emicizumab at a glance
Medicine class
Bispecific monoclonal antibody and systemic haemostatic agent
Main role
Prevention of bleeding in eligible people with haemophilia A
Administration
Injection under the skin after appropriate training
Important precaution
It alters several clotting-test results and can interact seriously with activated prothrombin complex concentrate
What is emicizumab used for?
It is licensed to prevent bleeding episodes in people of all ages with haemophilia A.
Haemophilia A with factor VIII inhibitors.
Severe haemophilia A without factor VIII inhibitors.
Moderate haemophilia A without inhibitors when there is a severe bleeding phenotype.
How does emicizumab work?
Emicizumab binds activated factor IX and factor X, bringing them together to replace the clot-promoting function normally provided by activated factor VIII. Factor VIII inhibitors do not neutralise it because its structure differs from factor VIII.
emicizumab preparations and strengths
Injection
Route: Parenteral
Strengths: 30 mg/mL, 150 mg/mL
How to take emicizumab
Use emicizumab exactly as instructed by the specialist haemophilia team. It is a ready-to-use, preservative-free solution injected under the skin.
A clinician or trained caregiver may give the injection; suitable patients can self-inject after training.
Use the abdomen, front of the thighs or upper outer arms, rotating sites.
Avoid red, bruised, tender, hard, scarred or mole-covered skin.
Do not shake, dilute or mix it with another medicine. Do not combine the two concentrations in one syringe.
Check that the solution is colourless to slightly yellow and free from visible particles.
Record the product name and batch number after each injection.
emicizumab side effects
Common or expected effects
- Injection-site redness, itching or pain
- Headache
- Joint pain
- Fever
- Muscle aches
- Diarrhoea
- Rash, itching or hives
Get urgent medical advice
- Symptoms of thrombotic microangiopathy, particularly when aPCC is also used
- Symptoms of a blood clot, including painful red swelling, visual disturbance or blackened skin
- Swelling of the face, tongue or throat, or difficulty swallowing or breathing
- Increasing breakthrough bleeding or reduced treatment effect
emicizumab in pregnancy
Clinical pregnancy data are unavailable. A specialist should assess the maternal benefit and possible fetal risk, including the increased background risk of thrombosis during and after pregnancy. Effective contraception is advised during treatment and for at least six months after stopping.
emicizumab while breastfeeding
It is uncertain whether emicizumab passes into human milk or affects milk production. The prescriber and patient should weigh the benefits of breastfeeding for the child and mother against continuing treatment.
emicizumab interactions
The haemophilia team must plan medicines used for breakthrough bleeding, surgery or dental procedures.
Activated prothrombin complex concentrate (aPCC)
Combined use can cause thrombotic microangiopathy or serious blood clots. It should be avoided unless the specialist team determines that no suitable alternative exists.
Recombinant activated factor VII or factor VIII
Emicizumab increases clotting potential, so use must be directed and monitored by the haemophilia team.
Systemic antifibrinolytics with aPCC or recombinant activated factor VII
Limited evidence means a possible increased risk of thrombosis should be considered.
Common questions about emicizumab
Answers are fully visible for fast scanning and source review.
Is emicizumab a factor VIII replacement?
No. It is an antibody that mimics a key function of activated factor VIII without having the same structure.
Does emicizumab treat an active bleed?
It is preventive treatment, not a stand-alone treatment for an active bleed. Follow the emergency bleeding plan from the haemophilia team.
Can emicizumab be injected at home?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.