Immune Response to Third Dose of COVID-19 Vaccine in Solid Organ Transplant

Pontificia Universidad Catolica de Chile

Status: Completed

Conditions: COVID-19; Vaccine Response Impaired; SARS-CoV-2 Infection; Solid Organ Transplant

Treatments: Biological: Three doses of SARS-CoV-2 BNT162b2 vaccine (observational); Biological: Two doses of CoronaVac and one dose of BNT162b2 SARS-CoV-2 vaccine (observational)

Study type: Observational

Funder types: Other

Identifiers

NCT05124509

210405014E

Details and patient eligibility

About

The Coronavirus Disease 2019 (COVID-19) pandemic has claimed over 5 million lives globally. Fortunately, a substantial and growing number of SARS-CoV-2 vaccines with very high efficacy have been developed, manufactured, and rapidly approved. Novel mRNA vaccines such as the BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) have reported a stunning >94% efficacy against COVID-19. However, global access has not been equitable, with many low- and middle-income countries having no vaccine access or access under emergency use mainly to traditional inactivated SARS-CoV2-2 vaccines such as BBIBP-CorV (Sinopharm Beijing), CoronaVac (Sinovac) and BBV152 (Bharat Biotech). Emerging studies have shown that lower concentrations of neutralizing antibodies (Nab) are attained after CoronaVac than after an mRNA-based vaccine in healthy individuals. This difference seems to be more pronounced in immunocompromised patients who are at higher risk of severe COVID-19 and death from COVID-19. As such, several countries including the United States, Israel and Chile have recommended a third vaccine dose for high-risk populations. However, it is not currently known which is the best vaccine combination regarding immunogenicity, particularly in these vulnerable patients.

This observational study will explore the humoral and cellular response to a SARS-CoV-2 BNT162b2 vaccine booster in solid organ transplant patients who received two previous doses of the inactivated Coronavac or two doses of BNT162b2 vaccines.

Enrollment: 147 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Solid organ transplant patients in the last 10 years and currently under immunosuppressive therapy
• Vaccination with two doses of Coronavac vaccine or BNT162b2 vaccines, followed by a booster dose (3d dose) of BNT162b2 vaccine administered in the previous 8-12 weeks.

Exclusion criteria

• Previous SARS-CoV-2 infection
• Booster vaccine (3rd dose) administered less than 8 weeks or more than 12 weeks before enrolment
• Intravenous immunoglobulin therapy 60 days before enrolment
• Previous SARS-CoV-2 vaccine different from CoronaVac or BNT162b2

Trial design

147 participants in 2 patient groups

Three doses of BNT162b2 vaccine

Description:

Solid organ transplant patients who received three doses of BNT162b2

Treatment:

Biological: Three doses of SARS-CoV-2 BNT162b2 vaccine (observational)

Two doses of Coronavac and one of BNT162b2 vaccine

Description:

Solid organ transplant patients who received two doses of CoronaVac and one dose of BNT162b2

Treatment:

Biological: Two doses of CoronaVac and one dose of BNT162b2 SARS-CoV-2 vaccine (observational)