Introduction: Hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHI) are currently attracting attention as a treatment for renal anemia. However, there are still few reports on the efficacy and safety of the administration to kidney transplant patients. This study aimed to investigate the effects and adverse events of administrating HIF-PHI to kidney transplant patients at our center.
Methods: A total of 42 kidney transplant patients were administrated HIF-PHI from January 2020 to June 2022, of whom 33 patients were included in this study. Five patients who reintroduced hemodialysis within one year after post-dose, three patients who discontinued administration for reasons other than adverse events, and one patient who was transferred to another hospital were excluded. We investigated patients' backgrounds, trends in data related to transplant kidney function, anemia, iron metabolism during the first year of administration, and the occurrence of adverse events. As a subanalysis, we compared clinical data with deep vein thrombosis onset (DVTO) and deep vein thrombosis non-onset　(DVTNO) groups.
Results: There was no significant difference in eGFR levels between pre-dose and 12 months post-dose. (28[20-30] vs 27[15-34] mL/min/1.73m2). Hb levels increased significantly from pre-dose to 12 months post-dose. (9.9[9-10] vs 11[10-12)] g/dl; p< 0.005).DVT was observed in 11 cases, 9 of whom were diagnosed with asymptomatic subclinical DVT by screening tests.Other adverse events included one case each of superficial vein thrombosis that developed after blood sampling and retinal vein occlusion.As a result of the subanalysis, the DVTO group was significantly older (56[45-67] vs 44[38-54]; p<0.05), and the dose of methylprednisolone was higher (4[4-4] vs 2[2-4] mg/day; p<0.05) compared with the DVTNO group. No significant differences were observed in Hb levels (10.9[9.8-11.8] vs 11.1[10.2-12.2] g/dl) and transferrin saturation levels (32[25-48] vs 29[22-39] %). In the DVTO group, total iron-binding capacity levels were significantly lower (293[268-321] vs 327[305-348] μg/dl; p<0.0001) and ferritin levels were significantly higher (214[148-283] vs 82(50-126) ng /ml; p <0.0001) compared with the DVTNO group. Although no significant difference was observed in diabetes incidence, HbA1c levels were significantly higher in the DVTO group than in the DVTNO group (5.9[5.5-6.4] vs 5.5[5.3-5.8] %; p<0.0001).
Conclusion: While a good improvement in posttransplant anemia was observed during the observation period, it included a relatively high number of thrombotic adverse events. Routine DVT screening tests were particularly required. In our data, Iron deficiency was not associated with DVT under HIF-PHI administration in kidney transplant recipients.