What may be the first assessment of vaccination against respiratory syncytial virus (RSV) in individuals who are immunocompromised suggests that vaccination may be protective. Registration trials of RSV vaccines excluded people who were immunocompromised, leaving the protective effects of RSV vaccines in doubt for this population.
“RSV is a dangerous illness for those who are immunocompromised, and there is concern that these patients, especially patients after transplantation, don’t do well,” said Rachana Krishna, MBBS, MSCR, Assistant Professor of Medicine at the Medical University of South Carolina. “It is important to look at immune response in these individuals who are immunocompromised.”
The study, Antibody Response to Respiratory Syncytial Virus Vaccination in Immunocompromised Persons, provides the first evidence of heterogeneous response to RSV vaccines in an adult population that was largely self-reported as immunocompromised. People who are immunocompromised could include solid organ transplant recipients, patients on immunosuppressive drugs, and patients with rheumatoid arthritis, lupus, HIV, vasculitis, inflammatory arthritis, and/or Sjögren’s syndrome. About 80% of those in the study had undergone solid organ transplantation. Dr. Krishna noted that there were no individuals with bone marrow transplants in the study—another group at elevated risk for RSV.
A majority of patients who were immunocompromised in the study showed a 13- to 14-fold increase in antibody titers one month after vaccination with novel prefusion F-containing RSV vaccines. However, while the study suggested broad effectiveness against RSV, more than a third of the patients did not show seroconversion after vaccination.
“The drawback is this was not a vaccine efficacy study, so we don’t know whether the lack of a robust cellular response due to immunosuppression made a difference,” Dr. Krishna said. “Some patients can show T cell response even without seroconversion, so there may be efficacy there that we don’t know about. Studies that look at whether there is a decrease in infections and other outcomes like hospitalization and clinical outcomes would be more helpful in this population.”
The study may not provide the ideal efficacy outcomes, but the results are still useful, she said. Not having efficacy data for a population that is immunocompromised does not suggest there is a contraindication to vaccination or any other unusual concern. All the usual vaccination cautions apply to RSV vaccines in this population, including allergic reactions, injection site irritation, and Guillain-Barré syndrome. Clinicians can help patients understand that all vaccines carry risks regardless of the recipient’s immune status and that risks associated with vaccines are dramatically lower than risks associated with the infection that may come with forgoing vaccination.
“I would still recommend RSV vaccination for these [patients who are immunocompromised],” Dr. Krishna said. “However, the use in patients who are younger than 60 years is still unclear. These vaccines have been looked at in people who are older than 60, so the benefits in people who are younger than 60 and in different immunocompromised states is not totally clear. It is still a risk-benefit discussion with each patient.”