Individually Tailored Prophylaxis in Patients With Severe Hemophilia A
Status:
Terminated
Trial end date:
1969-12-31
Target enrollment:
Participant gender:
Summary
Patients with severe haemophilia A lack clotting factor FVIII and suffer from spontaneous and
traumatic bleeds. In the absence of treatment, frequent bleeds in joints lead to severe joint
destruction. In 1960s, prophylactic therapy was developed involving the infusion of clotting
factor on a regular schedule in order to keep clotting levels sufficiently high to prevent
spontaneous bleeding episodes. Prophylaxis is started at an early age before the age of 2
years or after the first joint bleed. The Malmö experience indicates that treatment is most
effective when administered in large doses at least 3 times weekly. However, such an
intensive treatment in young boys may be very difficult to carry out for home treatment.
Currently, there is no international recommendation on prophylactic therapy regimens. Because
of the high cost and limited availability of factor concentrates, dosing is an important
issue in prophylaxis therapy. It was recently shown that 24 hours after FVIII concentrate
administration, in patients presenting similar FVIIII levels, thrombin generation capacity
may be significantly different. In addition, independently of the FVIII level, a correlation
was found between severe clinical bleeding phenotype and thrombin generating capacity. The
aim of the present clinical study is to assess the thrombin generation test as the main
surrogate marker to evaluate the coagulating capacity of haemophiliacs on prophylaxis
regimen. Optimizing prophylactic therapy to patient's phenotype with no loss of clinical
effectiveness can significantly improve patients' quality of life, protect haemophilic
children against arthropathy and possibly limit the cost of the prophylaxis therapy.