Assessment of Cyclosporine Serum Concentrations on the Incidence of Acute Graft versus Host Disease Post Hematopoietic Stem Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment option for hematological disorders. Cyclosporine (CsA) is one of the major immunosuppressive agents for the prophylaxis against graft versus host disease (GvHD). In this retrospective study, we evaluated the effects of CsA serum levels on the incidence of acute GvHD and transplant outcomes. 103 adult patients received Hematopoitic Stem Cell Transplantation(HSCT) in the Hematology-Oncology, Bone Marrow Transplantation center at Shariati Hospital in Tehran, Iran. All participants received prophylactic regimen of cyclosporine plus methotrexate. CsA dose titration was done according to patients'' serum levels and drug toxicity. Serum levels tested on the twice weekly basis in first 4 weeks after transplantation.Acute GvHD (grades II-IV) developed in 44 patients (43%, 95%CI: 33%-52%). The median time to ANC and PLT recovery was 13 days (range: 9-31 days) and 16 days (range: 0-38 days), respectively. Univariate analysis of risk factors related to aGvHD (grade II-IV) development showed a higher risk of incidence of aGvHD (grades II-IV) for patients having the lowest blood CSA concentration (<200ng/ml) in the third weeks after transplantation (36% vs. 12%, P=0.035). The only risk factors related to incidence of aGvHD grades III-IV was also blood CsA concentration at 3rd week post transplant (15% vs. 3%, P=0.047). The CsA concentration at 3rd week was not related to disease free survival and overall survival (P=0.913 vs. P=0.81) respectively. Higher CsA serum levels in the third week post HSCT significantly decreased incidence of acute GvHD.