Survey findings of clinical outcomes and provider attitudes about prophylactic (preventive) treatment in adults with hemophilia A in the U.S. were published in the September issue of the journal Haemophilia. While “primary prophylaxis” denotes long-term, continuous treatment started either before the age of two or after the initial joint bleed, “secondary prophylaxis” refers to treatment that is given for a finite period, usually in response to repeated bleeding (often into a joint) that has not been managed effectively with demand therapy.
The survey was developed by the “ad hoc” Adult Prophylaxis Study Group (APSG), a group of hematologists from several hemophilia treatment centers (HTCs). The article was co-authored by Christopher E. Walsh, MD, PhD, Department of Medicine, Tisch Cancer Center, Mount Sinai School of Medicine in New York City and Leonard A. Valentino, MD, Departments of Pediatrics and Internal Medicine, Rush University Medical Center in Chicago, IL.
APSG considers the survey a step toward providing evidence-based guidelines for adult prophylaxis. While prior study and clinical practice have demonstrated the value of prophylaxis in children, similar studies and practice in adults are relatively new. Though the data collected by the APSG represent a relatively small group of patients, investigators anticipate it will lead to future trials comparing prophylaxis with on-demand regimens in adults.
The APSG survey was sent to 23 HTCs, with 10 responding. The patients represented comprise 145 adults from 18-72 years, with a mean age of 34 years old. Of those, 48 (33%) were on prophylaxis when first seen at the HTC, while 97 (67%) were not. The prophylactic regimen was modified for 22 of the 48, or 46%, often because of breakthrough bleeding. Five of 21 patients (24%) for whom data were available discontinued prophylaxis; three of the five, or 60%, experienced increased bleeding episodes and the other two (40%) subsequently resumed regular prophylactic infusions because of the increased bleeding.
Of the 77 patients not initially receiving prophylaxis for whom data were available, prophylaxis was started or resumed in all. It was modified in 57, or 74%, of them at some point during treatment, typically because of breakthrough bleeding.
The surveys also included the attitudes of treatment providers. Results indicated that there was consensus that prophylaxis is suitable in certain adults with severe hemophilia. The authors divided adult patients warranting prophylaxis into three categories: (1) patients who have been on primary prophylaxis (regular, long-term infusion of factor started before two years of age and/or after no more than one joint bleed) since childhood and have little or no joint damage; (2) patients who have never received prophylaxis and experience limb- or life-threatening bleeding; and (3) those who have never received prophylaxis and experience frequent joint bleeds.
The authors reported that the most “compelling” reasons for resuming prophylaxis in adults who discontinued treatment at some point are life- or limb-threatening bleeding and 5–8 significant joint or soft tissue bleeds in a one-month period. The most significant barriers to the use of prophylaxis in adults were poor adherence and the high cost.
“Initiating, restarting or continuing prophylaxis in adults with severe haemophilia A may provide some of the same benefits experienced by paediatric patients on prophylaxis,” wrote the authors.
“Although the survey data concerned a relatively small number of subjects, the findings indicate that secondary prophylaxis is being used in adults with haemophilia A and that those on prophylactic regimens appear to bleed less frequently. The results are encouraging and suggest that it may be possible to slow the progression of joint disease and improve QOL (quality of life) in older haemophilia patients.”
The article, “Factor VIII Prophylaxis for Adult Patients with Severe Haemophilia A: Results of a US Survey of Attitudes and Practices,” was published in the September 2009 issue of Haemophilia.