Immunosuppression and COVID-19 Boosters

Summary

It is important people receiving immunosuppressive therapy are provided with the best protection against COVID-19 because they are at greater risk of severe illness should they become infected. As severe immunosuppression can reduce the efficacy of COVID-19 vaccination, doctors agree that COVID-19 boosters is are important to maximise the vaccine response in these people. However, we don't currently know the best time to give booster vaccines to people about to start immunosuppressive therapy. This research aims to address this knowledge gap by examining whether the greatest protection is provided by giving the COVID-19 booster just before the immunosuppressive therapy starts or by waiting and giving the booster 6 months after treatment start. At the 6-month timepoint, in many cases the more intensive immunosuppression is often weaning and the immune system is starting to rebuild.

Timeline

Start

2023-07-21

Primary completion

2026-12-31

Completion

2026-12-31

Publications

• Carey DL, Ahlenstiel G, Brilot F, Brown DA, Bull R, Crowther H, Cunningham A, Davenport MP, Diamond P, Hamad N, Johnston A, Kelleher AD, Lee FJ, Matthews GV, Petoumenos K, Quichua GC, Swaminathan S, Trotman J, Turville S, Vukic S, Wong P, Sasson SC. Comparison of immunity-boosting regimens for COVID-19 upon initiation of immunosuppressive therapy (CIRCUIT): study protocol for a randomised, controlled clinical trial. BMJ Open. 2026 Apr 24;16(4):e115259. doi: 10.1136/bmjopen-2025-115259.
• Zorger AM, Hirsch C, Baumann M, Feldmann M, Brockelmann PJ, Mellinghoff S, Monsef I, Skoetz N, Kreuzberger N. Vaccines for preventing infections in adults with haematological malignancies. Cochrane Database Syst Rev. 2025 May 21;5(5):CD015530. doi: 10.1002/14651858.CD015530.pub2.

Drugs

Indications