VPB0698 - Analysis of Low- and Intermediate-dose Prophylaxis of 30 Adult Patients with Severe Hemophilia A in a Single Center in Nanjing

Background: Limited data exist on the impact of prophylaxis (routine FVIII replacement) on adults with severe hemophilia A and pre-existing joint disease although prophylaxis has been recommended as the optimal therapy protocol for children.

Aims: To evaluate the clinical effects of low- and intermediate-dose factor VIII (FVIII) prophylaxis on adult patients with severe haemophilia A in a single HTC from Nanjing.

Methods: Data were retrospectively analyzed from 30 adults severe haemophilia A on regular low-dose (20 cases) or intermediate-dose (10 cases) prophylaxis. After a median follow-up of 48 months, the annual bleeding rate (ABR), annual joint bleeding rate (AJBR), the number of target joints, joint imaging scores (ultrasound HEAD-US score), Functional Independence Score in Hemophilia (FISH), quality of life score and health status score (SF-36) were compared between the two groups before and after prophylaxis.

Results: Compared with on-demand treatment before prophylaxis, low- and intermediate-dose prophylaxis significantly reduced ABR, AJBR and the number of target joints (P < 0.05), and the improvement of intermediate-dose prophylaxis group was better than that of low-dose prophylaxis group (P < 0.05). Compared with on-demand treatment, FISH score, quality of life score and SF-36 score were significantly improved (P < 0.05), but there was no significant difference between low-dose prophylaxis group and intermediate-dose prophylaxis group (P > 0.05). 11 patients received ultrasound HEAD-US score. 1 patient had significant improvement after right knee arthroplasty, 3 patients had no change in ultrasound score, and ultrasound score of the other 7 patients showed that the joint damage was still slowly aggravating after prophylaxis.

Conclusion(s): In adults with severe hemophilia A, low- and intermediate-dose prophylaxis can significantly reduce the bleeding frequency, delay the progress of joint lesions and improve the quality of life of patients as compared with on-demand treatment. The improvement of clinical bleeding in intermediate-dose prophylaxis was better than the low-dose prophylaxis.