7555 Background: While CAR-T therapy is not myelo-ablative, patients with aggressive lymphoma treated with CD19 chimeric antigen receptor T cell therapy (CAR-T) are lymphodepleted and have prolonged B cell aplasia. The impact of CAR-T on immunologic protection from vaccine-preventable diseases (and thus the need to revaccinate) is not known. We report the vaccine titers of patients treated with axicabtagene ciloleucel (axi-cel) at Mayo Clinic. Methods: Retrospective chart review of adult lymphoma patients who received axi-cel from 9/2018 to 9/2020 for anti-viral and anti-bacterial titers prior to CAR-T infusion and at month 3 (MO3) post CAR-T. Results: Prior to CAR-T therapy, positive titer rate was highest for tetanus and lowest for Strep pneumoniae (Strep PNA) (Table). Similar trends were seen whether patients had stem cell transplant (ASCT) within 2 years of CAR-T (i.e. within immunization timeframe post ASCT) or not (Table). Compared to patients who had ASCT, those who did not had higher rate of positive titer for Strep PNA and lower rate for hepatitis B, Mumps, and VZV. The same trend for sero-positive rate were observed at MO3 post CAR-T. Patients with IgG<400 mg/dl received IVIG supplement for prophylaxis. Among the 23 patients who received IVIG, variable rate of conversion from negative to positive titers were seen for measles (1/2, 50%), mumps (2/3, 67%), rubella (2/3, 67%), varicella-zoster (VZV, 3/3, 100%), hepatitis A (6/6, 100%), hepatitis B (6/7, 86%) and Strep PNA (0/10, 0%). For patients who did not receive IVIG prophylaxis, there was one loss of seropositivity for Strep PNA (1/4, 25%). Conclusions: The presence of protective vaccine titers is variable for patients receiving CAR-T, regardless of recent ASCT. The loss of protective titers post CART was low. IVIG variably impacted vaccine titer status. Immunization remains important for patients with ASCT prior to CART, without completion of post ASCT immunization protocol. Further study is needed to inform the need for immunization and optimal timing post CART.[Table: see text]
The Impact of Granulocyte Colony Stimulating Factor on Patients Receiving Chimeric Antigen Receptor
T‐Cell
Therapy
