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PubMed This is a summary of 20 peer-reviewed journal articles Updated
Hematology

Standard of Care: Prophylaxis & Replacement Therapy

At a Glance

Prophylaxis is the standard of care for hemophilia, involving regular infusions of clotting factor to prevent bleeds before they start. Modern treatments use personalized approaches and extended half-life products to maintain protective factor levels and prevent long-term joint damage.

The primary goal of modern hemophilia care is simple: stop bleeds before they start. For decades, the focus was on treating bleeds after they occurred (called “on-demand” treatment). However, we now know that even one or two joint bleeds can lead to permanent damage. Today, the global standard of care is prophylaxis—the regular administration of clotting factor to maintain a steady level of protection in the blood [1][2][3].

Prophylaxis: Protecting Your Joints

When a bleed occurs in a joint, the iron in the blood acts like an acid, slowly eating away at the cartilage and bone. Even “silent” or subclinical bleeds—bleeds that don’t cause obvious swelling but cause a “funny feeling”—can lead to hemophilic arthropathy (chronic joint disease) over time [4][5]. Prophylaxis is superior to on-demand treatment because it keeps your factor levels above a certain “floor” (trough level), making it much harder for these bleeds to begin [6][7].

The Logistics of Infusions: Overcoming the Fear

For newly diagnosed patients or parents, the idea of finding a vein and administering intravenous (IV) medication multiple times a week can be terrifying. Rest assured, you will not have to figure this out alone.

  • Training: Your Hemophilia Treatment Center (HTC) will provide extensive, step-by-step training on how to self-infuse (or infuse your child) safely at home.
  • Ports for Children: For infants and young children whose veins are small and difficult to access, doctors often surgically place a port (port-a-cath) under the skin. This makes administering factor much easier and less painful during the early years.
  • Storage and Travel: Managing your supply becomes routine. While many factor products require refrigeration, most can be kept at room temperature for specific periods. Your HTC will teach you how to pack your factor for travel, ensuring you can still go on vacations and live a normal life.

Choosing the Right Factor: SHL vs. EHL

There are two main categories of replacement factors used in prophylaxis:

  • Standard Half-Life (SHL): These products have been the mainstay of treatment for years. However, they are processed by the body relatively quickly, often requiring infusions every other day or three times a week for Hemophilia A [8][9].
  • Extended Half-Life (EHL): These newer products are engineered to stay in your system longer. By extending the “half-life” (the time it takes for half of the factor to leave your body), EHL products often allow for fewer infusions (e.g., twice a week or even once a week for Hemophilia B) while maintaining higher levels of protection [10][11][12].

PK-Guided Prophylaxis: Personalized Medicine

Every person’s body processes medicine differently. Pharmacokinetics (PK) is the study of how your specific body absorbs, distributes, and clears the clotting factor [13].

  • The Old Way: Doctors used “weight-based dosing,” where everyone of the same weight got the same dose.
  • The Modern Way (PK-Guided): Your hematologist takes a few blood samples after an infusion to map your “PK curve.” This allows them to create a personalized schedule. If you are very active on Saturdays, they might time your infusion for Saturday morning to ensure you have the highest possible protection when you need it most [14][15][16].

The Importance of “Trough Levels”

The trough level is the lowest point your factor level reaches just before your next dose. In the past, the goal was to keep the trough above 1%. Today, many experts aim for higher troughs (3%, 5%, or even higher) to provide better protection for active patients or those with existing joint damage [17][18][19].

While replacement factor is the traditional cornerstone of care, other options like non-factor therapies and gene therapy are also available and may be discussed with your care team as part of your long-term plan [7][20].

Common questions in this guide

What is the difference between SHL and EHL clotting factors?
Standard Half-Life (SHL) products clear the body relatively quickly and may require infusions multiple times a week. Extended Half-Life (EHL) products are engineered to stay in your system longer, often allowing for fewer weekly infusions while maintaining strong protection against bleeds.
What does a target trough level mean in hemophilia treatment?
The trough level is the lowest point your clotting factor reaches right before your next dose. Doctors aim to keep this level high enough to protect against spontaneous and silent joint bleeds between your infusions.
What is PK-guided prophylaxis?
PK-guided prophylaxis is a highly personalized approach to your treatment schedule. Your hematologist measures how quickly your specific body absorbs and clears clotting factor, allowing them to tailor your infusion doses and timing for maximum protection when you are most active.
How do silent or subclinical bleeds affect hemophilia patients?
Subclinical or silent bleeds occur in the joints without obvious swelling but can cause a funny feeling or minor stiffness. Over time, these unnoticed bleeds can cause permanent damage to the cartilage and bone, leading to a chronic condition called hemophilic arthropathy.
Will my child need IV infusions for hemophilia treatment?
Yes, replacement factor is given intravenously. For infants and young children with small veins, doctors often surgically place a port under the skin. This makes administering the medication much easier and less painful during their early years.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.What is my/my child's target 'trough level,' and how does that number protect against silent, subclinical joint bleeds?
  2. 2.Would switching from a Standard Half-Life (SHL) to an Extended Half-Life (EHL) product help reduce the number of infusions we have to manage each week?
  3. 3.Can we perform a PK study (pharmacokinetic study) to see how my body specifically processes the factor, rather than just using a weight-based dose?
  4. 4.If we see signs of joint damage on a Hemophilia Joint Health Score (HJHS) assessment, should we consider a more aggressive prophylaxis schedule?
  5. 5.How do we balance physical activity levels with our prophylaxis schedule to ensure the most protection during high-impact times?

Questions For You

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References

References (20)
  1. 1

    A milder clinical course for severe hemophilia B: a true or biased effect?

    van Miert JH, Hop H, Borjas-Howard JF, Meijer K

    Haematologica 2016; (101(6)):e266 doi:10.3324/haematol.2016.147298.

    PMID: 27252514
  2. 2

    Emicizumab Prophylaxis in Patients Who Have Hemophilia A without Inhibitors.

    Mahlangu J, Oldenburg J, Paz-Priel I, et al.

    The New England journal of medicine 2018; (379(9)):811-822 doi:10.1056/NEJMoa1803550.

    PMID: 30157389
  3. 3

    Aspects of prophylactic treatment of hemophilia.

    Ljung R

    Thrombosis journal 2016; (14(Suppl 1)):30 doi:10.1186/s12959-016-0103-3.

    PMID: 27766056
  4. 4

    Hemophilic arthropathy: Current knowledge and future perspectives.

    Gualtierotti R, Solimeno LP, Peyvandi F

    Journal of thrombosis and haemostasis : JTH 2021; (19(9)):2112-2121 doi:10.1111/jth.15444.

    PMID: 34197690
  5. 5

    Hemophilic arthropathy: how to diagnose subclinical bleeding early and how to orthopedically treat a damaged joint.

    Rodriguez-Merchan EC

    Expert review of hematology 2023; (16(9)):651-658 doi:10.1080/17474086.2023.2232547.

    PMID: 37392151
  6. 6

    From a bispecific monoclonal antibody to gene therapy: A new era in the treatment of hemophilia A.

    Mihaila RG

    Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia 2023; (167(1)):1-8 doi:10.5507/bp.2022.046.

    PMID: 36413008
  7. 7

    Nothing short of a revolution: Novel extended half-life factor VIII replacement products and non-replacement agents reshape the treatment landscape in hemophilia A.

    Abdelgawad HAH, Foster R, Otto M

    Blood reviews 2024; (64()):101164 doi:10.1016/j.blre.2023.101164.

    PMID: 38216442
  8. 8

    Measuring the impact of changing from standard half-life (SHL) to extended half-life (EHL) FVIII prophylaxis on health-related quality of life (HRQoL) in boys with moderate/severe haemophilia A: Lessons learned with the CHO-KLAT tool.

    Carcao M, Zunino L, Young NL, et al.

    Haemophilia : the official journal of the World Federation of Hemophilia 2020; (26(1)):73-78 doi:10.1111/hae.13905.

    PMID: 31865620
  9. 9

    Extended Half-Life Factor VIII and Factor IX Preparations.

    Graf L

    Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft fur Transfusionsmedizin und Immunhamatologie 2018; (45(2)):86-91 doi:10.1159/000488060.

    PMID: 29765290
  10. 10

    BIVV001 Fusion Protein as Factor VIII Replacement Therapy for Hemophilia A.

    Konkle BA, Shapiro AD, Quon DV, et al.

    The New England journal of medicine 2020; (383(11)):1018-1027 doi:10.1056/NEJMoa2002699.

    PMID: 32905674
  11. 11

    [Translated article] Pharmacokinetic-guided switching from standard half-life factor VIII to extended half-life pegylated factor VIII in haemophilia A therapy in clinical practice.

    Choví-Trull M, Megías-Vericat JE, Bonanad Boix S, et al.

    Farmacia hospitalaria : organo oficial de expresion cientifica de la Sociedad Espanola de Farmacia Hospitalaria 2025; (49(4)):T205-T211 doi:10.1016/j.farma.2024.12.007.

    PMID: 39952826
  12. 12

    Decreased Bleeding Rates in Patients with Hemophilia A Switching from Standard-Half-Life FVIII to BAY 94-9027 Prophylaxis.

    Mancuso ME, Reding MT, Negrier C, et al.

    Thrombosis and haemostasis 2021; (121(8)):1079-1086 doi:10.1055/a-1333-5536.

    PMID: 33296943
  13. 13

    Setting the stage for individualized therapy in hemophilia: What role can pharmacokinetics play?

    Hazendonk HCAM, van Moort I, Mathôt RAA, et al.

    Blood reviews 2018; (32(4)):265-271 doi:10.1016/j.blre.2018.01.001.

    PMID: 29426727
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    The Impact of Pharmacokinetic-Guided Prophylaxis on Clinical Outcomes and Healthcare Resource Utilization in Hemophilia A Patients: Real-World Evidence from the CHESS II Study.

    Ferri Grazzi E, Sun SX, Burke T, O'Hara J

    Journal of blood medicine 2022; (13()):505-516 doi:10.2147/JBM.S363028.

    PMID: 36157322
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    Pharmacokinetics in routine haemophilia clinical practice: rationale and modalities-a practical review.

    Hermans C, Dolan G

    Therapeutic advances in hematology 2020; (11()):2040620720966888 doi:10.1177/2040620720966888.

    PMID: 33194165
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    Pharmacokinetics of perioperative FVIII in adult patients with haemophilia A: An external validation and development of an alternative population pharmacokinetic model.

    Zhu J, Wu YS, Beechinor RJ, et al.

    Haemophilia : the official journal of the World Federation of Hemophilia 2021; (27(6)):974-983 doi:10.1111/hae.14393.

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    Quantifying the optimal factor VIII levels to achieve patient-centric and clinician-relevant outcomes among people with hemophilia A: a SHELF elicitation study.

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    PMID: 41185547
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    Moderate- to vigorous-intensity physical activities for hemophilia A patients during low-dose pharmacokinetic-guided extended half-life factor VIII prophylaxis.

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  19. 19

    Blood-Induced Arthropathy: A Major Disabling Complication of Haemophilia.

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  20. 20

    Gene Therapy with Fidanacogene Elaparvovec in Adults with Hemophilia B.

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    PMID: 39321362

This page provides educational information on hemophilia prophylaxis and factor replacement. Always consult your hematologist or Hemophilia Treatment Center to determine the best treatment schedule and factor product for you or your child.

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