Optimizing COVID-19 vaccine schedules for immunocompromised individuals

Bringing Optimised COVID-19 Vaccine Schedules To ImmunoCompromised Populations (BOOST-IC): an Adaptive Randomised Controlled Clinical Trial

PHASE3 · Bayside Health · NCT05556720

This study is testing whether giving extra doses of a COVID-19 vaccine helps people with weakened immune systems, like those with HIV or who have had organ transplants, to build better protection against the virus.

Quick facts

PhasePHASE3
Study typeInterventional
Enrollment960 (estimated)
Ages16 Years and up
SexAll
SponsorBayside Health (other gov)
Drugs / interventionsCAR T, chemotherapy, immunotherapy
Locations1 site (Melbourne, Victoria)
Trial IDNCT05556720 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates the safety and effectiveness of additional COVID-19 vaccine doses in immunocompromised individuals, including those with HIV, organ transplant recipients, and patients with certain blood cancers. Participants who have previously received 3 to 6 doses of approved COVID-19 vaccines will be randomly assigned to receive either one or two doses of a bivalent COVID-19 vaccine. The study aims to generate high-quality evidence on the immunogenicity of these booster strategies specifically for immunocompromised populations in Australia.

Who should consider this trial

Good fit: Ideal candidates include individuals aged 16 and older who are immunocompromised due to HIV, solid organ transplants, or specific hematological malignancies.

Not a fit: Patients who are contraindicated to receive a COVID-19 booster vaccination or who have not completed the required number of prior vaccine doses may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could enhance COVID-19 vaccine efficacy and safety for immunocompromised patients, potentially reducing their risk of severe illness.

How similar studies have performed: Other studies have explored COVID-19 vaccination in immunocompromised populations, but this trial aims to provide more targeted evidence on booster strategies, making it a novel approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Able to give informed consent and undertake study procedures
* Age ≥16 years old
* Have completed at least 3 months prior, 3- to 6-doses of an Australian TGA approved SARS-CoV-2 vaccine (including mRNA \[Pfizer or Moderna\], ChAdOx1 \[Oxford/Astra Zeneca\] or protein \[Novavax\])
* Fit the criteria to be included in one of the following 3 populations: Infected with HIV; Current recipient of a solid organ transplant including: kidney, pancreas, liver, malignancy episodes of severe rejection requiring T- or B-cell depleting agents in the prior 3 months; Undergoing chemotherapy, immunotherapy and/or targeted therapy, or completed in the last 2 years for: chronic lymphocytic leukemia, multiple myeloma or non-Hodgkin lymphoma.

Exclusion Criteria:

* Are contraindicated to receive a COVID-19 booster vaccination, e.g. history of anaphylaxis to a vaccine component or myocarditis attributed to previous receipt of an mRNA vaccine.
* Has had led less than 3 or more than 6 doses of COVID-19 vaccine
* Is on another clinical trial investigating alternate COVID-19 vaccination schedules or investigational drugs to prevent or treat COVID-19
* Life expectancy \< 12 months, or enrolment deemed not in the best interest of the patient
* Unable to provide informed consent
* Receipt of SARS-CoV-2 specific monoclonal antibodies in the 3 months prior to receiving the first dose of study vaccine
* Acute respiratory tract infection and/or temperature \> 38 degrees centigrade on day of receiving first dose of study vaccine
* History of autologous stem cell transplant in the prior 6 months or history of ever having an allogeneic stem cell transplant or CAR T-cell therapy

Where this trial is running

Melbourne, Victoria

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: HIV, Organ Transplantation, Lymphoma, Non-Hodgkin, Chronic Lymphocytic Leukemia, Multiple Myeloma, COVID-19 Vaccines

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.