Abstract Body (Do not enter title and authors here): Background: Immunosuppressive (IS) therapy is currently used as first-line treatment for heart transplant (HTx) rejection. However, they are not without complications, and less toxic therapies are needed. This study aims to compare extracorporeal photopheresis (ECP) as an adjuvant therapy with standard IS regimens in patients with HTx rejection.
Methods: This cross-sectional single-center study included HTx patients who underwent ECP in conjunction with standard IS therapy. Patient were matched with regular IS group in a 1:13 ratio based on rejection score. Data on graft function (International Society of Heart and Lung Transplantation (ISHLT) rejection score and left ventricular ejection fraction (LVEF)) at different time points and survival status were collected from the medical records.
Results: A total of 84 patients met the inclusion criteria (age at rejection diagnosis: 40.4±21.7 years, males: 58.4%). The median (range) of ECP duration in the ECP plus standard IS group was 228.5 (170-295) days. Patients in ECP adjuvant group had lower LVEF and similar rejection score distribution in comparison to the IS group (P= 0.047, and P= 0.707, respectively). However, matching in 1:1 ratio based additionally on age, sex, and race showed similar outcomes between groups (P> 0.05) (Table 1 & Figure 1). Kaplan-Meier analysis revealed similar survival benefits between groups (log-rank P: 0.12) (Figure 1E). The multivariate-adjusted odds ratio of graft status, LVEF improvement, all-cause and cardiovascular diseases mortality were not found to be different in the ECP adjuvant group compared to the standard IS group (P= 0.412, P= 0.449, P= 0.418, and P= 0.627 respectively) (Table 2).
Conclusions: ECP adjuvant therapy is non-inferior to standard IS regimen. Considering patients who do not respond well to IS therapy are referred for ECP, this treatment potentially improves their outcomes and reduces the risk of complications associated with heavy immunosuppression. Further studies are required to validate these findings.