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emicizumab

First FDA approval 11/16/2017: 9 years on the US market.

This grade answers one narrow question: how strong is the public evidence and safety record behind this drug, and how clean is its money trail and court record? It is not a verdict on whether the drug is right for you.

C

Score breakdown (66/100)

Safety ×35%
C
Evidence ×25%
F
Regulatory ×15%
A
Money & lawsuits ×15%
A
Options ×10%
F

Safety: 65

Evidence: 36

Regulatory history: 100

Money & lawsuits: 100

Options: 40

FDA boxed warning

WARNING: THROMBOTIC MICROANGIOPATHY AND THROMBOEMBOLISM Cases of thrombotic microangiopathy and thrombotic events were reported when on average a cumulative amount of >100 U/kg/24 hours of activated prothrombin complex concentrate was administered for 24 hours or more to patients receiving HEMLIBRA prophylaxis. Monitor for the development of thrombotic microangiopathy and thrombotic events if aPCC is administered. Discontinue aPCC and suspend dosing of HEMLIBRA if symptoms occur. WARNING: THROMBOTIC MICROANGIOPATHY and THROMBOEMBOLISM See full prescribing information for complete boxed warning. Cases of thrombotic microangiopathy and thrombotic events were reported when on average a cumulative amount of >100 U/kg/24 hours of activated prothrombin complex concentrate (aPCC) was administered for 24 hours or more to patients receiving HEMLIBRA prophylaxis. Monitor for the development of thrombotic microangiopathy and thrombotic events if aPCC is administered. Discontinue aPCC and suspend dosing of HEMLIBRA if symptoms occur.

Independent reviews and post-approval warnings

WHO Essential Medicine

Listed on the WHO Model List of Essential Medicines: a global expert panel judged it among the medicines a health system should always have, on evidence of value, not marketing.

What the FDA label says

Approved uses

is indicated for routine prophylaxis to prevent or reduce the frequency of bleeding episodes in adult and pediatric patients ages newborn and older with hemophilia A (congenital factor VIII deficiency) with or without factor VIII inhibitors. HEMLIBRA is a bispecific factor IXa- and factor X-directed antibody indicated for routine prophylaxis to prevent or reduce the frequency of bleeding episodes in adult and pediatric patients ages newborn and older with hemophilia A (congenital factor VIII deficiency) with or without factor VIII inhibitors. ( 1 )

Contraindications

None. None ( 4 )

Warnings and precautions

Immunogenicity: Anti-emicizumab antibodies (including neutralizing antibodies) have developed in HEMLIBRA-treated patients. In case of clinical signs of loss of efficacy, promptly assess the etiology and consider a change in treatment if neutralizing antibodies are suspected. ( 5.3 , 12.6 , 14.3 ) Laboratory Coagulation Test Interference: HEMLIBRA interferes with activated clotting time (ACT), activated partial thromboplastin time (aPTT), and coagulation laboratory tests based on aPTT, including one-stage aPTT-based single-factor assays, aPTT-based Activated Protein C Resistance (APC-R), and Bethesda assays (clotting-based) for factor VIII (FVIII) inhibitor titers. Intrinsic pathway clotting-based laboratory tests should not be used. ( 5.4 , 7.2 ) 5.1 Thrombotic Microangiopathy Associated with HEMLIBRA and aPCC Cases of thrombotic microangiopathy (TMA) were reported from clinical trials when on average a cumulative amount of >100 U/kg/24 hours of activated prothrombin complex concentrate (aPCC) was administered for 24 hours or more to patients receiving HEMLIBRA prophylaxis. In clinical trials, thrombotic microangiopathy was reported in 0.8% of patients (3/391) and in 8.1% of patie...

Adverse reactions (label)

The following serious adverse reactions are described elsewhere in the labeling: Thrombotic Microangiopathy Associated with HEMLIBRA and aPCC [see Warnings and Precautions (5.1) ] Thromboembolism Associated with HEMLIBRA and aPCC [see Warnings and Precautions (5.2) ] Most common adverse reactions (incidence ≥ 10%) are injection site reactions, headache, and arthralgia. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Genentech at 1-888-835-2555 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The following adverse reactions are based on pooled data from two randomized trials in adult and adolescent patients (HAVEN 1 and HAVEN 3), one single-arm trial in adult and adolescent patients (HAVEN 4), one single-arm trial in pediatric patients (HAVEN 2), and one dose-finding trial, in which a total of 391 male patients with hemophilia A received at least one dose of HEMLIBRA as routine prophyl...

Source: FDA SPL label for Hemlibra (Genentech, Inc.), effective 20250711. Full label on DailyMed.

Side-effect reports sent to the FDA

These are counts of reports people filed, not rates of harm. Anyone can file one, and nobody checks whether the drug was the cause. Millions of doses are taken for every report sent, so the useful part is how this drug compares with the average across all drugs.

1,018reports that mention this drug
1,016of those blame this drug, not another one the person was taking
72%of reports describe a serious outcome, such as a hospital stay (average for all drugs: 57%)
5.6%of reports include a death, from any cause (average for all drugs: 9.1%)

Problems reported most often

Off Label Use · 158Haemarthrosis · 132Haemorrhage · 110No Adverse Event · 84Drug Ineffective · 67Haematoma · 42Fall · 32Muscle Haemorrhage · 30Arthralgia · 28Headache · 24Anti Factor Viii Antibody Positive · 23Head Injury · 22Pyrexia · 21Drug Specific Antibody Present · 20Haematuria · 20

Reports per year

20192020202120222023202420252026
3262958711332517899

Source: the FDA's Adverse Event Reporting System (FAERS). Reports are voluntary and unverified. Drugs that are prescribed a lot, in the news, or in lawsuits attract more reports, so the percentages are compared with the whole database to correct for that partly, not fully.

Recalls and regulatory record

0recall actions on file
0 / 0brand / generic applications
0label changes since 2021
NoREMS program

Evidence base

7randomized trials (PubMed)
11systematic reviews
57registered trials
88%of completed trials posted results
14%terminated or withdrawn
70%industry-funded

Counts measure how much evidence exists and how transparent it is, not how big the benefit is. For that, ask your prescriber: if 100 people like me took this, how many would get better because of it, and how many would be harmed? (Doctors call these the "number needed to treat" and "number needed to harm.") It differs by condition and is the number drug ads leave out. Sources: PubMed, ClinicalTrials.gov.

Money and lawsuits

In 2024, drug companies reported $0 in payments to US physicians and hospitals tied to this drug across 0 transactions.

No pending federal MDL names this drug or its brands.

Not named in any federal pharmaceutical settlement of $100M or more on record.

Sources: CMS Open Payments (Sunshine Act); Judicial Panel on Multidistrict Litigation pending docket list; DOJ settlements as tabulated on Wikipedia with links to the primary record. State-court and individual suits are not included.

Who takes it and what it costs

Not in the Medicare Part D spending file (typically hospital-administered or very new drugs).

Same-class alternatives

No same-class alternatives found in RxClass.

Questions to ask your prescriber

  1. This drug carries a boxed warning. Which specific risk does it cover, and does it apply to me?
  2. The most-reported problems in FDA's adverse event data are haemarthrosis, haemorrhage, no adverse event. How would we recognize and handle those?
  3. Off-label use is among the most-reported items for this drug. Is my use on-label, and if not, what evidence supports it?
  4. There is no generic. Is there an older generic in the same class that works as well for my situation?
  5. What result are we expecting, by when, and what is the plan if it does not happen?
  6. If 100 people like me took this drug, how many would actually get better because of it, and how many would be harmed by it? (Doctors call these the number needed to treat and the number needed to harm.)