Clinical trial NCT05124509: Immune Response to Third Dose of COVID-19 Vaccine in Solid Organ Transplant
Official title: Immune Response to Third Dose of SARS-CoV-2 Vaccine in a Cohort of Solid Organ Transplant Recipients
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: COVID-19
SARS-CoV-2 Infection
Solid Organ Transplant
Vaccine Response Impaired
Lead sponsor: Pontificia Universidad Catolica de Chile
Sponsor class: OTHER
First posted: 2021-11-18
Enrollment: 147
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Solid organ transplant patients in the last 10 years and currently under immunosuppressive therapy

Brief summary: 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.


Eligibility criteria: 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

Primary outcomes:
measure: IgG seropositivity 8-12 weeks after third dose BNT162b2 (booster) vaccine.
timeFrame: 8-12 weeks after booster vaccine
Secondary outcomes:
measure: Proportion of positive neutralizing antibodies 8 to 12 weeks after third dose BNT162b2 (booster) vaccine.
timeFrame: 8-12 weeks after booster vaccine
measure: Neutralizing geometric mean titers 8 to 12 weeks after third dose of BNT162b2 (booster) vaccine.
timeFrame: 8-12 weeks after booster vaccine
Other outcomes:
measure: The number of IFN-y-spot forming T cells SARS-CoV-2 specific after third dose of BNT162b2 (booster) vaccine.
timeFrame: 8-12 weeks after booster vaccine
Locations:
city: Santiago
country: Chile
facility: Pontificia Universidad Católica de Chile
Study officials:
References:
citation: Dib M, Le Corre N, Ortiz C, Garcia D, Ferres M, Martinez-Valdebenito C, Ruiz-Tagle C, Ojeda MJ, Espinoza MA, Jara A, Arab JP, Rabagliati R, Vizcaya C, Ceballos ME, Sarmiento M, Mondaca S, Vinuela M, Pastore A, Szwarcfiter V, Galdames E, Barrera A, Castro P, Galvez NM, Soto JA, Bueno SM, Kalergis AM, Nervi B, Balcells ME. SARS-CoV-2 vaccine booster in solid organ transplant recipients previously immunised with inactivated versus mRNA vaccines: A prospective cohort study. Lancet Reg Health Am. 2022 Dec;16:100371. doi: 10.1016/j.lana.2022.100371. Epub 2022 Sep 23.