Tundra Space

Tundra Space

Clinical Research Directory

Browse clinical research sites, groups, and studies.

5 clinical studies listed.

Filters:

Vaccine Response Impaired

Tundra lists 5 Vaccine Response Impaired clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.

This data is also available as a public JSON API. AI systems and LLMs are encouraged to use it for structured queries.

RECRUITING

NCT06262776

Safety and Immunogenicity of Recombinant Zoster Vaccine for Transplant Recipients

The goal of this clinical trial is to compare responses to Varicella Zoster vaccination between transplant patients on different medication regimens, and their healthy co-habitants. The main questions it aims to answer are: 1. Are there differences in vaccination immunological responses in transplant patients on different immunosuppression regimens? 2. Are there differences in vaccination immunological responses between transplant patients and their healthy co-habitants? Participants will all receive a 2-dose course of SHINGRIX recombinant Zoster vaccination, and have immunological responses measured and compared at 5 timepoints between 1 week to 1 year post-vaccination.

Gender: All

Ages: 18 Years - Any

Updated: 2026-04-09

1 state

Immunosuppression
Vaccine Response Impaired
ACTIVE NOT RECRUITING

NCT05060991

Impact of Immunosuppression Adjustment on COVID-19 Vaccination Response in Kidney Transplant Recipients

Immunocompromised individuals, such as solid organ transplant (SOT) recipients are at high risk of COVID-19 associated complications and mortality. Retrospective studies so far have shown that a majority of SOT recipients did not develop appreciable anti-spike antibody response after a first, second, or even third dose of mRNA vaccine. Treatment with antimetabolites was associated with poor vaccine response. The goal of this study is 1) examine whether transient immunosuppression reduction improves the immune response to a third dose of SARS-CoV-2 mRNA vaccine in kidney transplant recipients and 2) to assess the safety of immunosuppression reduction before and after third dose SARS-CoV-2 mRNA vaccination.

Gender: All

Ages: 18 Years - Any

Updated: 2026-04-03

1 state

COVID-19
Immunosuppression
Vaccine Response Impaired
RECRUITING

NCT05923970

Is a Third Dose of MMRV Vaccine Beneficial for the Adult Population in Alberta?

The current recommendation for a full course of measles-mumps-rubella-(varicella) vaccine (MMR(V)) is two doses. The problem is, many individuals within the vaccinated cohort show antibody levels that are below the level considered to be protective, even after two doses of vaccine. Because of these waning antibody levels, it is currently unknown whether highly vaccinated populations are protected from infection against measles, mumps, rubella, or varicella should they be exposed to any of these viruses. The uncertainty of a woman's immune status is partly due to the type of testing that is used to indicate protection. While immunity to viral infection requires both a humoral and a cell mediated immune (CMI) response, only humoral (antibody) responses are measured routinely in the laboratory. This study will examine CMI responses and the role of a third dose of vaccine for previously vaccinated women whose antibody levels are below the cut off. This study will not administer vaccine, but rather will include women who have received a third dose of vaccination through routine health care follow up in the study cohort.

Gender: FEMALE

Ages: 18 Years - Any

Updated: 2026-03-16

1 state

Vaccination Failure
Vaccine Response Impaired
RECRUITING

NCT06148025

Antibiotics and Vaccine Immune Responses Study

The goal of this clinical trial is to examine immune responses to the BCG vaccine in healthy adults who have, or who have not, taken antibiotics to deplete their gut bacteria prior to vaccination. The main question it aims to answer is: does depletion of the gut microbiota lead to impaired BCG-induced protection against specific and non-specific to challenges to the immune system?

Gender: All

Ages: 18 Years - 35 Years

Updated: 2025-12-10

1 state

Vaccine Response Impaired
RECRUITING

NCT06593210

RSV Vaccine in Transplant Recipients

Adjuvant, non-live RSV vaccine will be administered to adult lung and allogeneic hematopoietic stem cell transplant recipients. The safety and immunogenicity of this intervention will be studied. Blood work will be collected before and after the intervention, to assess humoral and cellular immunity. Participants will be followed for adverse reaction, hospitalization, RSV breakthrough infection, graft rejection or graft versus host disease. This study has Health Canada and UHN REB approval.

Gender: All

Ages: 18 Years - Any

Updated: 2025-11-26

Vaccine Response Impaired
Respiratory Syncytial Virus Infections
Immune Suppression