Objective: To investigate the efficacy and safety of low-dose Ruxolitinib in the treatment of patients with chronic graft-versus-host disease (cGVHD) and refractory to the first-line and/or second-line drugs after allogeneic hematopoietic stem cell transplantation. Methods: The clinical data was retrospectively analyzed of patients diagnosed with cGVHD in Anhui Provincial Hospital from July 9, 2018 to May 23, 2019. They were
refractory to first-line and second-line drugs and were given a low-dose of Ruxolitinib (a dose of 5 mg twice daily if body weight ≥ 25 kg and 2.5 mg twice daily if body weight<25 kg). There was 2.5 mg reduction per week or every two weeks if the condition improved until withdrawal. The efficacy and safety of Ruxolitinib were retrospectively analyzed weekly or biweekly. If the condition improved, the dosage would be reduced by 2.5 mg weekly or biweekly until discontinuance. Results: A total of 47 patients were included in the study,and the median time of taking Ruxolitinib was 55 (21-154) days. The median time of taking effect was 14(7-28) days. The overall response rate was 87.2% (41/47). The complete response rate was 63.8% (30/47) and the partial response rate was 23.4%(11/47). Among them, 13 cases were mild and the overall response rate was 100%(13/13). Twenty one cases were moderate and the overall response rate was 90.5%(19/21). Thirteen cases were severe and the overall response rate was 69.2%(9/13). The highest overall response rate of all organs the was 100% in the gastrointestinal tract (7/7), and it was 95.8%(23/24) for the skin, 83.3%(5/6) for the liver and 76.9%(10/13) for the lung. The highest rate of complete organ response was 95.8% for skin. Eight patients (17%) developed cytopenia, of which 2(4.2%) were with a decrease of 3-4 degree hemoglobin. Recrudescence of cytomegalovirus occurred in 3 patients (6.4%). After withdrawal of Ruxolitinib, 6 patients (12.7%) had recurrence of cGVHD. The median time to relapse was 35.5(7-90) days. All of their conditions were improved after addition of Ruxolitinib. The median time of response was 7(5-14) days. The median follow-up was 208(33-412) days. Three patients(6.4%) died, and all of them died of severe pulmonary infection. Three patients (6.4%) had relapse of primary disease. The 6-month overall survival rate was 95.7%. Conclusion: Low-dose Ruxolitinib has good efficacy and safety in the treatment of cGVHD.