S (Viral Vector) for Third Vaccination in Kidney Transplant Recipients Without SARS-CoV-2 Spike Protein Antibodies Following Full Vaccination

Conditions
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COVID-19

Intervention / Treatment
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* Drug: Ad26COVS1
* Drug: ChAdOx1 SARS2 Vaccine
* Drug: BNT162B2
* Drug: mRNA-1273


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patient has received a kidney transplantation full SARS-CoV-2 vaccination with mRNA vaccine (two doses) at least 4 weeks before screening > 18 years of age no SARS-CoV-2 spike protein antibodies at least 4 weeks after the second dose of an mRNA vaccine Exclusion Criteria: acute illness with fever Prior documented infection with SARS-CoV-2 triple anticoagulation therapy Subject is currently enrolled in or has not yet completed at least 30 days since ending other investigational device or drug trial(s), or subject is receiving other investigational agent(s) Subject has known sensitivity or intolerance to any of the products to be administered for the purpose of this study Subject has any kind of disorder that compromises the ability of the subject to give written informed consent and/or to comply with the study procedures Subject is pregnant or breast feeding

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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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: homologous 3rd vaccination (mRNA vaccine)<br>Participants will receive a third SARS-CoV-2 vaccination with the same mRNA vaccine they received for the initial prime-boost vaccination (BNT162b2 or mRNA-1273 ) | Drug: BNT162B2<br>* Homologous vaccination<br>Drug: mRNA-1273<br>* Homologous vaccination<br>|
| Experimental: heterologous 3rd vaccination (vector vaccine)<br>participants will receive a third SARS-CoV-2 vaccination with a vector vaccine (Ad26COVS1 or ChAdOx1-S) | Drug: Ad26COVS1<br>* Heterologous vaccination<br>Drug: ChAdOx1 SARS2 Vaccine<br>* Heterologous vaccination<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seroconversion at 4 weeks | number of patients developing SARS-CoV-2 antibodies at 4 weeks after 3rd vaccination | 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seroconversion at 12 weeks | number of patients developing SARS-CoV-2 antibodies at 12 weeks after 3rd vaccination (> 0.8 BAU/mL) | 3 months | 
| SARS-CoV-2 antibody levels at 4 weeks | SARS-CoV-2 antibody levels at 4 weeks after the third vaccination | 4 weeks | 
| SARS-CoV-2 antibody levels at 12 weeks | SARS-CoV-2 antibody levels at 12 weeks after the third vaccination | 3 months | 
| Seroconversion at 36 weeks | number of patients developing SARS-CoV-2 antibodies at 36 weeks after 3rd vaccination (> 0.8 BAU/mL) | 6 months |