Emicizumab
Emicizumab is a bispecific antibody used as routine prophylaxis to prevent or reduce bleeding episodes in adults and children with hemophilia A (congenital factor VIII deficiency), with or without factor VIII inhibitors.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert ▾
Important safety warning: Hemlibra combined with high doses of a clotting product called aPCC (activated prothrombin complex concentrate) can cause life-threatening blood clotting problems. Two serious conditions have been reported: thrombotic microangiopathy (TMA) — a condition where tiny blood vessels are damaged, harming the kidneys and breaking down red blood cells — and thromboembolism (dangerous blood clots in vessels). These problems occurred when large cumulative amounts of aPCC were given for 24 hours or more to people already taking Hemlibra. Watch for warning signs such as unusual bruising, decreased urination, extreme fatigue, confusion, chest pain, or leg swelling. If these symptoms appear, aPCC must be stopped immediately and Hemlibra paused. Anyone managing a bleeding emergency in a Hemlibra patient should know about this risk before reaching for aPCC.
📖 Emicizumab: Patient Information Guide
A plain-language walkthrough of Emicizumab — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.
🎯What it's used for▾
Emicizumab is approved for one main purpose: routine prophylaxis in people with hemophilia A.
- Hemlibra (subcutaneous injection) is indicated for routine prophylaxis to prevent or reduce the frequency of bleeding episodes in adult and pediatric patients, from newborns and older, with hemophilia A (congenital factor VIII deficiency) — both with and without factor VIII inhibitors (antibodies that make standard clotting factor treatments ineffective).
⚙️How it works▾
In hemophilia A, the body is missing or has a deficient amount of clotting factor VIII — a protein that normally acts as a helper molecule linking two other clotting proteins, factor IXa and factor X, to form effective blood clots. Emicizumab is a bispecific antibody, meaning it is engineered to grab onto two different targets at the same time. It bridges activated factor IXa and factor X in the same way that missing activated factor VIII would — restoring the clotting process and helping the blood stop bleeding more effectively.
Importantly, emicizumab does not require activation by thrombin the way natural factor VIII does, which also means it remains active even when factor VIII inhibitors are present — one reason it is effective in patients for whom traditional replacement therapy has stopped working.
💊How it's taken▾
Hemlibra is given as a subcutaneous injection (under the skin) and is for subcutaneous use only. It is started with a loading-dose phase given once weekly for the first 4 weeks to quickly build up effective levels in the body, then continued at a maintenance dose chosen by the healthcare provider. Maintenance options include once weekly, once every two weeks, or once every four weeks — the schedule is tailored to the patient's needs and to promote adherence.
- Injections can be given in the abdomen, thigh, or upper outer arm (upper arm by a caregiver or healthcare provider only).
- Rotate the injection site with each dose; never inject into irritated, bruised, or scarred skin.
- If you miss a dose, give it as soon as you remember and then return to your regular schedule — never give two doses on the same day to make up for a missed one.
- Self-injection is not recommended for children under 7 years of age; a caregiver or healthcare provider should administer it for younger children.
🤒Side effects — in detail▾
The most common side effects with Hemlibra involve the injection site and general symptoms:
- Injection site reactions — redness, pain, itching, swelling, bruising, or warmth at the injection spot (reported in about 1 in 5 patients; most are mild to moderate and resolve on their own)
- Headache
- Joint pain (arthralgia)
- Fever (pyrexia)
- Diarrhea
Serious but less common reactions include thrombotic microangiopathy (TMA — dangerous damage to small blood vessels) and blood clots (thromboembolism), particularly when the clotting product aPCC is used at the same time. These require immediate medical attention. Also watch for signs that Hemlibra may be losing effectiveness, such as more frequent or harder-to-control bleeding episodes.
⚠️Warnings & precautions▾
- aPCC interaction and clotting risk (boxed warning): Combining Hemlibra with high cumulative doses of aPCC (a clotting product) for 24 hours or more can cause TMA (small vessel damage with kidney injury and red blood cell breakdown) and serious blood clots. If you need aPCC urgently, the dose should be kept as low as possible and your care team must monitor closely. Stop aPCC and pause Hemlibra immediately if symptoms develop. This risk can last up to 6 months after stopping Hemlibra due to its long half-life.
- Antibody development (immunogenicity): A small number of patients develop anti-drug antibodies that can reduce Hemlibra's effectiveness. Tell your doctor if your bleeding becomes harder to control — this may be a sign of neutralizing antibodies.
- Lab test interference: Hemlibra interferes with a wide range of standard blood clotting tests (aPTT-based tests, ACT). Results will appear falsely shortened and must not be used to guide dosing of clotting factors or anticoagulants. Always inform every lab and healthcare provider that you are taking Hemlibra so they use the correct tests (chromogenic or immuno-based assays are unaffected).
🔀What it interacts with▾
There are two key interaction concerns with Hemlibra:
- aPCC (activated prothrombin complex concentrate, e.g., FEIBA): This is the most dangerous interaction. High doses of aPCC used alongside Hemlibra can cause life-threatening blood clotting complications — thrombotic microangiopathy and thromboembolism. Use only when absolutely necessary, at the lowest effective dose, with close medical monitoring.
- aPTT-based laboratory tests: Hemlibra interferes with activated partial thromboplastin time (aPTT) tests and all tests that rely on them — including one-stage factor VIII assays and certain inhibitor-titer tests. These should not be used to monitor coagulation in patients on Hemlibra. Chromogenic tests using bovine proteins and immuno-based assays are not affected and can be used instead. This effect on lab tests can persist up to 6 months after the last Hemlibra dose.
This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.
📋Before taking it▾
- Pregnancy: Safety of Hemlibra during pregnancy has not been established. Women who can become pregnant should use effective contraception while taking it. Use during pregnancy only if the benefit to the mother clearly outweighs potential risk to the fetus.
- Breastfeeding: It is not known whether emicizumab passes into breast milk. Discuss the risks and benefits with your doctor before breastfeeding while on Hemlibra.
- Children: Hemlibra has been studied and is approved for pediatric patients from newborns and older. Drug levels may be somewhat lower in infants under 6 months old. Self-injection is not recommended for children under 7 years — a caregiver or healthcare provider should administer injections in young children.
- Older adults (65+): Clinical trials included limited numbers of patients 65 and older, so differences in response compared to younger adults cannot be ruled out. Discuss your overall health history with your prescriber.
- Liver or kidney impairment: Hemlibra's pharmacokinetics are not meaningfully changed by mild or moderate liver or kidney impairment. However, it has not been studied in patients with severe liver or kidney disease — inform your doctor if this applies to you.
- Anti-drug antibodies: In rare cases, the body can develop antibodies against Hemlibra that reduce its effectiveness. Report any increase in breakthrough bleeding to your doctor promptly.
🔬Pharmacokinetics — how your body processes it▾
After a subcutaneous injection, emicizumab is absorbed relatively slowly, with an absorption half-life of about 1.6 days, and reaches high bioavailability (roughly 80–93% of the dose enters the bloodstream). The drug distributes into a small volume — mostly staying in the bloodstream and nearby tissues — and is cleared slowly, with an elimination half-life of about 27 days. This long half-life is why steady, protective drug levels can be maintained with weekly, every-two-week, or every-four-week dosing.
Dosing is weight-based (per kilogram of body weight), which keeps drug exposure similar across a wide range of body sizes. Drug levels are not meaningfully affected by age (in patients over 1 year), race, inhibitor status, or mild-to-moderate liver or kidney impairment. Because of this long half-life, Hemlibra's effects on coagulation lab tests and its potential interaction with aPCC can persist for up to 6 months after the last dose.
📦How to store it▾
Store HEMLIBRA vials in a refrigerator at 2°C to 8°C (36°F to 46°F) in the original carton to protect from light. Do not freeze. stored out of and then returned to refrigeration.
📄 Written from Emicizumab’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →
🩺 Pharmacist Counseling Corner
Quick, plain-English answers to the questions patients ask most about Emicizumab — the kind of thing our pharmacy team would talk through with you at the counter.
What exactly does Hemlibra do — is it the same as taking factor VIII? ▾
How often do I need to inject myself, and can I do it at home? ▾
What side effects should I expect, and what should prompt me to call someone? ▾
I've heard I can't take a certain clotting product with Hemlibra — what's that about? ▾
Will Hemlibra affect my blood test results? ▾
Is it safe to take Hemlibra if I'm pregnant or trying to conceive? ▾
Is Emicizumab available over the counter? ▾
When was Emicizumab first available? ▾
Who makes Emicizumab? ▾
💬 Answers drafted from Emicizumab’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →
🧰 Keep exploring
💊 How Emicizumab comes
Emicizumab is available in 2 forms. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Injection
How this form is used
- Hemlibra is used as routine prophylaxis to prevent or reduce bleeding episodes in adults and children (from newborns and older) with hemophilia A, with or without factor VIII inhibitors
- Hemlibra is given as a subcutaneous (under-the-skin) injection only — never by any other route
- Hemlibra is started with a loading-dose schedule for the first 4 weeks, followed by a maintenance schedule (weekly, every 2 weeks, or every 4 weeks) as directed by your healthcare provider
- Hemlibra injections should be rotated among sites — upper outer arm (caregiver/HCP only), thigh, or abdomen — and never given into moles, scars, or broken or irritated skin
- If a Hemlibra dose is missed, take it as soon as you remember and then resume your usual schedule — never double up with two doses on the same day
Oral solution
📊 Emicizumab across the U.S. market
How Emicizumab appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
FDA-listed product records by dose form (tablet variants merged) — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
📈 How widely Emicizumab is used
A general measure of how commonly Emicizumab is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Emicizumab is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Emicizumab prescribed? Of the 1,596 medications we measure, Emicizumab ranks #755 by Medicaid prescriptions — more than 53% of them.
Utilization by Emicizumab product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
0.4 ML emicizumab-kxwh 150 MG/ML Injection Most dispensed
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 1989814
0.7 ML emicizumab-kxwh 150 MG/ML Injection
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 1989809
1 ML emicizumab-kxwh 150 MG/ML Injection
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 1989816
2 ML emicizumab-kxwh 150 MG/ML Injection
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 2632728
1 ML emicizumab-kxwh 30 MG/ML Injection
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 1989799
0.4 ML emicizumab-kxwh 30 MG/ML Injection
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 2675567
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Emicizumab, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 6 of 6 listed Emicizumab NDCs with Medicaid activity.
🔍 Compare Emicizumab products
A representative set of FDA-listed product records for Emicizumab — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Injection | ||||
| 30 mg/mL | — | Chugai Pharmaceutical Co., Ltd. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 60 mg/0.4 mL | — | Chugai Pharmaceutical Co., Ltd. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 105 mg/0.7 mL | — | Chugai Pharmaceutical Co., Ltd. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 150 mg/mL | — | Chugai Pharmaceutical Co., Ltd. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 12 mg/0.4 mL | Subcutaneous | Genentech, Inc. | BLA | View NDC → |
| 30 mg/mL | Subcutaneous | Genentech, Inc. × 3 listings | BLA | View NDC → |
| 60 mg/0.4 mL | Subcutaneous | Genentech, Inc. × 2 listings | BLA | View NDC → |
| 105 mg/0.7 mL | Subcutaneous | Genentech, Inc. × 2 listings | BLA | View NDC → |
| 150 mg/mL | Subcutaneous | Genentech, Inc. × 5 listings | BLA | View NDC → |
| 300 mg/2 mL | Subcutaneous | Genentech, Inc. × 2 listings | BLA | View NDC → |
| 12 mg/0.4 mL | — | Samsung BioLogics Co. LTD | DRUG FOR FURTHER PROCESSING | View NDC → |
| 300 mg/2 mL | — | Samsung BioLogics Co. LTD | DRUG FOR FURTHER PROCESSING | View NDC → |
| 💊Oral solution | ||||
| 150 mg/0.001 L | — | Chugai Pharmaceutical Co., Ltd. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 30 mg | — | SAMSUNG BIOLOGICS Co., Ltd. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 60 mg | — | SAMSUNG BIOLOGICS Co., Ltd. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 105 mg | — | SAMSUNG BIOLOGICS Co., Ltd. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 150 mg | — | SAMSUNG BIOLOGICS Co., Ltd. | DRUG FOR FURTHER PROCESSING | View NDC → |
Showing 26 of 26 products — FDA National Drug Code Directory. See every product, package size and price: browse all 26 Emicizumab NDCs →
📈 What people report — real-world data (FDA FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Emicizumab — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Emicizumab in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
🏛️ The road to your pharmacy
How Emicizumab went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
🚨 Recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
Source: openFDA drug enforcement (recall) reports.
RxNorm Concept Web — From Ingredient to Every Form and Strength
This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.
RxCUI 1989794 1 dose form · 6 strengths
-
Dose form (SCDF) Injection RxCUI 1989798In current FDA listingsClinical drug / strength (SCD) 0.4 ML emicizumab-kxwh 150 MG/MLRxCUI 19898140.4 ML emicizumab-kxwh 30 MG/MLRxCUI 26755670.7 ML emicizumab-kxwh 150 MG/MLRxCUI 19898091 ML emicizumab-kxwh 150 MG/MLRxCUI 19898161 ML emicizumab-kxwh 30 MG/MLRxCUI 19897992 ML emicizumab-kxwh 150 MG/MLRxCUI 2632728
Look up RxCUI 1989794 in the RxCUI Atlas →
RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.
📦 Supply & shortage status
Whether Emicizumab is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
🏷️ Sold under these brand names
🏭 Manufacturers & labelers
RxNorm drug class
Emicizumab belongs to the Other systemic hemostatics class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
🔬 Where this comes from
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How we combine label and product data
HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 1 FDA-filed SPL label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.
For canonical ingredient pages, bounded product-attributed indication and administration excerpts may be added to the AI evidence, and the generator is instructed to preserve available product, brand, route, and form qualifiers instead of treating one label as universal. Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Genentech, Inc. is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.
This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.