367: Survival after Extracorporeal Photopheresis (ECP) for Treatment of Graft-Versus-Host Disease (GVHD) is Predicted by GVHD Classification as Proposed by National Institute of Health (NIH) Consensus Criteria

ECP is used in GVHD treatment with variable response. The clinical phenotype of GVHD associated with ECP responsiveness is not clear. Subtypes of GVHD proposed by NIH consensus criteria affect survival after allogeneic stem cell transplant (SCT) (BBMT 2007 Oct; 13(10):1207–15). We hypothesized that survival after ECP will be determined by NIH subtypes of GVHD. Methods: Review of patients undergoing ECP for GVHD treatment was done. 55 patients (pts.) were identified and GVHD was reclassified using NIH criteria. Pts. with acute GVHD (aGVHD) were graded using Glucksberg criteria. Pts. with overlap or classic chronic GVHD (cGVHD) were scored using NIH criteria. Overall survival (OS) was measured from starting ECP. ECP indication was steroid dependency or refractoriness. Results: Classic aGVHD (26%), recurrent aGVHD (7%), overlap cGVHD (16%) and classic cGVHD (51%) accounted for the subtypes. Pts. started ECP at a median of 216 days after SCT (range, 41 to 2946). The median number of GVHD recurrences prior to ECP start was 2 (range, 0–6). Pts. with classic cGVHD started ECP significantly later (145 days vs. 53 days, P < 0.001), continued it for a longer time (245 vs. 104, P = 0.004) and received more treatments (13 vs. 8, P = 0.006), compared with non-classic cGVHD. The steroid dose (mg/kg) prior to ECP was lower in classic cGVHD (0.43 vs. 1.21, P < 0.001). 25 of 38 pts. (66%) with classic cGVHD were on ≤1 mg/kg of prednisone at ECP start, and 14/17 (82%) of pts. with non-classic cGVHD were on > 1 mg/kg of steroids (P = 0.001). For the entire cohort, the steroid dose at month 2 of ECP was significantly less (0.81 vs. 0.38, P = 0.004). In pts. with classic cGVHD, there was a trend in decrease in skin subscale scores after 2 months of ECP. In univariate analysis, OS was superior for classic cGVHD compared with other subtypes (median survival not reached vs. 78 days, P < 0.001; 1-yr OS 65% vs. 10%). OS was better for pts. with steroid dose ≤ 1 mg/kg at start of ECP compared with pts. on higher dose steroid (median survival not reached vs. 69 days, P < 0.001, 1-yr OS 65% vs. 0%). Using Cox regression (adjusted for steroid dose) non-classic cGVHD was an independent prognostic feature for poor survival (HR 4.72, 95% CI 1.84–12.41, P = 0.001). Conclusion: Pts. with classic cGVHD had a superior survival after ECP compared to other NIH subtypes. Survival after ECP with other GVHD subtypes is poor and combination of novel steroid sparing agents with ECP need to be explored.