Improved Vaccine Responses in Patients with Hematological Malignancies After Chimeric Antigen Receptor (CAR) T-cell Therapy

Strategic Insights -

A recent study published in the Blood Cancer Journal has shed light on the importance of immune reconstitution in vaccine responses post-CAR T therapy for patients with hematological malignancies. Researchers at Memorial Sloan-Kettering Cancer Center conducted a single-center, retrospective study analyzing vaccine responses in 73 patients who received post-CAR T therapy vaccination between 2018 and 2024. The study found that seroprotection rates were high for tetanus and poliovirus, but lower for other vaccine-preventable infections. The research also highlighted the importance of pre-vaccination IgA levels and absolute B-cell counts in determining vaccine responses.

Key Takeaways:

  • The study analyzed vaccine responses in 73 patients who received post-CAR T therapy vaccination between 2018 and 2024.
  • Seroprotection rates were high for tetanus (85%) and poliovirus (85%), but lower for other vaccine-preventable infections.
  • CD19 CAR T recipients had higher pre-vaccination seroprotection rates than BCMA recipients, but vaccine responses did not differ significantly between groups.
  • Pre-vaccination IgA levels were significantly associated with vaccine response, and absolute B-cell counts trended higher among responders (p = 0.054).
  • The research concluded that immune reconstitution is crucial for vaccine responses post-CAR T therapy.
  • The study was funded by the National Institutes of Health (NIH), NIH/NCI Cancer Center Support Grant, and other organizations.

Statistics:

  • 73 patients were included in the study.
  • 49 patients had pre- and post-vaccination titers available.
  • Seroprotection rates were:

+ 85% for tetanus

+ 85% for poliovirus

+ 100% for tetanus among patients not seroprotected prior to vaccination

+ 75% for diphtheria

+ 62% for haemophilus influenzae type b

+ 48% for pertussis

+ 43% for hepatitis A

+ 44% for hepatitis B

+ 33% for pneumococcal disease

  • Pre-vaccination IgA levels were significantly associated with vaccine response.

Sources:

  • Blood Cancer Journal, 2025; 15(1)
  • NewsRx LLC. New Vaccination Study Findings Have Been Reported from Memorial Sloan-Kettering Cancer Center (Humoral Vaccine Responses Following Chimeric Antigen Receptor T-cell Therapy for Hematological Malignancies). Vaccine Weekly. July 30, 2025; p 270.