Community oncologists' and patients' perspectives on the post-CAR-T care transition: A convergent mixed-methods study.

e23134 Background: Chimeric antigen receptor T-cell (CAR-T) therapy is administered at accredited centers, with (w/) patients (pts) usually transitioning back to their community oncologist (CO) 30 days post-treatment or after acute toxicities resolve. This study explores the challenges faced during this period, from both CO and patient perspectives. Methods: A convergent mixed methods study was conducted between (b/w) March-April 2024. Quantitative aim assessed challenges faced by COs who referred at least 1 pt to Stephenson Cancer Center (SCC) (CAR-T Center) for CAR-T therapy (2019-2024). Online survey w/ hypothetical vignettes were used. COs ranked difficulty of various pt care aspects on a Likert scale from 1 (least) to 5 (most) challenging. Descriptive statistics summarized key challenges. Qualitative aim explored pt challenges. Eligible participants were over 18, referred to SCC, and at least 6 months post-CAR T. Zoom interviews were conducted and assessed for themes. Results: 33/79 (42%) COs completed the survey, w/ 88% from Oklahoma and 12% from neighboring states. 20 pts were interviewed, w/ a mean time of 21 months post-CAR-T therapy. Among responding COs, 79% referred 1-5 pts, 12% referred 6-10, 3% referred > 10 and 6.1% preferred not to answer. Of those referred, 70% reported at least one pt underwent CAR-T therapy. Quantitative and qualitative results were analyzed and integrated using a joint display (Table 1). Regarding post-CAR-T immunization, 82% agreed SCC should set the schedule. 44% viewed SCC as the primary site for administration. The survey inquired about potential steps to cope with challenges during the transition period. COs suggested that a 'Best Practices' handbook (91%) and a CAR-T aftercare webinar (64%) would be helpful. Patients suggested a post-CAR-T therapy timeline and support for immune system optimization. Conclusions: Further research is needed to better understand the pts’ and COs’ experience during the transition period. Implementing resources like a 'Best Practices' handbook, webinar series, and patient education is essential. Convergent mixed-methods analysis - COs' and Pts' perspectives on the Post-CAR-T care. Themes Quantitative Results- Challenges faced by COs (%- Likert Scale) Qualitative Results- Challenges faced by Pts Defining care responsibilities b/w SCC and COs 5: 41 4: 16 3: 22 2: 12 1: 9 Pts were unsure whom to contact (SCC or COs) and were confused by inconsistent guidance Management of RD (relapse disease) 5: 38 4: 28 3: 28 2: 3 1: 3 5 pts were anxious about RD. Others accepted the risk as manageable Communication of events with SCC in post-CAR-T period 5: 13.3 4: 24 3: 13.3 2: 13.3 1: 37 Pts noted occasional communication gaps b/w the SCC and COs but most felt it didn’t impact care Knowledge of administration and timing of re-vaccination 5: 48.3 4: 20.7 3: 13.8 2: 17.2 1: 0 Many pts were unaware/ confused about the need for post-CAR-T vaccinations