Why my factor replacement therapy wasn’t working
As a woman with mild hemophilia A, I had difficulty getting answers
As a woman with hemophilia, one of the greatest challenges I face is being believed. This challenge is multifaceted.
First, I struggle to convince people that women can and do have hemophilia. Next, I have to explain that it’s possible for us to bleed like men with the condition do. I, too, will get large hematomas that take days to heal. When men with hemophilia say they’re bleeding, they typically aren’t questioned. I’ve often had to pull out photos of my bleeds to prove I’m not making them up. Thankfully, I have tons of pictorial evidence that quickly makes my case.
Additionally, I’ve had to prove the frequency of my bleeds. Some medical professionals and even fellow patients doubt I’d have a dozen or more bleeds a year, particularly when I’m on medication that should prevent and stop it. So what happens when I’m still bleeding? As a woman with hemophilia, I’m often doubted.
To be frank, it sucks.
Factor replacement therapy
People with hemophilia A, including myself, have lower levels of a protein called factor VIII (FVIII) that helps the blood form and hold clots. Lower factor levels can result in people bleeding longer when injured, as our bodies cannot stop the bleeding. Sometimes continued bleeding can cause serious complications, including death.
Thankfully, there are medications to help stop active bleeding. These are called factor replacement products, as they replace the factor we’re missing. Pharmacokinetic studies test these products’ half-life, which is how long it takes for half of the FVIII activity level to drop. The longer it stays active, the better it is at stopping bleeding. It’s an important test for people with hemophilia, but we don’t talk about it enough.
Things changed for me around 2016, when I realized the repercussions of living most of my life with undiagnosed hemophilia. I then learned to recognize bleeding symptoms and infuse FVIII to stop bleeds. I had FVIII at home to use when I needed it. When I took the medication, the bleeding seemed to slow down, but it didn’t stop. That made no sense, and I knew I needed answers.
Believe me when I say the FVIII isn’t working
“The factor you prescribed isn’t working to stop my bleeding. Will you please run a pharmacokinetic study to check the half-life of the factor in my body?” This request seemed simple, but it was far more complicated than I imagined.
When I told people I thought my factor wasn’t working, some said, “You don’t need to test the factor. If it’s not working, you’re not bleeding.” I knew I was bleeding. In fact, I bled for 30 days after my hysterectomy, needing 42 factor infusions to resolve bleeding that was soaking thick pads every 30 minutes.
Eventually I saw a hematologist who agreed to test the FVIII half-life, yet getting the answers I desperately needed still proved challenging. My blood was drawn at various times of day after I’d taken my meds. When my doctor entered the time points into a half-life calculator, it showed a near perfect half-life of 11.67 hours! (Twelve hours was the expected half-life for this medication.)
I was frustrated! My tests were completely normal, but my bleeding was anything but normal. That didn’t line up. As I stared at the numbers, I realized the calculations were wrong for me as a person with mild hemophilia.
Correcting miscalculations
Pharmacokinetic studies test how infused factor (factor that isn’t my own) is working. As a person with mild hemophilia, the inclusion of my own factor was skewing the calculations and falsely elevating my half-life. When we correctly entered only the numbers for the infused factor into the calculator, we discovered the half-life of the infused factor in my body was only 4.8 hours — not even close to the 12 it needed to be. The factor was not working!
Factor half-life calculations. (Courtesy of G Shellye Horowitz)
Through this experience, I learned two critical lessons. The first is the importance of isolating infused FVIII levels before calculating factor half-life in people with mild hemophilia. Understanding my actual half-life, my doctor switched me to a different FVIII replacement medication that stayed in my body longer and stopped my bleeds. I was so thankful! Finding the right FVIII therapy for my body greatly improved my quality of life.
Second, I learned I was right! That was a strong reminder to keep pushing for answers when I know a problem exists. It can be hard to self-advocate when tests appear normal, but we must find the strength to keep speaking up when we know something is wrong — until we get answers. We can’t let ourselves be silenced.
Note: Hemophilia News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The opinions expressed in this column are not those of Hemophilia News Today or its parent company, Bionews, and are intended to spark discussion about issues pertaining to hemophilia.
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